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Fumigant Toxicity of some Essential Oils on Adults of some Stored-Product Pests
Provedor de dados: 117
Autores: Mahmoudvand,Mohammad; Abbasipour,Habib; Basij,Moslem; Hossein Hosseinpour,Mohammad; Rastegar,Fahimeh; Bagher Nasiri,Mohammad.
Plant materials with insecticidal properties have been traditionally used for generations in some parts of the world. In this study, fumigant toxicity of some essential oils extracted from Rosmarinus officinalis L., Mentha pulegium L., Zataria multiflora, and Citrus sinensis (L.) Osbeck var. hamlin on adults of stored-product pests, including Tribolium castaneum, Sitophilus granarius, Callosobruchus maculatus, and Plodia interpunctella were investigated. Pure essential oils were used in glass vials for the bioassay. LC50 values of Citrus sinensis var. hamlin against T. castaneum, S. granarius, and C. maculatus were 391.28, 367.75, and 223.48 µL L-1 air after 24 h, 362.40, 20.45, and 207.17 µL L-1 air after 48 h, respectively. Furthermore, LC50 values of...
Tipo: Journal article
Palavras-chave: Fumigant toxicity; Toxicidad fumigante.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100010

Socioeconomic Issues in Irrigation Literature: Approaches, Concepts, and Meanings
Provedor de dados: 117
Autores: Montaña,Elma; Pastor,Gabriela; Torres,Laura.
“Knowledge Assessment on Sustainable Water Resources Management for Irrigation” (KASWARMI) project made evident cases of unsuccessful or non sustainable irrigation experiences that could only be explained by the underestimation of deep socioeconomic issues. This involves not only the social factors related to the implementation/adoption of new or better technologies by a wide spectrum of users but also the way in which water use and irrigation projects are conceived, planned and implemented by scientists, politicians and practitioners. The project was interested in assessing the social science inputs irrigation specialists receive. With this objective, this paper presents a state of the art on some selected socioeconomic subjects as they appear in the...
Tipo: Journal article
Palavras-chave: Irrigation; Socioeconomic issues; Social sciences; State of the art.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500006

Effect of Split Nitrogen Applications on Durum Wheat Cultivars in Volcanic Soil
Provedor de dados: 117
Autores: Hirzel,Juan; Matus,Iván; Madariaga,Ricardo.
Durum wheat (Triticum turgidum L. var. durum) is an important crop for the world population and occupies a large cultivated area worldwide. New cultivars need constant improvement of their agronomic management, within which N fertilization is highlighted. Durum wheat is also important in Chile where genetic breeding and agronomic management have been developed to increase yield, industrial, and nutritional grain quality. The objective of this experiment was to determine the appropriate number of N applications during a crop cycle in a volcanic ash soil in South Central Chile. Nitrogen split applications were carried out on three durum wheat cultivars in a Melanoxerands soil during the 2003-2004 and 2004-2005 seasons. A rate of 200 kg ha-1 N was applied at...
Tipo: Journal article
Palavras-chave: Durum wheat; Cultivars; Nitrogen; Split applications; Volcanic soil.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400009

Bayesian analysis of the genetic structure of a Brazilian popcorn germplasm using data from simple sequence repeats (SSR)
Provedor de dados: 117
Autores: Saavedra,Javier; Silva,Tereza Aparecida; Mora,Freddy; Scapim,Carlos Alberto.
Several studies have confirmed that popcorn (Zea mays L. var. everta) has a narrow genetic basis, which affects the quality of breeding programs. In this study, we present a genetic characterization of 420 individuals representing 28 popcorn populations from Brazilian germplasm banks. All individuals were genotyped using 11 microsatellite markers from the Maize Genetics and Genomics Database. A Bayesian clustering approach via Monte Carlo Markov chains was performed to examine the genetic differentiation (Fst values) among different clusters. The results indicate the existence of three distinct and strongly differentiated genetic groups (K = 3). Moreover, the Fst values (calculated among clusters) were significantly different according to Bayesian credible...
Tipo: Journal article
Palavras-chave: Genetic differentiation; Microsatellite markers; Bayesian clustering; Monte Carlo Markov chains.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200003

Growth and Yield Response of Watermelon to in-row Plant Spacings and Mycorrhiza
Provedor de dados: 117
Autores: Ban,Dean; Goreta Ban,Smiljana; Oplanic,Milan; Horvat,Josipa; Novak,Bruno; Zanic,Katja; Znidarcic,Dragan.
Worldwide, a significant increase in watermelon (Citrullus lanatus [Thunb.] Matsum. &amp;amp; Nakai) growing areas has been registered in the last few years. In-row plant spacing has a significant effect on the growth and yield of watermelon, and can enhance competition for water and nutrients. The aim of this study was to investigate the effects of in-row plant spacing (1.0, 1.5, 2.0 and 2.5 m) and arbuscular mycorrhiza (AM) fungi Glomus mosseae inoculations on watermelon growth and yield under field conditions during 2003, 2004, and 2005 year. In 2003, the main vine length, number of leaves, and number of lateral branches were increased quadratically as the in-row plant spacing increased from 1.0 to 2.5. With an increase in the in-row plant spacing the...
Tipo: Journal article
Palavras-chave: Arbuscular mycorrhiza; Fruit; Plant density; Vegetative growth.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400001

A Simulation Model of Mesophytic Perennial Grasslands
Provedor de dados: 117
Autores: Castellaro G,Giorgio; Aguilar G,Claudio; Vera I,Raul; Morales S,Luis.
Grasslands are complex ecosystems and their processes are affected by soil, meteorological, and management variables. In this context, dynamic simulation models are useful to understand these processes and to design grassland use strategies. The aim of this study was to develop and validate a simulation model of perennial pasture growth based on soil and climate variables. A first approach considered that soil fertility levels were adequate; therefore, soil water availability and phytomass level were the main variables affecting pasture growth. The subroutines considered were water balance, pasture growth, and root biomass dynamics. The hypotheses regarding the functioning of the system were formulated as a group of equations which were solved numerically...
Tipo: Journal article
Palavras-chave: Grassland simulation models; Mesophytic grasslands.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300013

Field Performance of a Winged Scarifier as a Function of Soil Compaction and Water Content
Provedor de dados: 117
Autores: Cholaky,Carmen; Cisneros,José M; Balbuena,Roberto.
Initial soil conditions, operational aspects, and tool shape affect the efficiency of soil decompaction. The objective of this study was to evaluate the performance of a winged scarifier as a function of soil compaction and edaphic water content. The experiment was carried out in a typical Hapludoll. Treatments considered two soil compaction levels: high (HC) and low compaction (LC); and three soil water contents: wet (WS), humid (HS), and dry (DS) with 9, 14, and 19% gravimetric water content, respectively. A split-plot randomized block design was applied. Tractive effort, disturbed area, tillage depth, specific resistance, and power were evaluated. Results showed that tractive effort was 17% greater in HC than LC, and in both cases HS was greater than WS...
Tipo: Journal article
Palavras-chave: Agricultural engineering; Winged scarifier; Bulk density; Water content; Compaction.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100016

Crude extracts of Drimys winteri bark to inhibit growth of Gaeumannomyces graminis var. tritici
Provedor de dados: 117
Autores: Zapata,Nelson; Vargas,Marisol; Monsálvez,Manuel; Ceballos,Ricardo.
The aim of this study was to assess the effect of Drimys winteri J.R. Forst. &amp;amp; G. Forst. bark and its extracts, obtained sequentially with n-hexane, acetone, and methanol, against Gaeumannomyces graminis var. tritici (Ggt). Ground bark of D. winteri was mixed with potato dextrose agar growth media at concentrations of 250, 500, 1000, 2000, and 4000 mg L-1 in Petri plates. Each extract was mixed at concentrations of 100, 200, 400, and 800 mg L-1. Petri plates were inoculated in the center with a 5-mm mycelium disk and were incubated at 24 ± 1 ºC. Daily measurements of mycelium radial growth were taken to determine growth rate and growth inhibition (%). A ground bark concentration of 978 mg L-1 was needed to inhibit Ggt growth by 50%, while extracts...
Tipo: Journal article
Palavras-chave: Wheat take-all; Soil borne; Plant extracts; Ggt.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100006

Postharvest Sensory and Phenolic Characterization of ‘Elegant Lady’ and ‘Carson’ Peaches
Provedor de dados: 117
Autores: Infante,Rodrigo; Contador,Loreto; Rubio,Pía; Aros,Danilo; Peña-Neira,Álvaro.
High quality fruits are increasingly demanded along with the need to ensure this attribute to consumers. Thus, this study was aimed at characterizing a melting (‘Elegant Lady’) and a non-melting flesh (‘Carson’) peach (Prunus persica (L.) Batsch) varieties by considering both their bioactive compound contribution and their sensory quality in ripe fruit at harvest and after a prolonged period of cold storage. Cultivars were evaluated at harvest (F0) and after 30 d of cold storage (F30), as well as after a maturation period at 20 °C for both F0 and F30 (R0 and R30, respectively). Fruit weight, flesh firmness, soluble solid content (SSC), titratable acidity (TA), and background color (Hue) were recorded at each stage. Furthermore, total phenol content was...
Tipo: Journal article
Palavras-chave: Quality parameters sensory evaluation total phenols (+)-catechin; HPLC.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300016

Classification of some Linseed (Linum usitatissimum L.) Genotypes for Salinity Tolerance using Germination, Seedling Growth, and Ion Content
Provedor de dados: 117
Autores: Demir Kaya,Mehmet; Day,Sibel; Cikili,Yakup; Arslan,Neset.
Salinity reduces germination, delays emergence, and inhibits seedling growth of linseed (Linum usitatissimum L.) while some varieties are less affected by salinity than others. In this study, we aimed to determine the effects of NaCl levels (0, 5, 10, 20 and 30 dS m-1) on germination and seedling growth of 10 linseed genotypes (lines 87, 89, 104, 114, 193, 194, 209, 215, C-90 and cv. San-85) and to classify the genotypes for salinity tolerance using germination and seedling characteristics. Germination percentage, mean germination time, root and shoot length, seedling fresh and dry weight, Na+ content and Na:K ratio of seedlings were investigated. Classification of linseed genotypes for salinity tolerance was done according to (i) combination of Principal...
Tipo: Journal article
Palavras-chave: NaCl; Tolerance; Cluster; Ion accumulation.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100005

The Effects of Different Fungicides on the Viability of Entomopathogenic Nematodes Steinernema feltiae (Filipjev), S. carpocapsae Weiser, and Heterorhabditis downesi Stock, Griffin &amp;amp; Burnell (Nematoda: Rhabditida) under Laboratory Conditions
Provedor de dados: 117
Autores: Laznik,&amp;#381;iga; Vidrih,Matej; Trdan,Stanislav.
To increase our knowledge on the susceptibility of entomopathogenic nematodes (EPN) species to agrochemicals, the compatibility of the infective juveniles (IJ) of the entomopathogenic nematodes Steinernema feltiae, S. carpocapsae, and Heterorhabditis downesi with 15 chemical fungicides was investigated under laboratory conditions. The effect of direct IJ exposure to fungicides for 24 h was tested in a petri dish at 15, 20, and 25 °C. The results showed that the compatibility of S. feltiae with azoxystrobin was high, and similar findings were obtained for S. carpocapsae (strain C67) and all of the tested fungicides, except for tebuconazole + spiroxamine + triadimenol, maneb, dinocap, and copper (II) hydroxide + metalaxil-M. Nematode H. downesi (strain 3173)...
Tipo: Journal article
Palavras-chave: Compatibility; Fungicides; Viability.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100010

Influence of contrasting environments on seed composition of two quinoa genotypes: nutritional and functional properties
Provedor de dados: 117
Autores: Miranda,Margarita; Vega-Gálvez,Antonio; Martínez,Enrique A; López,Jéssica; Marín,Rosa; Aranda,Mario; Fuentes,Francisco.
Quinoa (Chenopodium quinoa Willd.) in Chile represents a source of germplasm with high nutritional value. However, there is little information available related to quinoa seed quality grown under contrasting environments. In this study we evaluated the changes on seed composition of seeds of two lowland/coastal quinoa genotypes grown under arid (Vicuna) and cold-temperate (Temuco) conditions in Chile. Results showed that in the case of 'Regalona Baer' and 'Villarrica' genotypes the arid location (with irrigation) led to a significant increase (P &lt; 0.05) in grain yield (4.2 and 5.1 t ha-1, respectively), soluble dietary fiber (16.8 ± 0.4 and 28.9 ± 2.1 g kg-1 DM, respectively), vitamin B3 (2.44 ± 0.005 and 2.26 ± 0.04 mg 100 g-1 DM, respectively),...
Tipo: Journal article
Palavras-chave: Chenopodium quinoa; Climate stress; Antioxidant activity; Phenolic compounds; Protein; Mineral content.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200004

Model Validation for Estimating the Leaf Stomatal Conductance in cv. Cabernet Sauvignon Grapevines
Provedor de dados: 117
Autores: Jara-Rojas,Francisco; Ortega-Farías,Samuel; Valdés-Gómez,Héctor; Poblete,Carlos; del Pozo,Alejandro.
The coupled model of assimilation and stomatal conductance (A-g s) was evaluated to estimate leaf stomatal conductance of a drip-irrigated vineyard (Vitis vinifera L. cv. Cabernet Sauvignon) located in the Pencahue Valley (35º22’ S, 71°47’ W, 150 m.a.s.l.), Maule Region, Chile, during the 2003-2004 and the 2004-2005 growing seasons. Additionally, a calibration of the three parameters mesophyll conductance (g m), maximum specific humidity (Dmax) and coupled factor (f0) was applied on vines growing in 35 L pots. An infrared gas analyzer was used to calibrate and evaluate the A-g s which allowed simultaneous measuring of the leaf net CO2 assimilation (A) and stomatal conductance (g s) in 2 to 3 h intervals of time. The calibration indicated that the g m,,...
Tipo: Journal article
Palavras-chave: A-g s model; Photosynthesis; Mesophyll conductance; Stem water potential; Sensitivity analysis.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100011

Organic Versus Conventional Methods of Fertilization and Weed Control in a Long Term Rotation of Cereals in Semiarid Spain
Provedor de dados: 117
Autores: Pardo,Gabriel; Aibar,Joaquín; Ciria,Pilar; Lacasta,Carlos; Lezaún,Juan Antonio; Zaragoza,Carlos.
Under semiarid conditions the response of cereal crops to chemical fertilizers and weed control practices with herbicides is often reduced. In fact, the economic profitability of agricultural production in many dryland regions is critically affected by high costs of inputs and low crop yields. As a solution, cropping systems like organic farming, obtaining similar yields and promoting environmental sustainability by reducing fertilizer and herbicides, could be an alternative to conventional systems. In this study, 23 trials were performed in five semiarid regions of Spain during 5 yr to compare different fertilizers and weed control methods on durum wheat (Triticum durum Desf.) and barley (Hordeum vulgare L.) yields. The following rotation pattern was...
Tipo: Journal article
Palavras-chave: Sustainability; Ecological agriculture; Crop rotation; Compost; Flex-tine harrow.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200002

Influence of Water Deficit on Iron and Zinc Uptake by Matricaria chamomilla L.
Provedor de dados: 117
Autores: Pirzad,Alireza; Darvishzadeh,Reza; Bernousi,Iraj; Hassani,Abbas; Sivritepe,Nuray.
Iron and zinc deficiency are a yield-limiting factor with major implications for field crop production in many agricultural regions of the world; this production is essential source of Fe and Zn in human and animal diets. Two experiments were conducted under greenhouse conditions to evaluate Fe and Zn uptake by German chamomile (Matricaria chamomilla L.) grown under several drought conditions. Treatments were arranged in four irrigation regimes (95%, 80%, 65%, and 50% field capacity) and six irrigation disruptions (stem formation, flower onset, full bloom, first harvest, second harvest, and control without disruption) based on a randomized complete block design with five and four replicates in experiments 1 and 2, respectively. In Experiment 1, the...
Tipo: Journal article
Palavras-chave: Irrigation; Fe; Micronutrients; Zn.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200011

Effect of the Cooling System and 1-MCP on the Incidence of Superficial Scald in ‘Granny Smith’ Apples
Provedor de dados: 117
Autores: Moggia,Claudia; Hernández,Omar; Pereira,Marcia; A. Lobos,Gustavo; Yuri,José Antonio.
A study was carried out to determine the effects of two cooling systems and the application of 1-methylcyclopropene (1-MCP, SmartFreshTM) on the incidence of superficial scald in apples (Malus domestica Borkh.) cv. Granny Smith. Fruit were collected from a commercial orchard (Colbún, Maule Region, Chile) during 2004-2005 season. A completely randomized design was used in a 2 x 2 factorial arrangement, using cooling systems (normal and step-wise cooling) and application of 1-MCP (0 and 625 nL L-1 i.a.) as the main factors. Fruit from normal cooling were kept at 0 °C throughout the storage period (180 days). Step-wise cooling consisted of storing the fruit at 10 °C for 10 days; 4 °C for the next 20 days and 0 °C for the remaining 150 days. Every month,...
Tipo: Journal article
Palavras-chave: Conjugated trienes; Antioxidants; -farnesene; 1-methylcyclopropene; Physiological disorder; Ethylene.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300011

Effect of sewage sludge and sawdust in association with hybrid ryegrass (Lolium x hybrydum Hausskin.) on soil macroaggregates and water content
Provedor de dados: 117
Autores: Sandoval E,Marco; Celis H,José; Bahamondes P,Carlos.
Chilean soils degradation is a serious problem affecting directly the productivity of most of the crops. Some evidence indicates sewage sludge can improve soil physical properties, especially when combined with sawdust. The objective of this work was to evaluate the effect of different mixtures of sewage sludge (LU) and sawdust (RA) on water-stable aggregates and available water content of a degraded Alfisol cropped with hybrid ryegrass (Lolium x hybridum Hausskn.), under greenhouse conditions. The experimental design was a completely randomized with a factorial arrangement of 2 x 9 (ryegrass x rates of sludge and sawdust). Treatments were 25 and 50 Mg LU ha-1 mixed with 10, 25, and 50 Mg RA ha-1. Ratio mixtures of LU/RA were set in pots with hybrid...
Tipo: Journal article
Palavras-chave: Soil aggregation; Biosolids; Remediation; Organic wastes; Degraded soil.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400017

Reduced Doses of a Sulfonylurea Herbicide for Weed Management in Wheat Fields of Punjab, Pakistan
Provedor de dados: 117
Autores: Khaliq,Abdul; Matloob,Amar; Tanveer,Asif; Areeb,Ahsan; Aslam,Farhena; Abbas,Nadeem.
Reduction in herbicide usage without compromising yields can lead to less environmental harm and lower production costs. Field trials were conducted to appraise the efficacy of reduced doses (25, 50, and 75% of the label dose) of a post emergence sulfonylurea herbicide [Atlantis 3.6WG (iodo+mesosulfuron)] to control weeds in wheat (Triticum aestivum L.) fields of Punjab, Pakistan. Below-labeled-doses were quite effective in suppressing total weed density (72-95%) and biomass (83-94%), and wheat grain yield was increased by 22 to 48% over the weedy control, while label dose of iodo+mesosulfuron improved yield by 53%. Iodo+mesosulfuron at 25 and 50% of the label dose inhibited grass weeds by 43 to 64%, albeit their biomass was suppressed by &gt; 80% over...
Tipo: Journal article
Palavras-chave: Reduced herbicide dose; Weed suppression; Efficiency; Wheat yield.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300013

Assesing Bemisia tabaci (Genn.) biotype B resistance in soybean genotypes: Antixenosis and antibiosis
Provedor de dados: 117
Autores: Gonçalves Franco da Silva,José Paulo; Lopes Baldin,Edson Luiz; Santana de Souza,Efrain; Lourenção,André Luiz.
Since it was first reported in Brazil in the 1990s, the B biotype of silverleaf whitefly (Bemisia tabaci Genn., Hemiptera: Aleyrodidae) has been recognized as an important pest in soybeans (Glycine max L.), reducing the productivity of this legume species in some areas of the country. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM). This study evaluated the performance of 10 soybean genotypes prior to whitefly infestation, by testing attractiveness and preference for oviposition in the greenhouse and antibiosis in the laboratory. In a multiple-choice test, 'IAC-17' was the least attractive to insects. In a no-choice test, 'IAC-17' was the least attractive for egg...
Tipo: Journal article
Palavras-chave: Glycine max; Silverleaf whitefly; Host plant resistance; Attractiveness; Non-preference; Trichome.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400009

Application of Oligonucleotide Microarray for the Detection and Genotyping of cry Genes in Bacillu thuringiensis
Provedor de dados: 117
Autores: Xu-Guang,Liu; Fu-Ping,Song; Si-Yuan,Wen; Sheng-Qi,Wang; Da-Fang,Huang; Jie,Zhang.
We have developed a parallel, rapid, high-throughput oligonucleotide microarray-based assay for the reliable detection and genotyping of three cry genes (cry1, cry2 and cry9) in Bacillus thuringiensis (Bt). After the non-polymerase chain reaction (PCR), amplified Bt genomic DNA were fluorescent-labeled using a random primer.   The corresponding oligonucleotide probes were designed for the different cry genes that can hybridize Bt genomic DNA after cluster analysis and were printed on glass slides. This microarray has unambiguously detected and identified the cry genes in 10 isolates and reference Bt. Our data demonstrates that the microarray assay is simple and rapid for the detection and genotyping of genes. This type of assay is also a potentially...
Tipo: Journal article
Palavras-chave: Oligonucleotide microarray; Cry genes; Genotyping; Random primer labeling; Bioinformatics.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200004

Greenhouse Gas (CO2 AND N2O) Emissions from Soils: A Review
Provedor de dados: 117
Autores: Muñoz,Cristina; Paulino,Leandro; Monreal,Carlos; Zagal,Erick.
In agricultural activities, the main greenhouse gases (GHG) are those related to C and N global cycles. The impact of agriculture on GHG emissions has become a key issue, especially when considering that natural C and N cycles are influenced by agricultural development. This review focuses on CO2 and N2O soil emissions in terrestrial ecosystems, with emphasis in Chilean and similar agro-ecosystems around the world. The influence of land use and crop management practices on CO2 and N2O emissions is analyzed; some mitigation measures to reduce such emissions are also discussed here. More knowledge on the biological processes that promote of GHG emissions from soil will allow creating opportunities for agricultural development under friendly-environmental...
Tipo: Journal article
Palavras-chave: Global warming; Carbon dioxide; Nitrous oxide; Soil biological processes; Soil organic carbon; Nitrification; Denitrification.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300016

Honey as a bioindicator of arsenic contamination due to volcanic and mining activities in Chile
Provedor de dados: 117
Autores: Bastías,José M; Jambon,Philippe; Muñoz,Ociel; Manquián,Nimia; Bahamonde,Patricia; Neira,Miguel.
The content of heavy metals in honey is indicative of natural or anthropogenic pollution and has therefore been proposed as a feasible bioindicator for arsenic contamination in different regions of Chile. Total arsenic (t-As) and inorganic As (i-As) concentrations were determined in 227 samples of honey harvested during the years 2007, 2008, and 2009 in the areas of San Pedro de Atacama, Atacama, Chiloé, and Futaleufú, with the last town located 156 km from the Chaitén Volcano (latest eruption in 2008). These analyses were conducted using an atomic absorption spectrophotometer coupled with a hydride generator. In the honey samples, the concentrations of t-As ranged from 2.2 to 171.9 &amp;#956;g kg-1, and the i-As concentrations ranged from none detected...
Tipo: Journal article
Palavras-chave: Honey; Bioindicator; Total arsenic; Inorganic arsenic; Pollution.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200010

A Rainfall Simulator for the in situ Study of Superficial Runoff and Soil Erosion
Provedor de dados: 117
Autores: Sangüesa,Claudia; Arumí,José; Pizarro,Roberto; Link,Oscar.
A rainfall simulator is an important tool for the study of runoff generation and soil loss because it can be used either under laboratory conditions, or in disturbed or natural soil. The objective of this study was to describe the design and operation of a rainfall simulator to evaluate soil loss in situ. The rainfall simulator has four full-cone spray nozzles with a Unijet system mounted in a straight line pipe configuration, and easily transported and assembled. Simulated rainfall uniformity was evaluated in the laboratory, whereas the applicability of the simulator in natural soil erosion plot conditions in an experimental field with different slopes was tested by quantifying runoff and evaluating soil erosion. Twenty simulations were carried out in the...
Tipo: Journal article
Palavras-chave: Soil erosion; Superficial runoff; Erosion plot; Uniformity of rain.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100019

Extraction and isolation of anti-tryptic castor-bean (Ricinus communis L.) substances and their effects on Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae)
Provedor de dados: 117
Autores: Ramos,Vinicius; Alves,Dejane; Braga,Mariana; Carvalho,Geraldo; Santos,Custódio.
The search for alternative methods aiming to the control of agricultural pests that cause less environmental impact has been a recurring theme in several studies. For this purpose, the factors influencing the extraction and isolation of the trypsin inhibitor found in castor-bean (Ricinus communis L.) cake and seeds were studied, and its effect on the development of fall armyworm Spodoptera frugiperda (Smith, 1797) was evaluated. Therefore, the type and proportion of the solvent (w/v), extraction period and oil content were evaluated. The castor-bean cake extract with oil content of 20% in water at a ratio 1:40 (w/v) for 30 min showed the greatest trypsin inhibition, with 21.23 mUTI g-1 seed. The isolation of the trypsin inhibitor contained in the extract...
Tipo: Journal article
Palavras-chave: Zea mays; Fall armyworm; Ricinus communis; Trypsin inhibitor; Alternative control.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200007

Bioactivity of a water extract of boldus (Peumus boldus Molina) against Spodoptera frugiperda (J.E. Smith) and Helicoverpa zea Boddie (Lepidoptera: Noctuidae)
Provedor de dados: 117
Autores: Silva,Gonzalo; Rodríguez,J. Concepción; Blanco,Carlos A; Lagunes,Angel.
The insecticidal properties of water-extract of Peumus boldus Molina and its effect on the development cycle and feeding habits of Spodoptera frugiperda J.E. Smith and Helicoverpa zea Boddie were evaluated under laboratory conditions in concentrations of 0.25, 0.5, 1.0, 2.0, 4.0, and 8.0% (w/w). Spodoptera frugiperda was the most susceptible with 75% mortality at 7 d at 8% P. boldus concentration, while H. zea had only 30% mortality. LC50 was 2.31 mL kg-1 for S. frugiperda and 16.05 mL kg¹ for H. zea. When the extract concentration increased in the diet, larval size and weight, percentage of pupation and number of adults decreased, and the time required to reach those states was greater. Neonate larvae fed primarily on the diet with the lower extract...
Tipo: Journal article
Palavras-chave: Fall armyworm; Corn earworm; Botanical insecticides; Nutritional indexes.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200008

Seedling Establishment and Forage Accumulation of ‘Ceres Tonic’ Plantain in Pure Stands and in Grass Mixtures
Provedor de dados: 117
Autores: Cid,M. Silvia; Brizuela,Miguel A; Mendiburu,Analía; Gariglio,Juan M.
This study evaluates the balance of species 2 mo after sowing, its effects on seasonal and annual dry matter accumulation of Plantago lanceolata L. ‘Ceres Tonic’ sown in pure stands, in binary mixtures with three grasses, and different initial growth rates: annual ryegrass (Lolium multiflorum Lam.), tall fescue (Festuca arundinacea Schreb.), and orchard grass (Dactylis glomerata L.). Plantain monocultures were sown at three densities (4, 8, and 12 kg seed ha-1), while halved densities were used in the mixtures. Each grass was sown at the density that is typical for the region (annual ryegrass = 30, tall fescue = 15, and orchard grass = 6 kg seed ha-1). The trial was carried out in Balcarce (37º45’ S, 58º18’ W; 130 m.a.s.l.), Argentina in 1.4 × 5 m plots...
Tipo: Journal article
Palavras-chave: Plant density; Seasonal forage.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300004

Identification and Biological Characterization of Isolates with Activity Inhibitive against Macrophomina phaseolina (Tassi) Goid
Provedor de dados: 117
Autores: Gacitúa A,Sandra; Valiente F,Carolina; Díaz P,Katy; Hernández C,José; Uribe M,Matilde; Sanfuentes V,Eugenio.
The Macrophomina phaseolina (Tassi) Goid. fungus, causal agent of charcoal root rot, is considered one of the most important pathogens in forest nurseries. Recent studies in Chile have verified the antagonistic capacity of diverse bacterial isolates against M. phaseolina in vitro as well as in field testing. The objectives of this study were to identify Bacillus isolates and establish the mechanisms of antagonism against M. phaseolina. Isolates were identified with the bioMérieux biochemical kit. Tests were done in vitro and consisted in determining the production of volatile metabolites, siderophores, and the effect of different culture temperatures (20, 25, 30, and 35 °C) on the production of diffusible metabolites and inhibition of mycelial growth of...
Tipo: Journal article
Palavras-chave: Biocontrol; Forest nursery.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400007

Variation of water potential and trunk diameter answer as sensitivity to the water availability in table grapes
Provedor de dados: 117
Autores: Silva-Contreras,Claudio; Sellés-Von Schouwen,Gabriel; Ferreyra-Espada,Raul; Silva-Robledo,Herman.
Variation in trunk diameter (TDV) has been proposed as an indicator of the water status of grape vines, with apparently contradictory results. In Vitis vinifera L. var. Crimson Seedless we evaluated the water potential (&amp;#936;), an indicator normally used to determine the water status of grapes, and TDV, comparing two irrigation treatments which restored 100% or 50% of the ETc, to compare the sensitivity of these two indicators to a decrease in soil water. Two evaluation periods of 23 d each were used, the first during the exponential growth phase and the second in the post-veraison period, when the trunk stops growing. In both periods TDV showed coefficients of variation greater than 25%, compared to the 7-10% recorded for water potential. However,...
Tipo: Journal article
Palavras-chave: Water potential; Variable displacement sensor; Sensitivity; Itis vinifera.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400001

Commercial Digital Camera to Estimate Postharvest Leaf Area Index in Vitis vinifera L. cv. Cabernet Sauvignon on a Vertical Trellis
Provedor de dados: 117
Autores: Espinosa L.,Miguel; Acuña C.,Eduardo; Espinosa B.,Miguel; Barrera B.,Juan.
The leaf area index (LAI) of a vineyard (Vitis vinifera L.) cv. Cabernet Sauvignon located in the commune of Cauquenes, Maule Region in Chile, was estimated from digital images obtained with a commercial camera using two indirect methods: Leaf Area Gap and Brightness (LAGB) and -Photogrammetric Leaf Area Quantification System (PLAQS). The latter requires deleafing of the grapevine. In a normalized difference vegetation index (NDVI) map, three points of vine vigor were selected: high, medium, and low for which horizontal and vertical images were obtained. Images were filtered with the Arc View GIS 3.1 program to provide only leaf images and corresponding pixel numbers. Image area and square meters per linear meter were calculated. The best models were...
Tipo: Journal article
Palavras-chave: Vitis vinifera; Leaf area index; Digital image; Photographic camera.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200015

Methods to Break Seed Dormancy of Rhynchosia capitata, a Summer Annual Weed
Provedor de dados: 117
Autores: Haider Ali,Hafiz; Tanveer,Asif; Ather Nadeem,Muhammad; Naeem Asghar,Hafiz.
Dormancy of weed seeds is a significant feature contributing to their survival rate since it helps the weeds to avoid herbicides and other weeding practices along with unfavorable environmental conditions. We investigated the effects of different dormancy breaking treatments on the germination of Rhynchosia capitata, a common summer annual weed, which is emerging as a weed threat in Pakistan. Seeds were soaked in thiourea, KNO3, HCl, HNO3, and H2SO4, and they were also mechanically scarified (sandpaper). Results indicated that R. capitata seeds show signs of physical dormancy that is mainly due to the impermeability of their coat. Mechanical scarification and acid scarification (soaking of seeds in H2SO4 for 60 and 80 min and in HCl for 12 and 15 h) were...
Tipo: Journal article
Palavras-chave: HCl; HNO3; H2SO4; Dormancy; Germination.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300021

Fumigant Toxicity of Crushed Bulbs of Two Allium Species to Callosobruchus maculatus (Fabricius) (Coleoptera: Bruchidae)
Provedor de dados: 117
Autores: Ofuya,T.I; Olotuah,O.F; Ogunsola,O.J.
Fumigant toxicity of crushed fresh bulbs of Allium sativum L. and A. cepa L. to the Callosobruchus maculatus (Fabricius), a major pest of stored cowpea (Vigna unguiculata (L.) Walp.) seeds was assessed under laboratory conditions in Akure, Nigeria. In the tests, 20 g of infested cowpea seeds were suspended in a piece of muslin cloth, over an amount of crushed bulb in a container with a tightly fitted lid. Adult emergence was completely prevented from freshly laid eggs of C. maculatus on cowpea seeds that was fumigated with 6.0 g or more of crushed bulbs of A. sativum. Such fumigated seeds were not holed at all. Other amounts of A. sativum tested (1.0, 2.0, 3.0, 4.0 and 5.0 g) significantly reduced C. maculatus adult emergence from fumigated eggs and seed...
Tipo: Journal article
Palavras-chave: Infestation; Seed holing; Pesticide; Volatiles; Essential oils.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300019

Validation of a leaf area prediction model proposed for rose
Provedor de dados: 117
Autores: Fascella,Giancarlo; Darwich,Salem; Rouphael,Youssef.
Leaf area (LA) is a valuable key for evaluating plant growth, therefore accurate, simple, and nondestructive methods for LA determination are important for physiological and agronomic studies. A LA prediction model based on leaf length (L) and width (W) and developed under greenhouse on 14 cultivars of rose (Rosa hybr.*) was validated on a different cultivar of R. hybrida 'Red France' and on a wild rose species (Rosa sempervirens L.) grown under open-field conditions with two light environments: ambient and 50% shade. Comparisons between measured vs. calculated LA using the following model: LA (cm²) = 0.56 + 0.717 LW, showed a high degree of correlation (R² &gt; 0.95) and provided quantitative evidence of the validity of the LA prediction model. Calculated...
Tipo: Journal article
Palavras-chave: Leaf length; Leaf width; Rosa hybr; Rosa sempervirens; Light environments; Regression analysis; Model validation.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100011

Latitudinal Analysis of Rainfall Intensity and Mean Annual Precipitation in Chile
Provedor de dados: 117
Autores: Pizarro,Roberto; Valdés,Rodrigo; García-Chevesich,Pablo; Vallejos,Carlos; Sangüesa,Claudia; Morales,Carolina; Balocchi,Francisco; Abarza,Alejandro; Fuentes,Roberto.
The study and analysis of precipitation has become a crucial tool in understanding the temporal and spatial behavior of water resources, in terms of availability and impact on extreme events. The objective of this study was to evaluate different rainfall parameters (intensities for 1-h duration D = 1 h and return periods of T = 5 and 100 yr, and mean annual precipitation) for different latitudinal and climatic zones in Chile. We analyzed the information recorded on thousands of pluvial bands and rain gauges for 49 stations; this because it is unclear how rainfall intensities change along the country (though total amounts do), in addition to a lack of literature focused on ranges and amounts on the behavior of rainfall variables. The Gumbel probability...
Tipo: Journal article
Palavras-chave: Precipitation; Frequency-duration-intensity curves; IDF curves; Rainfall intensity.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200014

Effect of Nitrogen Source on Some Rhizospheric Properties and Persistence of my Corrhizal Fungal Propagules in an Andisol
Provedor de dados: 117
Autores: Cornejo,Pablo; Rubio,Rosa; Borie,Fernando.
Nitrogen fertilization influences plant growth and rhizospheric properties, affecting the functionality and persistence of arbuscular mycorrhizal fungi (AMF). In order to analyze the effect of two N-sources (NH4+ and NO3-) on the persistence of AMF propagules (colonized root, mycelium and spores) and some rhizospheric parameters (pH, P available), a greenhouse experiment was carried out using two wheat (Triticum aestivum L.) cvs. Otto and Metrenco, which were grown in an Andisol. Plant biomass was determined at the dry grain stage (Zadocks 99, 150 days after sowing, DAS), the density of AMF propagules was determined three months later (240 DAS), and pH and available P were determined at both stages. The results showed that N-source and cultivar influenced...
Tipo: Journal article
Palavras-chave: Acidic soils; Available P; Wheat cultivars; Nitrogen fertilization; Rhizospheric pH.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200001

Nutritional Quality of Beef Produced in Chile from Different Production Systems
Provedor de dados: 117
Autores: Morales,Rodrigo; Folch,Carolina; Iraira,Sergio; Teuber,Nolberto; Realini,Carolina E.
In recent years, beef industry has improved production processes to ensure quality and certification for overseas meat markets. However, there is limited scientific information about the nutritional quality of beef from Chile. The aim of the present study was to evaluate the nutritional quality of beef produced in Chile from different production systems classified according to the type of finishing diet. Two-hundred and five animals from 13 livestock farms were used, 80 steers were finished on grazing pasture, 79 on pasture supplemented with grain or concentrate and 46 steers were finished on a typical feedlot system in the central zone of Chile. Longissimus thoracis intramuscular fat, fatty acid composition and cholesterol content were determined. Beef...
Tipo: Journal article
Palavras-chave: Fatty acids; Pasture; Feedlot; Chilean beef quality.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100013

Field bindweed (Convolvulus arvensis L.) and redroot pigweed (Amaranthus retroflexus L.) control in potato by pre- or post-emergence applied flumioxazin and sulfosulfuron
Provedor de dados: 117
Autores: Vasilakoglou,Ioannis; Dhima,Kico; Paschalidis,Konstantinos; Gatsis,Thomas; Zacharis,Konstantinos; Galanis,Miltos.
Field bindweed (Convolvulus arvensis L.) is one of the most serious weeds in potato (Solanum tuberosum L.), but selective herbicides controlling this weed have not been reported. A field experiment was conducted in 2010 and repeated in 2011 in Greece to study the efficacy of herbicides flumioxazin and sulfosulfuron, applied pre- or post-emergence, on field bindweed and redroot pigweed (Amaranthus retroflexus L.), as well as their phytotoxicity on potato. Gas chromatography-mass spectrography (GC-MS) and high-performance liquid chromatography (HPLC) analyses were conducted for possible herbicide residues in potato tubers. Also, the efficacy of these herbicides on field bindweed generated from root fragments was investigated in greenhouse pot experiments. In...
Tipo: Journal article
Palavras-chave: Herbicide residues; Phytotoxicity; Solanum tuberosum.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100004

Implications of the Structural Change in Dairy Products Trade on Milk Price Paid to Producers in Chile
Provedor de dados: 117
Autores: Engler,Alejandra; Nahuelhual,Laura.
Since 1990 row milk production has exhibited a rapid increase from 890 million liters in 1990 to 1,818 million in 2006. The excess production has allowed for the expansion of the export sector, converting Chile in a net exporter in 2001. A relevant question in this new market scenario is how this structural change can affect milk prices paid to producers in Chile. The consequences of this structural change were explored in this study using a Vector Error Correction (VEC) model and cointegration analysis. The results indicated that the domestic, CIF (Cost, Insurance, Freight) and FOB (Free On Board) prices were cointegrated, implying that changes in the import and export prices are transmitted to the domestic market affecting the milk price paid to...
Tipo: Journal article
Palavras-chave: Milk market; International trade; Vector error correction; Persistence profiles.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200006

Prediction of the Nutritive Value of Pasture Silage by Near Infrared Spectroscopy (NIRS)
Provedor de dados: 117
Autores: Restaino,Ernesto A; Fernández,Enrique G; La Manna,Alejandro; Cozzolino,Daniel.
The aim of this study was to investigate the use of near infrared reflectance (NIRS) spectroscopy to predict the nutritive value of silages from pastures and to assess the effect of silage structure type (e.g. bunker and bag silos) on the NIRS predictions. Samples (n = 120) were sourced from commercial farms and analyzed in a NIRS monochromator instrument (NIR Systems, Silver Spring, Maryland, USA) using wavelengths between 400 and 2500 nm in reflectance. Calibration models were developed between chemical and NIRS spectral data using partial least squares (PLS) regression. The coefficients of determination in calibration (R²) and the standard error in cross validation (SECV) were 0.73 (SECV: 1.2%), 0.81 (SECV: 2.0%), 0.75 (SECV: 6.6%), 0.80 (SECV: 6.7%),...
Tipo: Journal article
Palavras-chave: Silage; Nutritive value; Near infrared reflectance spectroscopy; Pastures.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400011

Effects of Hydrogen Cyanamide on the Floral Morphogenesis of Kiwifruit Buds
Provedor de dados: 117
Autores: Engin,Hakan; Gökbayrak,Zeliha; Dardeniz,Alper.
The influence of hydrogen cyanamide (HC) on the flower bud development of kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang &amp;amp; A.R. Ferguson). ‘Hayward’ was studied. The bud samples were taken every 5-10 d starting from dormant season (March) and fixed in FAA (10% formalin, 50% ethanol, 5% glacial acetic acid). Flower bud development was compared in three HC concentrations and the control. 1%, 2%, and 3% of HC was applied 35 d before the expected natural bud break. During the onset of bud break, only 57.6% of control buds had sepal primordia developed. On the other hand, HC treated buds had almost completed their stamen formation and started stigma primordia. When the control vines were in advanced bud break, gynoecial plateau already began to...
Tipo: Journal article
Palavras-chave: Ovule initiation; Floral formation; Flower primordia.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300018

No direct effects of resistant soybean cultiva IAC-24 on Podisus nigrispinus (Heteroptera: Pentatomidae)
Provedor de dados: 117
Autores: Cola Zanuncio,José; Azevedo de Freitas,Fernando; de Souza Tavares,Wagner; Lourenção,André Luiz; Vinha Zanuncio,Teresinha; Serrão,José Eduardo.
The parameters of survival, development and reproduction of Podisus nigrispinus Dallas, 1851 (Heteroptera: Pentatomidae) may be affected by feeding on soybean (Glycine max L. Merr.; Fabaceae) cultivars. The direct effect was evaluated of the insect-resistant soybean 'IAC-24' (insect-susceptible soybean 'UFVS-2006' + pupae of Tenebrio molitor L., 1758 Coleoptera: Tenebrionidae versus 'IAC-24' plants + pupae of T. molitor) in the nymph and adult stages of the predator P. nigrispinus. The duration of the nymph stage was similar between treatments, but 'IAC-24' reduced the duration of the IV instar of this predator. The survival of P. nigrispinus was similar between treatments in the instars I, II, IV and V and in the nymph stage, but the survival of the III...
Tipo: Journal article
Palavras-chave: Asopinae; Biological control; Integrated pest management; Predator; Soybean.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400011

Land use impacts on physical-based soil organic matter fractions on three hillside Ferrasols in Mexico
Provedor de dados: 117
Autores: Matus,Francisco; Hidalgo,Claudia; Monreal,Carlos; Estrada,Isabel; Fuentes,Mariela; Etchevers,Jorge.
The effects of cultivation in hillside (&gt; 30% slope) on soil C and N stocks after forest clearance and subsequent cultivation in new re-growth forest sites not always induce rapid soil organic matter (SOM) loss in subtropical areas. In the present study we evaluated the sensitivity to SOM changes of material floatable in water (Fw), coarse sand (&gt; 250 mm), fine sand (50-250 mm), silt (2-50 mm) and clay (0-2 mm) fractions by the impact of cultivation of Mexican Ferrasols. This research also determined the relative degree of C and N saturation in the silt and clay size particles. The soil physical fractions were obtained after ultrasonic vibration and sedimentation. Soil organic matter stock (0-20 cm depth) in cultivated sites ranged from 54 to 146 Mg...
Tipo: Journal article
Palavras-chave: Soil C and N; Sand-size; SOM saturation; Ultrasonic dispersion.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200014

Tomato Infrared Drying: Modeling and some Coefficients of the Dehydration Process
Provedor de dados: 117
Autores: Cesar Corrêa,Paulo; Horta de Oliveira,Gabriel Henrique; Machado Baptestini,Fernanda; Martins Silva Diniz,Mayra Darliane; Almeida da Paixão,Aline.
Infrared dehydration is more advantageous than the convective system under similar conditions, and studying this process is important to further develop equipment and procedures. Thus, the aim of this work was to study the dehydration process of tomato (Solanum lycopersicum L.) slices obtained by infrared drying at three different maturity stages throughout two different procedures: Firstly, the drying model was determined by applying the mass and energy balances under wet bulb temperature for the constant drying rate period and secondly, the mass effective diffusion coefficient was determined throughout the experimental data and the theory of diffusion of the liquid phase for the decreasing drying rate period. Tomato fruits cv. Santa Cruz were used. Three...
Tipo: Journal article
Palavras-chave: Critical moisture content; Diffusion; Finite element method; Heat and mass transfer; Mathematical modeling.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200015

Sustainable Water Resources Management for Irrigated Agriculture in Latin America
Provedor de dados: 117
Autores: Billib,Max; Holzapfel,Eduardo A; Fernández-Cirelli,Alicia.
Tipo: Journal article
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500001

Evaluation of Risk Factors in Agriculture: An Application of the Analytical Hierarchical Process (AHP) Methodology
Provedor de dados: 117
Autores: Toledo,Roger; Engler,Alejandra; Ahumada,Víctor.
Risk in the agricultural sector has multiple dimensions or factors and prioritization of these can support decision making. On the other hand, knowing the importance of these risk factors for distinct agricultural activities and how they vary according to geographic zone constitutes relevant information for agricultural development. The objective of this study was to prioritize risk factors that are highly relevant for farmers in Central South Chile. The multi-criteria Analytical Hierarchical Process (AHP) methodology was used to define a decision structure with four risk factors or criteria: climate, price and direct cost variability, human factor, and commercialization. In general, results obtained showed that there are no important imbalances in the...
Tipo: Journal article
Palavras-chave: Risk analysis; AHP; Multi-criteria decisions.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100014

Administration and Management of Irrigation Water in 24 User Organizations in Chile
Provedor de dados: 117
Autores: Jorge,Jara; López,Marco A; San Martín,Álvaro; Salgado,Luis; Melo,Ovidio.
Approximately 85% of the water consumed in Chile is destined to agricultural irrigation and is managed by the users themselves. This study analyzed the price that irrigation water users pay to their Water User Associations (WUAs) to which they belong and the relationship of this price to the professional level and performance of the WUAs. The study included 24 WUAs: 10 River Administration Boards (JV) and 14 Irrigation Canal Associations (AC). The annual operational budget of each WUA, the price paid by users and the management capacities of the board of directors of each WUA were compared. The study also determined the relative value of user payments to WUAs as a proportion of total production costs of the main crops in each zone. The variability of user...
Tipo: Journal article
Palavras-chave: Water cost; Water users associations; WUAs; Water canal associations; River administration board.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200012

Evaluation of Yield Component Traits of Honeybee-Pollinated (Apis mellifera L.)Rapeseed Canola (Brassica napus L.)
Provedor de dados: 117
Autores: Araneda Durán,Ximena; Breve Ulloa,Rodrigo; Aguilera Carrillo,José; Lavín Contreras,Jorge; Toneatti Bastidas,Marcelo.
Recent introduction of hybrid varieties raises the question if bees (Apis mellifera L.) contribute as pollinator agents in developing the full yield potential of rapeseed (Brassica napus L.). In order to evaluate the yield achieved by B. napus cv. Artus pollinated by A. mellifera testing was carried out in the district of Freire, La Araucanía Region, Chile. This consisted in isolating or excluding rapeseed plants from pollinators with exclusion cages. Treatments applied were total exclusion (T1), partial exclusion (T2) and free pollination (T0) with a density of 6.5 hives ha-1, in order to determine the following yield components traits: grains per silique, siliques per plant, 1000 grain weight and yield. The experimental design used was randomized...
Tipo: Journal article
Palavras-chave: Bee hives; Pollination.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200014

Insecticidal Properties of Peumus boldus Molina Powder Used Alone and Mixed with Lime Against Sitophilus zeamais Motschulsky (Coleopter: Curculionidae)
Provedor de dados: 117
Autores: Bustos-Figueroa,Gabriel; Osses-Ruiz,Francisco; Silva-Aguayo,Gonzalo; Tapia-Vargas,Maritza; Hepp-Gallo,Ruperto; Rodríguez-Maciel,J. Concepción.
The insecticidal properties of boldus (Peumus boldus Molina) powder used alone and mixed with lime against adults of maize weevil (Sitophilus zeamais Motschulsky) were evaluated under laboratory conditions. Additionally, aeration effects (presence or absence) and temperature (room temperature vs. 3 ºC) on insecticidal properties were studied over time. A mortality rate of 100% was observed at 20 g kg-1 (w/w) of P. boldus powder when used alone and mixed with lime in proportions of 50:50, 60:40, and 80:20. The 50% lethal concentration (LC50) for all treatments was &lt; 5 g kg-1, while LC90 was 11 g kg-1. Mixing corn grains with different insecticidal treatments did not affect maize germination. Temperature and aeration did not influence mortality of maize...
Tipo: Journal article
Palavras-chave: Boldus; Maize weevil; Stored corn.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300007

Ruminal Degradability of Dry Matter and Crude Protein from Moist Dehulled Lupin and Extruded Rapeseed Meal
Provedor de dados: 117
Autores: Barchiesi-Ferrari,Claudia; Anrique,René.
The flow of ruminal undegradable protein (RUP) to the small intestine can be increased if ruminal degradation of dietary protein is reduced. The objective of this study was to evaluate the effect of extrusion on ruminal degradability of dry matter (DM) and crude protein (CP) from dehulled lupin (Lupinus albus L.) (DL) and rapeseed (Brassica napus L.) meal (RM). Unextruded soybean (Glicine max L.) meal (SBM) was used as a control. The DL was extruded at 130 ºC with 20% moisture and RM was extruded at 120 ºC with 20% moisture. Ruminal degradability was evaluated in situ by incubating feed samples for 2, 4, 8, 12, 24, and 48 h of fermentation in the rumen using three rumen-fistulated dairy cows. Values of CP soluble fraction (“a”) in SBM, DL, extruded...
Tipo: Journal article
Palavras-chave: Extrusion; Protein supplements; Protein degradation; Soybean meal; Cattle.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300014

Decrease in Pupation and Adult Emergence of Plutella xylostella (L.) treated with Hexaflumuron
Provedor de dados: 117
Autores: Mahmoudvand,Mohammad; Abbasipour,Habib; Sheikhi Garjan,Aziz; Reza Bandani,Ali.
The oligophagous pest Plutella xylostella (L.) is a major crucifer pest in Tehran Province, Iran. Hexaflumuron is an insect growth regulator insecticide with good effects on immature insect stages. The objective of this study was to investigate the effects of two sublethal concentrations (LC10 and LC25) of hexaflumuron on some biological parameters of P. xylostella larvae, such as birth rate (b), death rate (d), finite rate of increase (&amp;#955;), generation time (T), sex ratio, pupation rate, and adult emergence. Results showed that hexaflumuron decreased the total number of eggs and oviposition and post-oviposition periods, pupation, and adult emergence in the treated generation, b, and &amp;#955;. Hexaflumuron also increased T, d, and the...
Tipo: Journal article
Palavras-chave: Hexaflumuron; Sublethal; Birth rate; Death rate; Oviposition period.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200007

Preliminary Evaluation of 29 Olive (Olea europaea L.) Cultivars for Production and Alternate Bearing, in the Huasco Valley, Northern Chile
Provedor de dados: 117
Autores: Tapia C,Francisco; Mora,Freddy; Santos,Alexandra I.
There is increasing interest in the development of intensively managed olive orchards (Olea europaea L.) in northern Chile. The selection of specific varieties that perform well on a particular site is considered crucial to maximizing productivity. The present study was undertaken to evaluate the productive performance of 29 varieties of olive in the Huasco Valley (28°34' S, 70°47' W), Northern Chile.The traits evaluated were: mean olive production per tree considering a longitudinal (PML) analysis over a period of five years, 2003 to 2007, total olive production in the same period (PA03-07) and alternate bearing index (ABI). The effect of variety was highly significant (p &lt; 0.01) for all traits. In the field trial, IAP was moderate (0.52), with PML...
Tipo: Journal article
Palavras-chave: Olive fruit; Alternate bearing.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300004

Alternative management of a problematic weed of wheat Avena fatua L. by metabolites of Trichoderma
Provedor de dados: 117
Autores: Javaid,Arshad; Ali,Sajjad.
Wild oat (Avena fatua L.) is a problematic weed of wheat (Triticum aestivum L.) in Pakistan. The present study was designed to evaluate the herbicidal activity of culture filtrates of four Trichoderma spp., namely T. harzianum, T. pseudokoningii, T. reesei and T. viride, against this weed species. In a laboratory bioassay, original (100%) and diluted (50%) culture filtrates of T. harzianum and T. pseudokoningii significantly reduced shoot and root growth of A. fatua seedlings. Only original culture filtrates of T. reesei exhibited significant effects, while the effect of filtrates of T. viride was insignificant against shoot and root growth of the target weed species. Generally, original concentrations of culture filtrates of all Trichoderma spp., except...
Tipo: Journal article
Palavras-chave: Alternative herbicides; Fungal metabolites.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200004

Prediction of the Composition of Fresh Pastures by Near Infrared Reflectance or Interactance-Reflectance Spectroscopy
Provedor de dados: 117
Autores: Alomar,Daniel; Fuchslocher,Rita; Cuevas,José; Mardones,Rodrigo; Cuevas,Emilio.
Fast and precise analytical tools can contribute to optimize pasture management decisions. This work was carried out to evaluate the potential of one such technique, near infrared spectroscopy (NIRS), to predict the nutritional value of pastures without previous drying of the samples, comparing two forms of collecting the spectra: reflectance, or interactance-reflectance (fiber optic probe). Samples (n = 107) from different swards were taken across the humid and temperate regions (Los Ríos and Los Lagos) of southern Chile. Once their spectra were collected, dry matter (DM) and several chemical constituents, such as crude protein (CP), metabolizable energy (ME), neutral (NDF) and acid detergent fiber (ADF), soluble carbohydrates (SC), soluble crude protein...
Tipo: Journal article
Palavras-chave: Pasture composition; NIR prediction; Near infrared reflectance spectroscopy; Fresh pastures; Fiber optics.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200009

Fecal Contamination of Groundwater in a Small Rural Dryland Watershed in Central Chile
Provedor de dados: 117
Autores: Valenzuela,Mariela; Lagos,Bernardo; Claret,Marcelino; Mondaca,María A; Pérez,Claudio; Parra,Oscar.
Research on microbiological groundwater quality was conducted in Chile in a rural watershed that has almost no other water source. Forty-two wells were randomly selected and levels of indicator bacteria - total coliforms (TC), fecal coliforms (FC), and fecal streptococci (FS) - were repeatedly measured during the four seasons of 2005. The aim of this study was to characterize microbiological groundwater quality, relate indicator levels to certain watershed features and management characteristics which are likely to affect water quality. The dynamics of seasonal temporal contamination was determined with statistical analyses of indicator organism concentrations. Nonparametric tests were used to analyze relationships between bacterial indicators in well...
Tipo: Journal article
Palavras-chave: Biological contamination; Bacteria; Water quality; Environmental pollution.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200013

Modeling Isosteric Heat of Soya Bean for Desorption Energy Estimation Using Neural Network Approach
Provedor de dados: 117
Autores: Amiri Chayjan,Reza; Esna-Ashari,Mahmood.
Sorption isotherm of soya bean (Glycine max (L.) Merr.) was obtained by the dynamic experimental method. Artificial Neural Networks (ANNs) were used for modeling soya bean equilibrium moisture content (EMC). Thermodynamic equations and trained ANN for prediction of two thermodynamic properties of net isosteric heat and entropy of soya bean were utilized. The ANN models were better compared with mathematical models. In this study, the isosteric heat and entropy of sorption of soya bean were separately predicted by two power models as a EMC function. Predictive power of the models was high (R² &amp;#8776; 0.99). At the moisture content above 11% (dry basis, db), isosteric heat and entropy of sorption of soya bean were smoothly decreased, while they were...
Tipo: Journal article
Palavras-chave: Back propagation; Entropy; Isosteric heat; Sorption isotherm; Soya bean.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400012

Composition and Bioactive Properties of Yerba Mate (llex paraguariensis A. St.-Hil.): A Review
Provedor de dados: 117
Autores: Burris,Kellie P; Harte,Federico M; Michael Davidson,P; Neal Stewart Jr,C; Zivanovic,Svetlana.
Yerba Mate is a popular tea beverage produced and consumed in the South American countries of Argentina, Brazil, Chile, Paraguay, and Uruguay, and is processed from the leaves and stems of Ilex paraguariensis A. St.-Hil., a perennial shrub from the Aquifoliaceae family. Production occurs in six stages: harvesting older leaves and small stems, roasting by direct fire, drying under hot air, milling to specified size, aging to acquire optimal sensory attributes, and final packaging. While grown and consumed for centuries in South America, its popularity is increasing in the United States because of demand by consumers for healthier, more natural foods, its filling a niche for a different type of tea beverage, and for Yerba Mate's potential health benefits -...
Tipo: Journal article
Palavras-chave: Antioxidant; Antimicrobials; Natural products; Yerba mate; Tea.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200016

Allelopathic effects of aqueous and organic fractions of Euphorbia dracunculoides Lam. on germination and seedling growth of chickpea and wheat
Provedor de dados: 117
Autores: Tanveer,Asif; Kamran Jabbar,Muhammad; Kahliq,Abdul; Matloob,Amar; Nadeem Abbas,Rana; Mansoor Javaid,Muhammad.
Identification of weed species with allelopathic potential and characterization of their adverse effects against associated crops is required for better understanding of weed-crop interactions. Phytotoxic activity of Euphorbia dracunculoides Lam. on germination and seedling growth of chickpea (Cicer arietinum L.) and wheat (Triticum aestivum L.) was investigated under controlled conditions. Two separate studies were done with each of four organic solvent fractions (n-hexane, chloroform, ethylacetate, 1-butanol) and crude aqueous (1:10 and 1:20) whole plant fractions of E. dracunculoides using distilled water and 0.05% (v/v) dimethyl sulfoxide (DMSO) as control. Different aqueous and organic fractions of E. dracunculoides had a significant bearing on...
Tipo: Journal article
Palavras-chave: Allelopathy; Weeds; Germination attributes; Suppression; Phenolics.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400006

Evaluation of Low-Drift Nozzles in Agrochemical Applications in Orchards
Provedor de dados: 117
Autores: Behmer,Sergio; Di Prinzio,Alcides; Striebeck,Guillermina; Magdalena,Jorge.
Fruit production demands several phytosanitary treatments per year. The efficiency of these treatments is affected by product loss because of drift, a situation that is aggravated by frequent high winds and the presence of a substantial rural population. The objective of this study was to evaluate the distribution and to quantify product losses in fruit orchard applications. Fluorescent tracers with air-blast sprayers were applied, using air-induction hollow cone nozzles, compared to conventional hollow cone nozzles. To evaluate drift, pipes cleaner were placed on columns behind the adjacent row to the treated one, and for the losses under the tree, Petri dishes were located below the treated row; for the distribution in the tree, leaves were collected...
Tipo: Journal article
Palavras-chave: Orchards; Sprayers; Drift; Air-induction nozzles.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300017

A Dynamic Decision Support System for Farm Water Management in Surface Irrigation: Model Development and Application
Provedor de dados: 117
Autores: Flores,Carlos I.; Holzapfel,Eduardo A.; Lagos,Octavio.
An online dynamic decision support system (DDSS) was developed, to support the farm water management in surface irrigation. The online DDSS was based on the formulation and integration of three components: a dynamic-relational data base, an administrator model, and a graphical user interface. The DDSS allows routines of actualization, edition and addition of online data, providing information in real time. The online DDSS was applied in an orange orchard (Citrus sinensis L. Osbeck) cv. Valencia Late under furrow irrigation. The results pointed out that the time irrigation cutoff was the main significant management factor, to decrease the hazard of leaching, superficial runoff and percolation. Applying the results obtained with the DDSS, furrow irrigation...
Tipo: Journal article
Palavras-chave: Furrow irrigation; On-line irrigation management; Orange orchard.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200011

Antioxidant Capacity, Anthocyanins, and Total Phenols of Wild and Cultivated Berries in Chile
Provedor de dados: 117
Autores: Guerrero C,Jaime; Ciampi P,Luigi; Castilla C,Andrea; Medel S,Fernando; Schalchli S,Heidi; Hormazabal U,Emilio; Bensch T,Emma; Alberdi L,Miren.
It is possible to incorporate a lot of natural antioxidants into the human organism by consuming berries which can prevent diseases generated by the action of free radicals. Antioxidants neutralize free radicals and thus protect the organism from the oxidative damage of lipids, proteins, and nucleic acids. Berries stand out as one of the richest sources of antioxidant phytonutrients among various fruits and vegetables. The objective of this research was to determine antioxidant capacity (AC), total anthocyanins (TA), and total phenols (TP) of wild and cultivated berries in different localities of La Araucanía and Los Ríos Regions in Chile. These parameters were analyzed by using the free radical 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) method,...
Tipo: Journal article
Palavras-chave: ; 2-diphenyl-1-picrylhydrazyl antioxidant potential.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400002

Microencapsulation of maqui (Aristotelia chilensis Molina Stuntz) leaf extracts to preserve and control antioxidant properties
Provedor de dados: 117
Autores: Vidal J,Leslie; Avello L,Marcia; Loyola C,Cristina; Campos P,Jorge; Aqueveque M,Pedro; R. Dungan,Stephanie; Galotto L,Maria; Guarda M,Abel.
Microencapsulation technology is an alternative to stabilize stress factors and protect food ingredients or additives, which include environmentally sensitive bioactive principles in protective matrices to increase their functionality and life span. The objective of this research was to study conditions to obtain microcapsules with antioxidant capacity from a maqui (Aristotelia chilensis [Molina] Stuntz, Elaeocarpaceae) leaf extract by emulsification and subsequent retention after microencapsulation. Microcapsules were produced by water-in-oil emulsion (W/O) using a phase of the aqueous maqui leaf extract and gum arabic, and a liquid vaseline phase. Maqui leaf extract antioxidant capacity was 99.66% compared with the aqueous phase of the emulsion at 94.38...
Tipo: Journal article
Palavras-chave: Maqui; Antioxidant capacity; Bioactive compounds; Gum arabic.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100003

Molecular Tools for Rapid and Accurate Detection of Black Truffle (Tuber melanosporum Vitt.) in Inoculated Nursery Plants and Commercial Plantations in Chile
Provedor de dados: 117
Autores: Cordero,Cecilia; Cáceres,Pablo; González,Gloria; Quiroz,Karla; Carmen,Bravo; Ramírez,Ricardo; Caligari,Peter D.S; Carrasco,Basilio; García-Gonzales,Rolando.
Truffle (Tuber melanosporum Vitt.) culture is an agroforestry sector in Chile of increasing interest due to the high prices that truffles fetch in the national market and the recent evidence that its commercial production is possible in Chilean climatic and soil conditions. In this study, the efficiency of three methods of DNA extraction from a mix of 5 g of soil and roots from both nursery and field plants of Quercus ilex L. mycorrhized with T. melanosporum were evaluated, and a simple and reproducible protocol was established. Detection of T. melanosporum was performed by the technique of cleaved amplified polymorphic sequence (CAPS) from amplicons generated with the primers ADL1 (5´-GTAACGATAAAGGCCATCTATAGG-3´) and ADL3 (5´-CGTTTTTCCTGAACTCTTCATCAC-3`),...
Tipo: Journal article
Palavras-chave: Ectomycorrhizas; Molecular markers; PCR; CAPS; Ectomicorrizas; Marcadores moleculares; PCR; CAPS.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300022

Pecosa-Baer: A New Cultivar of New Cultivar Cultivar of White Lupin with Determined Bushy Growth Habit, Sweet Grain and High Protein Content
Provedor de dados: 117
Autores: von Baer,Erik; von Baer,Ingrid; Riegel,Ricardo.
The expansion of white lupin (Lupinus albus L.) cultivation in Chile is subject to the availability of cultivars presenting high yield potential, tolerance to the main fungal diseases and homogeneous ripening. In response to these requirements, a new cultivar has been developed and registered as ‘Liapec-&gt;1’, commercially registered as ‘Pecosa-Baer’. This new cultivar has determined bushy growth habit. Its flowering period is concentrated in approximately 40 days, less than the 77 days of cv. Rumbo-Baer. This trait allows it to reach harvest without heterogeneity problems. The seed is speckled, flat and medium-sized (370 g/1000 grains aprox.). The kernels are sweet and have a high protein content of around 41% (dry matter basis). In field assays,...
Tipo: Journal article
Palavras-chave: Cultivar.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400013

Use of Enzymatic Biosensors as Quality Indices: A Synopsis of Present and Future Trends in The Food Industry
Provedor de dados: 117
Autores: Serna Cock,Liliana; Zetty Arenas,Ana María; Ayala Aponte,Alfredo.
Biosensors are an important alternative in the food industry to ensure the quality and safety of products and process controls with effective, fast and economical methods. Their technology is based on a specific biological recognition element in combination with a transducer for signal processing. The use of enzymatic biosensor technology in food processing, quality control and on-line processes is promising compared to conventional analytical techniques, as it offers great advantages due to size, cost, specificity, fast response, precision and sensitivity. This article reviews the development and use of some enzyme biosensors in the food industry, describes the most important application areas and analyzes the current situation and future possibilities....
Tipo: Journal article
Palavras-chave: Biosensors; Enzymes; Analysis in food; Safety; Quality; Control processes.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200017

Soil Management and Efficiency of Rhizobia Strains of Cowpea Vigna unguiculata (L.) Walp. in the Tropics
Provedor de dados: 117
Autores: Donizetti dos Santos,José Geraldo; Ferreira Aguiar,Alana das Chagas; Silva Junior,Edilson Máximo; Lemes Dadalto,Danubia; Rodrigues Sousa,Merijane; Ribeiro Xavier,Gustavo; Gomes de Moura,Emanoel.
In the humid tropics, the largest obstacle to the implementation of sustainable farming systems is the reduced efficiency of nutrient use by crops. This study assesses the effectiveness of five selected rhizobia strains in symbiosis with cowpea (Vigna unguiculata (L.) Walp.), with the objective of replacing N fertilization in the predominant agricultural system used by smallholder farmers. The study was carried out in three adjacent areas with distinct agricultural uses: conventional tillage, itinerant agriculture, and a no-till system. The experimental design was in randomized complete blocks with four replicates and seven treatments: five rhizobia strains (BR3262, BR3267, BR3299, INPA3-11B, and UFLA 3-84) and two controls without inoculation (one without...
Tipo: Journal article
Palavras-chave: Agroecosystem; Nitrogen-fixing nodule bacteria; Legumes.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400015

Effect of Arbuscular Mycorrhizal Fungi Glomus spp. Inoculation on Alfalfa Growth in Soils with Copper
Provedor de dados: 117
Autores: Novoa M,Daniela; Palma S,Soledad; Gaete O,Hernán.
Soils near mining centers usually have high heavy metal (HM) levels. It has been found that some plants associated with arbuscular mycorrhizal fungi (AMF) improve growth and tolerance to HM in soils. This symbiosis is a biological resource for degraded soil recovery. The objective of this study was to determine the effect of inoculating AMF (Glomus spp.) on alfalfa (Medicago sativa L.) growth in agricultural soils with different copper (Cu) levels for degraded soil recovery. To this effect, alfalfa seeds were grown in soils from the Catemu and Casablanca valleys and inoculated with AMF. Plant height, stem diameter, and number of leaves were measured weekly. Dry matter, mycorrhizal colonization, and Cu concentration in alfalfa plant tissues were measured...
Tipo: Journal article
Palavras-chave: Mycorrhizal colonization; Soil recovery.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200009

Influence of Conservation Tillage and Soil Water Content on Crop Yield in Dryland Compacted Alfisol of Central Chile
Provedor de dados: 117
Autores: Martinez G,Ingrid; Ovalle,Carlos; Del Pozo,Alejandro; Uribe,Hamil; Valderrama V,Natalia; Prat,Christian; Sandoval,Marco; Fernández,Fernando; Zagal,Erick.
Chilean dryland areas of the Mediterranean climate region are characterized by highly degraded and compacted soils, which require the use of conservation tillage systems to mitigate water erosion as well as to improve soil water storage. An oat (Avena sativa L. cv. Supernova-INIA) - wheat (Triticum aestivum L. cv. Pandora-INIA) crop rotation was established under the following conservation systems: no tillage (Nt), Nt + contour plowing (Nt+Cp), Nt + barrier hedge (Nt+Bh), and Nt + subsoiling (Nt+Sb), compared to conventional tillage (Ct) to evaluate their influence on soil water content (SWC) in the profile (10 to 110 cm depth), the soil compaction and their interaction with the crop yield. Experimental plots were established in 2007 and lasted 3 yr till...
Tipo: Journal article
Palavras-chave: Neutron probe; Penetrometer resistance; Oat; Subsoiling; Water erosion; Wheat.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400018

Differences in the Detoxification Metabolism between Two clonal Lineages of the Aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) Reared on Tobacco (Nicotiana tabacum L.)
Provedor de dados: 117
Autores: Cabrera-Brandt,Marco A; Fuentes-Contreras,Eduardo; Figueroa,Christian C.
Myzus persicae (Sulzer) is a highly polyphagous aphid species, with a subspecies (M. persicae nicotianae) well adapted to tobacco (Nicotiana tabacum L.). We evaluated the effect of this host plant on the aphid performance and detoxification enzymes, in order to test the participation of xenobiotic metabolism on the ability of this aphid to overcome the tobacco chemical defences. Two genotypes, one corresponding to the only M. persicae nicotianae genotype reported in Chile on tobacco, and one genotype belonging to M. persicae sensu stricto were reared on tobacco and pepper (Capsicum annuum L.), respectively. M. persicae nicotianae showed a significantly higher intrinsic rate of increase (r m) on pepper than on tobacco, and M. persicae s.s. performed...
Tipo: Journal article
Palavras-chave: Detoxification enzymes; Esterases; Glutathione S-transferases; Monooxygenases; Intrinsic rate of increase.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400006

Inhibiton of Yellow Nutsedge (Cyperus esculentus L.) and Bermudagrass (Cynodon dactylon (L.) Pers) by a Mulch Derived from Rye (Secale cereale L.) in grapevines
Provedor de dados: 117
Autores: Ormeño-Núñez,Juan; Pino-Rojas,Gerardo  ; Garfe-Vergara,Farouk.
Two field trials (Los Andes 1998-1999 and Santiago 2004-2005) were carried out to determine growth inhibition of yellow nutsedge (Cyperus esculentus L.) and bermudagrass (Cynodon dactylon (L.) Pers.), growing on the plantation row, by mulch derived from a rye (Secale cereale L.) cover crop established between grapevine (Vitis vinifera L.) rows on overhead (cv. Flame Seedless) and vertical (cv. Cabernet Sauvignon) training. Spring mowing of the rye sown in the fall allowed for developing a thick and long lasting mulch along the grape rows. Nutsedge and bermudagrass control was 81 and 82%, respectively, and was more effective than conventional chemical (in the row) + mechanical (between rows) control. Glyphosate at 2% for nutsedge and 1% for bermudagrass...
Tipo: Journal article
Palavras-chave: Mulch; Cover crop; Rye; Grapevines.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300003

Use of Laccase-Producing Microorganisms in Membrane Systems for Polluting Agents Removal: Consideration and Perspectives
Provedor de dados: 117
Autores: Serna C,Liliana; Cuesta A,Fernando L.
Contamination is defined as the presence of pollution agents in an ecosystem reaching an abnormal concentration level and causing adverse effects. Due to the important environmental problems that these cause in the food chain, diverse methods have been formulated to minimize those effects; among these enzymatic methods associated to microorganisms or other biological agents are used, and systems that allow to metabolize pollutants in an effective and practical way. The combined use of these systems appears to be the most appropriated option to eliminate pollution agents at a reasonable energy cost which allows their use in the industry. The present review identifies the adequate process conditions for technological implementation of biofilm-type membrane...
Tipo: Journal article
Palavras-chave: Laccase; Biofilm; Membrane system; Halogen compound.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400010

Bioactivity of Tepa (Laureliopsis philippiana (Looser) Shodde) Powder to Sitophilus zeamais Motschulsky Control in Laboratory
Provedor de dados: 117
Autores: Ortiz U,Ana; Silva A,Gonzalo; Urbina P,Angélica; Zapata S.M,Nelson; Rodríguez M,J. Concepción; Lagunes T,Angel.
The maize weevil (Sitophilus zeamais Motschulsky) is one of the most widespread pests and causes heavy losses of stored grain throughout the world. Control of this insect is primarily dependent upon continued applications of organophosphorus and pyrethroid insecticides and fumigants as phosphine but the increasing problems with current insecticides drive the need for research and to develop new control methods. The insecticidal effect of leaf powder of tepa, Laureliopsis philippiana (Looser) Shodde, was evaluated against maize weevil under laboratory conditions. The parameters evaluated were adult mortality and emergence, grain weight loss and germination, and residual, repellent and fumigant effect. The highest levels of insect mortality were registered...
Tipo: Journal article
Palavras-chave: Stored grains; Botanical insecticides; Maize weevil.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100011

Hessian Fly, Mayetiola destructor (Say), Populations in the North of Tunisia: Virulence, Yield Loss Assessment and Phenological Data
Provedor de dados: 117
Autores: Makni,Hanem; Bouktila,Dhia; Mezghani,Maha; Makni,Mohamed.
Hessian fly, Mayetiola destructor (Say), is a destructive pest of wheat worldwide and an endemic pest in Tunisia. Two natural populations of this insect from the North of Tunisia were evaluated, in the field, for their virulence, based on response developed by bread wheat (Triticum aestivum L.) cultivars carrying H3, H5, H6, H7H8, H11, H13 and H16 resistance genes. H11, H13 and H16 showed a high effectiveness against both populations; therefore, their implication in Hessian fly breeding programs would be of interest. The level of infestation, as well as the yield loss, was assessed, based on the percentage of infested plants and variation in growth parameters due to infestation. The percentage of infested plants, over a 2-yr period in Mateur, averaged...
Tipo: Journal article
Palavras-chave: Wheat; Biotype; Generations; Integrated pest management.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300009

Evaluation of fertilization with uncoated urea and 3,4-dimethylpyrazole phosphate (DMPP)-coated urea on nitrogen leaching and rose (Rosa spp.) yield
Provedor de dados: 117
Autores: García-Castro,Alexandra; Restrepo-Díaz,Hermann.
The negative impact of N over-fertilization has acquired importance in rose (Rosa spp.) growers in Colombia. The nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) has been considered a valuable alternative to diminish the N losses by leaching and to enable more efficient N use efficiency in crops. The objective of the present work was to study the effect of DMPP on the mineral N (NH4+- N and NO3--N) content in soil and water leaching, and physiological characteristics of rose plants. A greenhouse experiment was performed for 10 wk. Four-year-old 'Charlotte' rose cultivars grafted on 'Natal Briar' were grown in soil and fertirrigated daily with a complete nutrient solution containing 170 mg N L-1. Two N fertilizers (uncoated urea [UA], and urea...
Tipo: Journal article
Palavras-chave: Chlorophyll fluorescence; Leaf nitrogen concentration; Nitrate leaching; Nitrogen use efficiency.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200011

Effect of Arbucula Myrrhizal Fungi on an Ecological Crop of Chili Peppers (Capsicum annuum L.)
Provedor de dados: 117
Autores: Castillo R,Claudia ; Sotomayor S,Leonardo ; Ortiz O,César; Leonelli C,Gina; Borie B,Fernando; Rubio H,Rosa.
Mapuche farmers in southern Chile have been cultivating local ecotypes of chili pepper (Capsicum annuum L.), called locally “Cacho de cabra” for many decades. It is used to make “merkén”, a condiment that is consumed locally and exported. This vegetable requires a nursery stage and can obtain nutritional benefits from symbiotic associations such as mycorrhizal fungi, achieving a better adaptation to transplanting. Arbuscular mycorrhizal fungi (AMF) are obligate biotrophes appearing in abundance in agroecosystems with conservation management. The aim of this study was to compare effectiveness of two AMF, a commercial mycorrhizal inoculant (IC, Glomus intraradices) and another native (IN, Glomus claroideum) with a control without inoculation (-I) on the...
Tipo: Journal article
Palavras-chave: Mycorrhiza; Inoculant; Biofertilizers; Fruit quality; Vegetables.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100010

Insecticidal Efficacy of Azadirachta indica, Nucleopolyhedrovirus and Chlorantraniliprole Singly or Combined against Field Populations fo Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)
Provedor de dados: 117
Autores: Wakil,Waqas; Usman Ghazanfar,M; Nasir,Fozia; Abdul Qayyum,Mirza; Tahir,Muhammad.
The development of resistance in cosmopolitan insect Helicoverpa armigera Hubner (Lepidoptera: Noctuidae) forced the researchers for alternative control measures. In the present study, insecticidal efficacy of formulations of Azadirachta indica, a Nucleopolyhedrovirus (NPV), and new anthranilic diamide insecticide (chlorantraniliprole) formulations was determined against 2nd, through 5th larval instars of H. armigera collected from diverse geographical locations in the Punjab province, Pakistan. Azadirachta indica was applied at 5 &amp;#956;L L-1; NPV at 2.1 x 10(5) polyhedral occlusion bodies (POB) mL4 and chlorantraniliprole at 0.01 &amp;#956;L L-1, either alone or in combinations with each other. The bioassays were conducted at 27 ± 1 °C and 65 ± 5%...
Tipo: Journal article
Palavras-chave: NPV; Chlorantraniliprole; Additive; Populations.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100009

Effects of Fungicides on the Development of the Entomopathogenic Fungus Metarhizium anisopliae var. anisopliae
Provedor de dados: 117
Autores: Yáñez,Maribel; France,Andrés.
Metarhizium anisopliae (Metschnikoff) Sorokin is an entomopathogenic fungus used for controlling different insect pests. It is most frequently applied to berry fruit crops, where fungicides are also used for disease control. Fungicides: azoxystrobin, benomyl, captan, chlorothalonil, fenhexamid, fludioxonil, iprodione, and metalaxyl in concentrations of 0.01, 0.1, 1.0, 10, and 100 mg L-1 were evaluated in this research study. Vegetative growth, conidia germination, and conidia germination tube length were measured on the Qu-M82, Qu-M151b, Qu-M253, Qu-M430, and Qu-M984 Metarhizium anisopliae var. anisopliae fungus strains. Those strains were selected because of their present use against different insect pest in bramble fruits. Vegetative growth was measured...
Tipo: Journal article
Palavras-chave: Biological control; Integrated management; Fungal growth; Conidia germination.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300006

Herbage Production, Nutritive Value and Grazing Preference of Diploid and Tetraploid Perennial Ryegrass Cultivars (Lolium perenne L.)
Provedor de dados: 117
Autores: Balocchi,Oscar A; López,Ignacio F.
The objective of this study was to determine, under the soil and climatic conditions of Southern Chile, the effect of the ploidy of perennial ryegrass (Lolium perenne L.) cultivars on herbage production, nutritive value, grazing preference and utilization of pasture produced. This study was conducted in southern Chile, Valdivia Province, and was evaluated for 3 years. The tetraploid cultivars used were Quartet (4n), Gwendal (4n), Pastoral (4n) and Napoleon (4n). The diploid cultivars were Anita (2n), Jumbo (2n), Aries (2n), and Yatsyn 1 (2n).When the average sward height reached 20 cm, all plots were simultaneously grazed by dairy cows for a period of 24 h. Before and after grazing, sward height, dry matter availability and nutritive value were evaluated....
Tipo: Journal article
Palavras-chave: Grazing preference; Herbage mass; Ploidy.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300005

Mating behavior of the predator Podisus nigrispinus (Heteroptera: Pentatomidae) under exposure to neem: Comportamiento de apareamiento del depredador Podisus nigrispinus (Heteroptera: Pentatomidae) expuesto al neem
Provedor de dados: 117
Autores: Domingues de Oliveira,Sharrine Omari; Faria Barbosa,Wagner; Vilca Malqui,Karina Soledad; Carvalho Guedes,Raul Narciso.
The preservation of natural enemies is one of the basic foundations for integrated pest management. Botanical insecticides have shown low impact on beneficial arthropods in relation to survival. Insecticides studies usually focus on the direct physiological effects of insecticides, whereas relatively little attention is placed on the behavioral response to exposure. A study was conducted to evaluate the effect of the botanical insecticide neem (Azadirachta indica A. Juss.; Meliaceae) on the mating behavior of the predatory stinkbug Podisus nigrispinus (Heteroptera: Pentatomidae). Unmated 5 to 7 d-old adults, separate by sex, were exposed to azadirachtin per contact on the treated surface. The treatments were composed for: untreated male and female;...
Tipo: Journal article
Palavras-chave: Azadirachtin; Azadirachta indica; Biological insecticide; Natural enemy.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400010

Physiological Dose-Response of Coffee (Coffea arabica L.) Plants to Glyphosate Depends on Growth Stage
Provedor de dados: 117
Autores: de Carvalho,Leonardo Bianco; Aguiar Alves,Pedro Luis da Costa; Bianco,Silvano; De Prado,Rafael.
Glyphosate is the main herbicide used in coffee (Coffea arabica L.) plantations in Brazil. Problems with herbicide drift commonly occur in orchard fields due to non-adequate spraying conditions. A series of experiments was carried out aiming to evaluate physiological dose-response of C. arabica plants submitted to exposure to simulated glyphosate drift in two distinct plant growth stages. Glyphosate was applied at 0, 180, 360, and 720 g acid equivalent (AE) ha-1 directly on coffee plants with 10 and 45 d after transplanting (DAT). Glyphosate doses in a range of 180-360 g AE ha-1 increased photosynthesis, transpiration and stomatal conductance in 10 DAT-plants up to 14 d after application (DAA) while, in 45 DAT-plants, an increase was observed only up to 2...
Tipo: Journal article
Palavras-chave: N-(phosphonomethyl) glycine; Herbicide drift; Photosynthesis; Plant nutrition.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200003

Evaluation of Metarhizium anisopliae var. anisopliae Qu-M845 Isolate to Control Varroa destructor (Acari: Varroidae) in Laboratory and Field Trials
Provedor de dados: 117
Autores: Rodríguez,Marta; Gerding,Marcos; France,Andrés; Ceballos,Ricardo.
The effectiveness of the Metarhizium anisopliae (Metschinkoff) Qu-M845 isolate was evaluated in laboratory and field trials. It was previously selected for thermal resistance (at 30 and 35 ºC) and pathogenicity on Varroa destructor (Anderson and Trueman). In the laboratory, the first evaluations were carried out by spraying and increasing the concentration from zero to 10(8) conidia mL-1 on varroa adults. Lethal concentrations required for 50 and 90% mite mortality (LC50 and LC90) were 3.8 x 10(5) and 8 x 10(7) conidia mL-1, respectively (&amp;#967;2 = 2.03). In the autumn field trials, three application methods (doses of 5 x 10(10) conidia per hive) were evaluated. The treatments were: a) conidia stamped on filter paper, located on every second frame...
Tipo: Journal article
Palavras-chave: Biological control; Entomopathogenic fungi; Varroasis; Insect pathology.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400009

Implementation of a Method to Determine Lolitrem-B in Ryegrass (Lolium perenne L.) by Liquid Chromatography (HPLC)
Provedor de dados: 117
Autores: Moyano A,Stella; Lanuza,Francisco; Torres B,Alfredo; Cisternas A,Ernesto; Fuentes V,Marcela.
Lolitrem-B is a neurotoxic substance that causes the ryegrass staggers syndrome in cattle, sheep, and horses consuming ryegrass (Lolium perenne L.) infected with endophytic fungus Neotyphodium lolii (Latch, Christensen, and Samuels) Glenn, Bacon, and Hanlin. Due to the increasing use of ryegrass pasture in southern Chile, it is necessary to know the content of lolitrem-B to optimize grazing management and reduce the effect on animal health. The objective of this study was to implement a method to determine lolitrem-B in ryegrass. Ryegrass samples were used without the endophyte, freeze-dried, and kept in darkness at -18 ºC to establish the method. Then, a pure lolitrem-B standard was added and the toxin was extracted with a mixture of chloroform-methanol...
Tipo: Journal article
Palavras-chave: Mycotoxin; Neurotoxin; Endophyte fungi.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300019

Phosphate Fertilization Can Increase Yield of Productive Grass Pea (Lathyrus sativus L.) Crops in P-Retentive Soils
Provedor de dados: 117
Autores: Montenegro,Adolfo; Mera,Mario.
The effect of P fertilization on grass pea (Lathyrus sativus L.) yield and yield components was evaluated on soils with low P availability and high P retention capacity in small-scale farms of the Araucanía Region in southern Chile. Trials were conducted during 2000-2001, 2001-2002, and 2002-2003, in six sites; three sites in Lumaco and three in the Selva Oscura area. Six rates of P (0, 21.8, 43.6, 65.4, 87.2, and 109.0 kg ha-1) were evaluated in a randomized complete block design with four replicates. Grass pea cv. Luanco-INIA was sown at 47 seeds m-2. Mean grain yield for all trials was 2456 kg ha-1. Phosphate fertilization increased grass pea grain yield in both areas during 2000 and 2001. There was no significant effect in 2002. The 2002 cropping...
Tipo: Journal article
Palavras-chave: Grass pea; Phosphorus; Neglected crops; Cool-season legumes.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200014

In Field Assessment on the Relationship between Photosynthetic Active Radiation (PAR) and Global Solar Radiation Transmittance through Discontinuous Canopies
Provedor de dados: 117
Autores: Oyarzún,Ricardo; Stöckle,Claudio; Wu,Joan; Whiting,Matthew.
In many crop models, the process of radiation transmittance through the canopy is normally described as an exponential attenuation process (Beer’s Law equation), which is assumed to be valid for canopies covering the ground with a random spatial distribution of leaves. However, for discontinuous canopies, where a distinctive row pattern of plant exists, there is a more complex situation because of the presence of gaps between individual plants. This must be accounted for when characterizing radiation relationships for these kinds of systems, in particular when short time-scales are of interest. Photosynthetically active radiation (PAR) transmittance (&amp;#964;PAR) is more commonly studied and reported than global solar radiation (Sg) transmittance...
Tipo: Journal article
Palavras-chave: Radiation interception; Extinction coefficient; Crop simulation model.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100015

Genetic Parameters and Predictive Genetic Gain in Maize with Modified Recurrent Selection Method
Provedor de dados: 117
Autores: Afonso Doná,Anderson; Vieira Miranda,Glauco; Oliveira DeLima,Rodrigo; Gonçalves Chaves,Luciana; Gomes e Gama,Elto Eugênio.
The modified recurrent selection method suggests a less productive population to test the other population more productive and itself aiming to have more genetic gains than tradition recurrent selection method that uses one population to test the other one. The objectives of this work were to estimate the genetic components, to predict and to evaluate the genetic gains of the SynFlint and Syndent populations of maize (Zea mays L.), applying a modified recurrent selection method. Two recombination cycles were carried out, with 144 Si progeny per cycle. These progenies were test crossed with SynFlint, generating a SynFlint x Syndent inter-population and a SynFlint x SynFlint intra-population. The progenies were evaluated in five environments in the first...
Tipo: Journal article
Palavras-chave: Breeding methods; Genetic variability.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100006

Evaluation of Perennial Forage Legumes and Herbs in Six Mediterranean Environments
Provedor de dados: 117
Autores: Real,Daniel; Li,Guangdi D; Clark,Steve; Albertsen,Tony O; Hayes,Richard C; Denton,Matt D; D’Antuono,Mario F; Dear,B.S.
There is an absence of drought tolerant herbaceous perennial forage legume and herb options other than lucerne (Medicago sativa L.) for environments with Mediterranean-like climates common in extensive areas of Southern Australia, the Mediterranean basin, and Chile. Therefore, a collection of 174 forage perennial legume and herb entries from 103 species and 32 genera was evaluated for adaptation in a diverse range of Mediterranean climatic environments in Southern Australia. The seasonal rainfall distribution varied from moderately to highly winter dominant with long term average annual rainfall ranging from 318 to 655 mm. The entries were rated for productivity and persistence over 3 yr. The 12 entries identified as the most promising for winter, summer,...
Tipo: Journal article
Palavras-chave: Herbage yield; Legume persistence; Australian native germplasm.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300003

Selection of Entomopathogenic Fungi to Control Varroa destructor (Acari: Varroidae)
Provedor de dados: 117
Autores: Rodríguez,Marta; Gerding,Marcos; France,Andrés.
The aim of this work was select entomopathogenic fungi tolerant to temperatures inside the brood area of honey bees (Apis mellifera) for to control Varroa destructor. For this purpose, 50 Beauveria bassiana (Balsamo) Vuillemin and 48 Metarhizium anisopliae (Metschn.) Sorokin isolates were evaluated at 30 and 35 ºC. For each isolate, colony discs of 5 mm with mycelium were placed in the center of a Petri dish with Sabouraud dextrose agar (SDA) medium. The dishes were incubated at 30 and 35 °C, without light. Radial growth of each colony was measured daily. All the B. bassiana and M. anisopliae isolates presented a lineal growth rate at a temperature of 30 ºC. However, at 35 ºC, most of the isolates did not grow, except three B. bassiana and 14 M. anisopliae...
Tipo: Journal article
Palavras-chave: Biological control; Entomopathogenic fungi; Varroasis; Entomopathology.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400008

Modelling Supplementation Strategies for Beef Steer Rearing and Fattening Systems in Southern Chile
Provedor de dados: 117
Autores: Toro,Paula; Catrileo,Adrián; Aguilar,Claudio; Vera,Raúl.
A mathematical model was developed to analyze beef production systems in Southern Chile. The study considered the identification of the main components of systems under different beef steer management strategies, using pasture with or without supplementation and back grounding cattle on pasture followed by a winter period of confined feeding with pasture silage and concentrates. Validation of model outputs using 200 kg LW Hereford steers against real experimental data showed no significant differences (P &amp;#8805; 0.01) between simulated and observed final weights. In order to analyze the interaction between the stocking rate (SR) and supplementation, three SR of 2, 2.5 and 3 steers ha-1 with and without pasture silage supplementation at the rate of 5 kg...
Tipo: Journal article
Palavras-chave: Beef cattle; Supplementation; Grazing systems; Simulation models.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200010

Increased Growth and Changes in Wheat Mineral Composition through Calcium Silicate Fertilization under Normal and Saline Field Conditions
Provedor de dados: 117
Autores: Anser,Ali; Basra,Shahzad M.A; Hussain,Safdar; Iqbal,Javaid.
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Tipo: Journal article
Palavras-chave: Salt stress; Silicon; Wheat growth; K+:Na+; Water potential; Stomatal conductance.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100016

Response of Productive and Morphovegetative Traits of Globe Artichoke (Cynara cardunculus var. scolymus) to Mass Selection and Estimation of their Heritability
Provedor de dados: 117
Autores: Martin,Eugenia; Cravero,Vanina; Liberatti,David; Espósito,Andrea; López Anido,Fernando; Cointry,Enrique.
There have been few reports on genetic parameters or artificial selection for growth traits in globe artichoke (Cynara cardunculus var. scolymus), the study of the effect of one cycle of mass selection and realized heritability estimates would be valuable for planning breeding strategies in this species. A C0 segregating population was formed from the cross of two contrasting seed-grown cultivars, Imperial Star and Estrella del Sur FCA. Selected plants for productive traits were intercrossed to produce a C1 population. The C1 population along with the C0 population, both parents and the F1 were evaluated obtaining the response to selection and estimating realized heritability. Mass selection for increased yield and precocity was particularly successful,...
Tipo: Journal article
Palavras-chave: Additive actions; Breeding program; Realized heritability.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200002

Residual Effect of Pesticides used in Integrated Apple Production on Chrysoperlaexterna (Hagen) (Neuroptera: Chrysopidae) Larvae
Provedor de dados: 117
Autores: Moura,Alexandre P; Carvalho,Geraldo A; Botton,Marcos.
Temperate fruit crops are an important economic activity for growers in southern Brazil. However, several pest species are associated to apple (Malus domestica Borkh.) crops in Brazil. Pesticides are largely used to control them and one way to change this is to combine selective pesticides and predator insects. The goal of this research was to evaluate the effects of the abamectin, carbaryl, fenitrothion, methidathion, sulfur, and trichlorfon pesticides on the survival and stage length of larvae and pupae, adult oviposition from treated larvae, and hatched eggs of two Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) populations. The compounds were sprayed on glass plates in accordance with the International Organization for Biological Control...
Tipo: Journal article
Palavras-chave: Green lacewings; Insecticides; Natural enemies; Pest control; Side effects.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200009

Effect of nitrogen on achene protein, oil, fatty acid profile, and yield of sunflower hybrids
Provedor de dados: 117
Autores: Ali,Amjed; Ullah,Sami.
Seed yield and achene oil yield are the main determinants for N application rates rather than seed composition. Nitrogen plays a critical role in producing unsaturated fatty acids (oleic and linoleic acids), which are the main factors determining sunflower oil quality (Helianthus annuus L.). Studies were conducted on the effect of N fertilization on seed yield, achene oil yield, and quality parameters of sunflower hybrids for two successive years (2010 and 2011) in a split plot arrangement under a randomized complete block design. The hybrids (Hysun-33 &amp;amp; S-278) and N levels (0, 75, 150, and 225 kg ha-1) were allotted in main and sub-plots, respectively. Increasing N levels resulted in steady increases in yield, protein contents and linoleic acid,...
Tipo: Journal article
Palavras-chave: Fertilization; Linoleic acid; Oleic acid; Palmitic acid; Helianthus annuus.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400016

In situ Rumen Degradation Kinetics of High-Protein Forage Crops in Temperate Climates
Provedor de dados: 117
Autores: Valderrama L.,Ximena; Anrique G.,René.
The present study was conducted to evaluate the nutritional value and in situ degradation kinetics of eight high protein forage crops: alfalfa (Medicago sativa L.), forage oat (Avena sativa L.), mixed pasture, and ryegrass (Lolium multiflorum Lam.) pasture in early vegetative stages, two forage lupins (Lupinus albus L.) in early bloom stages, sugar beet (Beta vulgaris L.) and kale (Brassica napus var. pabularia (DC.) Rchb.) leaves at root maturity. Dry matter (DM) and crude protein (CP) degradation kinetics were evaluated by the nylon bag technique through the in situ procedure described by 0rskov and MacDonald (1979) using three ruminally cannulated sheep. Chemical composition of the forage crops showed on average 13.7% DM; 21.4% CP; 31.5% neutral...
Tipo: Journal article
Palavras-chave: Rumen; Forage; Rate of passage; Chemical composition; Degradability.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400012

Evaluating the use of Atriplex nummularia Hay on Feed Intake, Growth, and Carcass Characteristics of Creole Kids
Provedor de dados: 117
Autores: Meneses,Raúl; Varela,Gabriel; Flores,Hugo.
There is a surplus of Atriplex nummularia Lindl. grazing that can be used as animal feed. This material was harvested to assess the effects on intake, growth, and carcass characteristics of kids. Atriplex replaced alfalfa hay (Medicago sativa L.) in a proportion of 0%, 10%, 20%, 30%, and 40% for 60 creole kids weighing 13 kg and was assigned to the diets in a completely randomized design. The process was conducted from March to May. Two males and two females were used from each group to evaluate individual nutrient intake. Height at withers, thoracic diameter, and weight change were evaluated in all the animals. The carcasses of four females per group were evaluated. Offered and rejected hay diet samples were chemically analyzed. Atriplex hay crude protein...
Tipo: Journal article
Palavras-chave: Goats; Hay.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100012

Comparison of Root Induction in Mature Filbert (Corylus avellana L.) Explants by Agrobacterium Rhizogenes and Indolbutiric Acid
Provedor de dados: 117
Autores: Sánchez-Olate,Manuel; Sáez,Patricia; Cartes,Priscila; Alvarez,Carolina; Ríos,Darcy.
From in vitro cultured adult material of Corylus avellana L. cv. Negretta, adventitious rooting of microshoots was evaluated. Rhizogenic induction mediated by two strains of wild-type Agrobacterium rhizogenes (A477 and A478) and indolbutyric acid (IBA) were compared under two light conditions (16:8 h photoperiod and complete darkness). The results indicate that in the 16:8 h photoperiod induction, the rooting rate with IBA (90%) was significantly higher than that obtained with the strain A477 of A. rhizogenes (67.7%), while with the strain A478 no statistically significant difference was obtained for the same variable (75%). On the other hand, under complete darkness, rooting mediated by IBA (90%) significantly surpassed the results obtained with both...
Tipo: Journal article
Palavras-chave: Rooting; European hazelnut.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100013

Using Irrigation Scheduling to Increase Water Productivity of Wheat-Maize Rotation under Climate Change Conditions
Provedor de dados: 117
Autores: El Afandi,Gamal; Khalil,Fouad A; Ouda,Samiha A.
Irrigation scheduling was used to increase water productivity of wheat (Triticum aestivum L.)-maize (Zea mays L.) rotation under two climate change scenarios. Three wheat varieties and two maize hybrids were planted at in a 2-yr field experiment. CropSyst model was calibrated and validated for the collected field data, then was used to assess the impact of two climate change scenarios (A2 and B2) and three adaptation strategies (early sowing changing, irrigation schedule and the interaction between them) in the year of 2038s. The results revealed that A2 reduced yield more than B2 scenario for both crops. High yield reduction in wheat-maize rotation could be expected under climate change conditions, where wheat and maize yield will be reduced by an average...
Tipo: Journal article
Palavras-chave: Pan evaporation technique; CropSyst; HadCM3; Climate change scenarios; Adaptation strategies; Evaporación de bandeja; CropSyst; HadCM3; Escenarios de cambio climático; Estrategias de adaptación.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300015

Cocoa Bean (Theobroma cacao L.)Drying Kinetics
Provedor de dados: 117
Autores: MacManus Chinenye,Ndukwu; Ogunlowo,A.S; Olukunle,O.J.
Cocoa (Theobroma cacao L.) is widely produced in West Africa and South America and is a great economic tree crop, with so many industrial uses. In this work, the experimental drying kinetics of foreign species was investigated, and the experiments were carried out under isothermal conditions, using heated batch drier at 55, 70 and 81 ºC. The moisture ratio data obtained from change of moisture content with the drying time was fit to two thin layer drying model with good results. A faster drying process was observed at a higher drying temperature resulting in higher drying rates which is advantageous when evaluating costs. Fick’s second law of diffusion was used to predict effective diffusivity using experimental data assuming that the variation of...
Tipo: Journal article
Palavras-chave: Moisture content; Drying temperature; Diffusivity; Moisture ratio; Equilibrium moisture content.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400014

Effect of Ethephon on Almond Bloom Delay, Yield, and Nut Quality under Warm Climate Conditions in Northwestern Mexico
Provedor de dados: 117
Autores: Grijalva-Contreras,Raúl Leonel; Martínez-Díaz,Gerardo; Macías-Duarte,Rubén; Robles-Contreras,Fabián.
World almond (Prunus dulcis (Mill.) D.A. Webb) production is mostly located in areas where flowering is injured by low temperatures, and using ethephon (2-chloroethylphosphonic acid) to delay bloom is suggested as a measure to avoid frost damage. However, it is unknown if that practice could be beneficial in Mexico’s warm climates. The objective of this study was to determine the effect of ethephon on almond bloom delay and yield. We evaluated foliar applications of ethephon at doses of 75, 150, and 300 mg L-1 at 10% leaf drop stage and at 150 mg L-1 during dormancy over 2 yr. In 2004, ethephon applied at 10% leaf drop stage delayed bloom by 7, 8, and 9 d at 75, 150, and 300 mg L-1, respectively (p &lt; 0.01), and in 2005, bloom delay was 3 d at 300 mg...
Tipo: Journal article
Palavras-chave: Frost damage; Ethephon; Yield; Nut quality.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100004

Antioxidant Capacity and Total Phenolic Compounds of Twelve Selected Potato Landrace Clones Grown in Southern Chile
Provedor de dados: 117
Autores: Ah-Hen,Kong; Fuenzalida,Carolina; Hess,Susan; Contreras,Andrés; Vega-Gálvez,Antonio; Lemus-Mondaca,Roberto.
Colored potatoes (Solanum tuberosum L.) provide a natural source of phytochemicals that help reduce the risk of diseases. However, there is a lack of information on the degree of variation of the antioxidant activity and polyphenolic contents of these native potatoes. Thus, the antioxidant activity (AA) and total phenolic content (TPC) of native Chilean potatoes were determined. Twelve potato landrace clones collected from established cultivations on Chiloe Island and Valdivia were selected. Total phenolic content and AA were compared with two commercial varieties, Shepody and Desirée. Total phenolic content was determined by the Folin-Ciocalteu method, and &amp;#946;-carotene bleaching was used to compare AA. The TPC varied in the peeled potato samples...
Tipo: Journal article
Palavras-chave: Chilean potatoes antioxidant activity total phenolics Folin-Ciocalteu &amp;#946; -carotene.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100001

Residual Glycerol from Biodiesel Manufacturing, Waste or Potential Source of Bioenergy: A Review
Provedor de dados: 117
This review provides a summary of the research conducted on the use of crude glycerol, the major byproduct of the biodiesel industry, as substrate for anaerobic co-digestion and production of biogas. In general, for every 100 kg biodiesel produced, approximately 10 kg crude glycerol is generated. Because this glycerol is expensive to purify for use in food, pharmaceutical, or cosmetic industries, biodiesel producers must seek alternative methods for its disposal. Several studies have demonstrated that the use of crude glycerol as a C source for fermentation and biogas generation is a promising alternative use for this waste material. The high C content of glycerol increases the C:N ratio in the mixture, avoiding the inhibition of the process by the excess...
Tipo: Journal article
Palavras-chave: Anaerobic co-digestion; Glycerol; Biogas; Biodiesel; Digestate.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300019

Hosting Capacity of Horticultural Plants for Insect Pests in Brazil
Provedor de dados: 117
Autores: Leite,Germano L.D; Picanço,Marcelo; Zanuncio,José C; Moreira,Márcio D; Jham,Gulab N.
Factors such as fertilization, allelochemicals, trichomes, weather, and natural enemies can influence pest populations. Thus, it is necessary to understand the factors that predispose vegetable species to pests and the role of polyculture, crop rotation, and neighboring plants. The objective of this research was to study the hosting capacity for pests of Abelmoschus esculentus (L.), Brassica oleracea L. vars. acephala and capitata, Capsicum annuum L., Cucurbita moschata (Duchesne), Cucurbita maxima Duchesne and Cucumis sativus L., Lycopersicon esculentum Mill., Solanum gilo Raddi and Solanum melongena L., and Phaseolus vulgaris L. The higher density of Bemisia tabaci (Genn.) adults on C. sativus can be due to the higher amount of pentacosane and octacosane...
Tipo: Journal article
Palavras-chave: Trichomes; Allelochemicals; Nitrogen; Potassium; Insects.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300006

Fatty Acid Composition of Longissimus dorsi Muscle of Suffolk Down Lambs Fed on Different Dryland Forages
Provedor de dados: 117
Autores: Gallardo,María Asunción; Pulido,Rubén; Gallo,Carmen.
Sheep production on dryland is based on natural pasture. The aim of this study was to evaluate the effect of dryland legume pastures on the fatty acid composition of lamb meat. The study included 21 Suffolk Down male lambs aged about 2-mo that were randomly assigned to three types of pastures: successional pasture, subterranean clover/Wimmera ryegrass (Trifolium subterraneum L./Lolium rigidum Gaudin), or red clover/Wimmera ryegrass (T.pratense L./L. rigidum) for 66 d, and slaughtered after. The fatty acid profile measured in the Longissimus dorsi muscle showed no significant differences as to the content of saturated (SFA), polyunsaturated fatty acids (PUFA), and the omega6/omega3 rate (co6/co3). There was a trend (p &gt; 0.06) towards a higher...
Tipo: Journal article
Palavras-chave: Lamb meat; Muscle fat; Legume pastures.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400011

Kipa-INIA, new high yield spring bread wheat variety for Chile
Provedor de dados: 117
Autores: Matus,Iván; Madariaga,Ricardo; Jobet,Claudio; Zúñiga,Javier; Alfaro,Christian.
Kipa-INIA is a spring wheat variety (Triticum aestivum L.) originated from a cross carried out in the Wheat Plant Breeding Project of the Instituto de Investigaciones Agropecuarias (INIA), in the Centro Regional de Investigación Quilamapu (36°31’ S; 71°54’ W) in 1993. It has an upright growth habit in the seedling stage. The adult plant is low to medium height and varies between 90 and 95 cm. The spike is white with long awns along its full length. The grain is ovate, white, and vitreous. It was sown in mid-August in the Santa Rosa Experimental Field, Chillán, head emergence occurred 90 to 95 d after sowing, i.e. is 4 to 6 d before ‘Domo-INIA’. On the mean, ‘Kipa-INIA’ sown under irrigation conditions reached a yield of 11.7% higher than the control var....
Tipo: Journal article
Palavras-chave: Spring wheat; New cultivar; Kipa-INIA.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200018

Litter Decomposition of Acacia caven (Molina) Molina and Lolium multiflorum Lam. in Mediterranean Climate Ecosystems
Provedor de dados: 117
Autores: Martínez G,Ingrid; Zagal V,Erick; Ovalle M,Carlos; Coûteaux,Marie-Madeleine; Stolpe,Neal B; Valderrama V,Natalia.
The ecosystems of the Mediterranean interior dryland of Chile, dominated by an espinal agroecosystem of Acacia caven (Molina) Molina, show low productivity as a result of soil degradation. The objective of this study was to evaluate litter decomposition of A. caven and Lolium multiflorum Lam. in espinal ecosystems: well preserved (Wp) 50 to 80%, typical (Pd) 25 to 50%, and degraded (De) with 10 to 25% cover. During 420 d and starting in April 2004 until August 2005, weight loss in litter bags and chemical composition (hemicellulose, cellulose, lignin, non-structural components, ash, N, C, C/N ratio, and P) were determined by using near infrared reflectance spectroscopy (NIRS) and the Van Soest protocol. Weight loss ranged from 31 to 52% in L. multiflorum...
Tipo: Journal article
Palavras-chave: Canopy cover; Weight loss; Litter bags; NIRS; Principal components.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300013

Effect of Vermicompost and Compost on Lettuce Production
Provedor de dados: 117
Autores: Hernández,Adriana; Castillo,Hugo; Ojeda,Dámaris; Arras,Ana; López,Julio; Sánchez,Esteban.
A greenhouse study was conducted to evaluate the effect on total growth and leaf nutritional content in lettuce (Lactuca sativa L.) in the Agrotechnology Sciences Department of the Universidad Autonoma de Chihuahua, Mexico in 2007. Three types of fertilization treatments were analyzed: two organic and one conventional or inorganic. Both vermicompost and compost were produced from cattle manure in a 25-wk process. The study included 12 experimental units made up of lettuce plantlets var. Great Lakes. A linear model was fitted for statistical analysis using a completely randomized experimental design. ANOVA was performed and means were compared by orthogonal contrasts. Results showed differences in weight and leaf content for the N and K variables, and the...
Tipo: Journal article
Palavras-chave: Fertilization; Nutrient; Growth; Quality.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400008

Adaptation and Genotype x Environment Interaction of Flaxseed (Linum usitatissimum L.) Genotypes in South Central Chile
Provedor de dados: 117
Autores: Berti,Marisol; Fischer,Susana; Wilckens,Rosemarie; Hevia,Felicitas; Johnson,Burton.
Flaxseed (Linum usitatissimum L.) is imported into Chile mostly for bread making and feed. Identification of genotypes best adapted for seed production in South Central Chile would facilitate producer’s decision. The objective of this study was to determine the adaptation and genotype x environment interaction of 16 flaxseed genotypes (including 10 from North American and six from Argentine sources) grown at 11 environments (defined as location-year) in Chile from 2003 to 2007. Genotype seed yield was above 5700 kg ha-1 for some environments indicating a high yield potential. According to the AMMI (Additive Main Effects and Multiplicative Interaction) and SREG (Sites regression) models the 11 environments were classified into four groups by the AMMI and...
Tipo: Journal article
Palavras-chave: Adaptation; Genotype; Seed yield; Oil content; Linolenic acid.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300001

Insecticidal Activity of Peumus boldus Molina Essential Oil against Sitophilus zeamais Motschulsky
Provedor de dados: 117
Autores: Betancur R,Jessica; Silva A,Gonzalo; Rodríguez M,J. Concepción; Fischer G,Susana; Zapata S.M,Nelson.
In stored grains, the main agents diminishing production are insects, which can produce losses between 20% and 80% before harvest or under storage. The insecticidal properties of the essential oil of fresh leaves of Peumus boldus Molina against maize weevil (Sitophilus zeamais Motschulsky) adults were determined under laboratory conditions. The highest mortality (100%) was achieved at 4% concentration by contact with a treated glass surface. The same concentration in impregnated corn (Zea mays L.) grain, resulted in 98.7% mortality. Mortality by fumigant action at 6 h was 100% with 35 µL oil in 0.15 L (air volume). Concentrations 1, 2 and 4% of essential oil produced 0% F1 adult emergence. At 10 d of residual effect, the 4% concentration reached 63.7%...
Tipo: Journal article
Palavras-chave: Maize weevil; Boldus; Stored grains; Botanical insecticides.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300007

Location and Classification of Moving Fruits in Real Time with a Single Color Camera
Provedor de dados: 117
Autores: Reyes,José F; Chiang,Luciano E.
Quality control of fruits to satisfy increasingly competitive food markets requires the implementation of automatic servovisual systems in fruit processing operations to cope with market challenges. A new and fast method for identifying and classifying moving fruits by processing single color images from a static camera in real time was developed and tested. Two algorithms were combined to classify and track moving fruits on image plane using representative color features. The method allows classifying the fruit by color segmentation and estimating its position on the image plane, which provides a reliable algorithm to be implemented in robotic manipulation of fruits. To evaluate the methodology an experimental real time system simulating a conveyor belt...
Tipo: Journal article
Palavras-chave: Fruit classification; Color image feature; Servo visual control; Look-and-move.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200007

Onset of the Rainy Season in the Province of Córdoba (Argentina) Determined by Rainfall Records and Evaluation of its Agricultural Risk Condition
Provedor de dados: 117
Autores: de la Casa,Antonio.
Knowing more precisely the onset of the rainy season in a region would reduce risk at crop establishment. To evaluate this issue, the study proposes a simple procedure based only on daily rainfall data to estimate the onset of the wet season, by analyzing records of seven meteorological stations in the Province of Córdoba between the years 1961 and 2006. The onset of the rainy season was defined according to the simultaneous occurrence of two conditions: (i) the amount of rainfall in 3 consecutive days equal to or greater than 20 or 30 mm, (ii) a period without rain of 7 to 16 d during the subsequent 30-d period. Onset of the rainy season shows strong interannual variability throughout the region. An increase from 20 to 30 mm of rain in 3 successive days...
Tipo: Journal article
Palavras-chave: Onset of rainy season; Risk of implantation; Bivariate normal distribution.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400012

Adoption of Bt Cotton: Threats and Challenges
Provedor de dados: 117
Autores: Faisal Bilal,Muhammad; Farrukh Saleem,Muhammad; Ashfaq Wahid,Muhammad; Shakeel,Amir; Maqbool,Mudassar.
Adopting new technology always involves advantages and risks; Bt cotton (Gossypium hirsutum L.) is a new technology well known in developed countries for its many advantages, such as reduced pesticide application, better insect pest control, and higher lint yield. However, its success in developing countries is still a question mark. Global adoption of Bt cotton has risen dramatically from 0.76 million ha when introduced in 1996 to 7.85 million ha in the 2005 cotton-growing season where 54% of the cotton crops in the USA, 76% in China, and 80% in Australia were grown with single or multiple Bt genes. Bollworms are serious cotton pests causing 30-40% yield reduction in Pakistan and 20-66% potential crop losses in India. The major advances shown in this...
Tipo: Journal article
Palavras-chave: Bt cotton; Management; Gossypium hirsutum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300017

Analysis of Agromorphological Descriptors to Differentiate between Duke Cherry (Prunus x gondouinii (Poit. &amp;amp; Turpin)Rehd.) and Its Progenitors: Sweet Cherry (Prunus avium L.) and Sour Cherry (Prunus cerasus L.)
Provedor de dados: 117
Autores: Pérez,Rodrigo; Navarro,Florentino; Sánchez,María Ángeles; Ortíz,Jesús María; Morales,Remedios.
The rapid identification of the hybrids between sweet cherry (Prunus avium L.) and sour cherry (Prunus cerasus L.) is not easy. In order to resolve this problem, 18 Spanish sweet, sour and duke cherry cultivars were surveyed and characterized using 43 agromorphological descriptors evaluated in flowers, leaves, dormant 1-yr-old shoots, fruits, and trees during 2005 and 2006. Based on quantitative parameters, ANOVA and stepwise discriminant analysis (SDA) were carried out. For qualitative descriptors, statistical comparisons were done by means of the chi-square (&amp;#967;2) test. As result of the study, two quantitative (titratable acidity and number of lenticels) and six qualitative descriptors (shape of the central and lateral lobes in the internal bracts...
Tipo: Journal article
Palavras-chave: Rosaceae; Characterization; Quantitative parameters; Qualitative parameters; SDA analysis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100004

Determination of Antioxidant Capacity, Total Phenolic Content and Mineral Composition of Different Fruit Tissue of Five Apple Cultivars Grown in Chile
Provedor de dados: 117
Autores: Henríquez,Carolina; Almonacid,Sergio; Chiffelle,Italo; Valenzuela,Tania; Araya,Manuel; Cabezas,Lorena; Simpson,Ricardo; Speisky,Hernán.
Apples (Malus domestica Borkh.) have been identified as one of the main dietary sources of antioxidants, mainly phenolic compounds. These compounds vary in their composition and concentration, among cultivars and fruit tissues. In this research, the total phenolic content (Folin-Ciocalteau assay), antioxidant capacity (Ferric Reducing Antioxidant Power, FRAP assay) and mineral composition in three fruit tissues (peel, pulp and whole fruit), of apple cultivars commonly used for dried apple production in Chile, were studied. In addition, the physical-chemical characteristics (dry weight, pH, titratable acidity, soluble solids content and color) were also evaluated. The results indicated that the total phenolic content, the antioxidant capacity, and the...
Tipo: Journal article
Palavras-chave: Folin-Ciocalteau assay; FRAP antioxidant capacity; Physical-chemical parameters.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400001

Biological Activity of Essential Oils from Leaves and Fruits of Pepper Tree (Schinus molle L.) to Control Rice Weevil (Sitophilus oryzae L.)
Provedor de dados: 117
Autores: Benzi,Verónica; Stefanazzi,Natalia; Ferrero,Adriana A.
Rice weevil (Sitophilus oryzae L.) is a primary insect pest of stored grain. The development of resistance resulted in the application of synthetic insecticides. In recent years many plant essential oils have provided potential alternatives to currently used insect control agents. The Brazilian pepper tree (Schinus molle L. var. areira (L.) DC.) (Anacardiaceae) has different biological properties such as insecticidal activity. In this study, repellent, fumigant activity, nutritional indices, and feeding deterrent action were evaluated on S. oryzae adults. Filter paper impregnation was used to test fumigant toxicity, whereas treated whole wheat was used to evaluate repellent activity and a flour disk bioassay was done to evaluate feeding deterrent action...
Tipo: Journal article
Palavras-chave: Repellency; Fumigant toxicity; Nutritional indices; Feeding deterrence.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200004

Sugarcane Molasse and Whey as Additives in the Silage of Lemongrass (Cymbopogon citratus [DC.] Stapf) Leaves
Provedor de dados: 117
Autores: Ventura-Canseco,Lucía María Cristina; Mendoza Nunez,José Alfredo; Abud-Archila,Miguel; Oliva-Llaven,Maria Ángela; Dendooven,Luc; Gutiérrez-Miceli,Federico A.
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Tipo: Journal article
Palavras-chave: Silage quality; Response surface methodology; PH; Lactic acid.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100014

Nutritional Strategies to Improve Nitrogen use Efficiency by Grazing Dairy Cows
Provedor de dados: 117
Autores: Keim,Juan Pablo; Anrique,René.
Grazing dairy cows are characterized by converting a low proportion of dietary N into milk N. This low N use efficiency (NUE) is mainly due to an excessive supply of crude protein (CP) of pasture with regard to animal requirements. Excess N in the diet has negative effects for the animal; it alters the organoleptic characteristics of milk and pollutes the environment through N excretions. The aim of this review was to analyze the available information on nutritional strategies to improve NUE by grazing dairy cows, such as diluting the dietary N through supplementation, synchronizing ruminal carbohydrate (CHO), and N fermentation rates, and using pastures with a high water soluble carbohydrates (WSC) content. There is a beneficial effect of carbohydrate...
Tipo: Journal article
Palavras-chave: Concentrate supplementation; Ruminal synchrony; High sugar ryegrass; Crude protein; Milk production.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400019

Bayesian Analysis of the Genetic Control of Survival in F3 Families of Common Bean
Provedor de dados: 117
Autores: Mora,Freddy; Gonçalves-Vidigal,Maria C; Santos,Alexandra I.
The objectives of this study were to examine the genetic control of survival in segregant families F3 of the common bean (Phaseolus vulgaris L.) in southern Brazil during the 2004-2005 growing season, to identify useful genotypes for the breeding program of this crop, and to determine the genetic association between survival and weight of 100 seeds (production trait; P100). A Bayesian approach was used to predict breeding values and to estimate variance components. Survival was recorded as a binary response: dead plant or live plant during harvest. The total population consisted of 11,520 individual plants. The difference in the magnitude between the best and the worst families was as high as 22%, and varied from 57 to 73%. Survival was found to be highly...
Tipo: Journal article
Palavras-chave: Genetic improvement; Breeding; Gibbs algorithm; Heritability.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400003

Sensitivity of Venturia inaequalis Chilean Isolates to Difenoconazole, Fenarimol, Mancozeb, and Pyrimethanil
Provedor de dados: 117
Autores: Henríquez S,Jose Luis; Sarmiento V,Oliver; Alarcón C,Paula.
Apple scab (Venturia inaequalis) is the most important disease in Chilean apple (Malus domestica Borkh.) orchards where fungicide management is the main tool to control disease. Sensitivity tests to difenoconazole, fenarimol, mancozeb, and pyrimethanil fungicides were conducted on V. inaequalis wild isolates to construct local baseline sensitivity distributions, and compare them with a collection of isolates from seven different commercial orchards with no evidence of practical resistance. In vitro assays were conducted and sensitivity was measured as inhibition of mycelial growth (difenoconazole, fenarimol, pyrimethanil) or conidial germination (mancozeb). Departure from the baseline distribution to less sensitivity was found for difenoconazole,...
Tipo: Journal article
Palavras-chave: Apple; Apple scab; Fungicides; DMI fungicides; Dithiocarbamates; Anilinopyrimidines.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100005

Prediction of the Chemical Composition and Fermentation Parameters of Pasture Silage by Near Infrered Reflectance Spectroscopy (NIRS)
Provedor de dados: 117
Autores: Ibáñez,Lorena; Alomar,Daniel.
The capability of near infrared reflectance spectroscopy (NIRS) was evaluated to predict the content of total ash (TA), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF) and metabolizable energy (ME); as well as pH and ammonia nitrogen content (N-NH3), in pasture silage, with and without additives. Nine hundred and twenty dried and ground samples of pasture silage, with known chemical composition, were scanned over the visible and NIR region (400 to 2500 nm) at 2 nm intervals. Calibration equations were developed by modified partial least square regression models (MPLS) with different mathematical treatments and light scatter correction as standard normal variation and Detrend (SNV &amp;amp; D) of the spectra....
Tipo: Journal article
Palavras-chave: Nutritional composition; Silage; Pasture; Spectroscopy; NIRS.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400005

Influence of planting methods on root development, crop productivity and water use efficiency in maize hybrids
Provedor de dados: 117
Autores: B. Khan,Muhammad; Yousaf,Farhan; Hussain,Mubshar; W. Haq,Muhammad; Lee,Dong-J; Farooq,Muhammad.
Optimum planting methods better ensure water and nutrient supply through improved root development resulting in better crop growth and productivity. This study was conducted to evaluate the effects of planting methods on root development, crop allometry, water use efficiency (WUE), productivity and economic returns of different maize (Zea mays L.) hybrids. Maize hybrids NK-6621, Pioneer-30Y87, and Pioneer-30Y58 were sown on beds, ridges, and flat surface. Ridge sowing was better followed by bed sowing; while amongst the hybrids, 'Pioneer-30Y87' performed the best. Well-developed root system, with longer primary root, more number of lateral roots and higher root growth rate, was observed in 'Pioneer-30Y87' planted on ridges, which led to higher WUE, grain...
Tipo: Journal article
Palavras-chave: Allometry; Planting methods; Root growth rate; Water use efficiency.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400015

Genotype × Environment Interaction in Canola (Brassica napus L.) Seed Yield in Chile
Provedor de dados: 117
Autores: Escobar,Magaly; Berti,Marisol; Matus,Iván; Tapia,Maritza; Johnson,Burton.
Genotype x environment (G × E) interaction in canola (Brassica napus L.) cultivar seed yield is unknown in Chile. The interaction was performed with the SREG (Sites Regression) model. Two experiments were conducted in five and thirteen environments in the 2008-2009 season in Central South Chile. The experimental design was a randomized complete block (RCBD) in each environment with four replicates and 26 open-pollinated or hybrid canola genotypes in Experiment 1, and RCBD with three replicates and 17 genotypes in Experiment 2. ANOVA was used to determine the significance of the G × E interaction. biplots were used to graphically interpret and determine the best cultivar in each environment and the corresponding mega-environments. The G × E interaction was...
Tipo: Journal article
Palavras-chave: SREG; GGE; MET; Interaction; Biomass.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200001

The Effect of using Quail Litter Biochar on Soybean (Glycine max L. Merr.) Production
Provedor de dados: 117
Autores: Suppadit,Tawadchai; Phumkokrak,Nittaya; Poungsuk,Pakkapong.
Biochars can be used as soil amendments for improving soil properties and crop yield. The objective of this research was to study the plant growth, yield, yield components, and seed quality, including nutrients and heavy metals (Pb, Cd, and Hg), in the soybean plant (Glycine max L. Merr.) and soil. The experiment was conducted from September 2010 to January 2011 in a greenhouse located in the Dan Khun Thot District, Nakhon Ratchasima Province, Thailand. The research comprised six treatments with four replicates in a completely randomized design. Quail litter biochar (QLB) at rates of 0, 24.6, 49.2, 73.8, 98.4 and 123 g per pot mixture were provided to soybean cv. Chiang Mai 60. The results showed that QLB could be used as a soil fertility improvement and...
Tipo: Journal article
Palavras-chave: Crop yield; Element; Nutrient uptake; Pyrolysis; Soil fertility.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200013

Photosensitivity of Cucumber (Cucumis sativus L.) Seedlings Exposed to Ultraviolet-B Radiation
Provedor de dados: 117
Autores: Tapia F,María Luisa; Toro A,Guillermo  ; Parra R,Bélgica  ; Riquelme E,Alejandro.
The intensity of ultraviolet-B radiation (UV-B) has increased on the Earth´s surface due to the stratospheric ozone depletion, causing an adverse effect on a wide range of species, such as morphological, physiological, and biochemical alterations. This research studied the intraspecific photosensitivity of cucumber (Cucumis sativus L.) seedlings exposed to UV-B. Six commercial cultivars were evaluated: Laura, Sprint 440, Dasher II, Exocet, Poinsett 76, and Marketmore 76 under greenhouse-controlled environmental conditions with a hydroponic sandwich-type system with a Hoagland II nutrient solution. Seedlings were irradiated from expanded cotyledons to the third true leaf with three intensities of UV-B radiation (30, 40, and 50 &amp;#956;W cm-2) for 18 d...
Tipo: Journal article
Palavras-chave: UV radiation; Chlorophyll; UV-B absorbing compounds; Chlorosis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100002

Pepsin-Cellulase Digestibility of Pasture Silages: Effects of Pasture Type, Maturity Stage, and Variations in the Enzymatic Method
Provedor de dados: 117
Autores: Barchiesi-Ferrari,Claudia; Alomar,Daniel; Miranda,Horacio.
Enzymatic in vitro digestibility has been studied as a method to predict energy values of forages for ruminants, although results have been affected by type of forage and methodological details of the technique. This work was performed to evaluate the effects of cellulase concentration (0.75, 1.0 and 6.25 g L-1), incubation time (24 or 48 h) and type of final washing of the residue (water or acetone) on the in vitro digestibility of the dry matter (DMD), organic matter (OMD) and content of digestible organic matter in the DM (D value) of silages made at three maturity stages from three types of pastures: a) permanent pasture (Dactylis glomerata, Lolium perenne, Bromus catharticus Vahl var. catharticus, Trifolium repens and Holcus lanatus); b) Italian...
Tipo: Journal article
Palavras-chave: Cellulase incubation; Enzymatic digestibility; In vitro digestibility.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200010

Management of Auxin-Cytokinin Interactions to Improve Micropropagation Protocol of Henequen (Agave fourcroydes Lem.)
Provedor de dados: 117
Autores: Garriga Caraballo,Miguel; González Oramas,Gerardo; Alemán García,Silvia; Abreu Cruz,Enildo; Quiroz Bravo,Karla; D.S. Caligari,Peter; García-González,Rolando.
Henequen (Agave fourcroydes Lem.) is a high value plant species both for agricultural and ecological uses. The species is very well known worldwide by the quality of its fiber that is widely used for industrial purposes. This species is propagated at a large scale by asexual methods but current propagation technologies are not satisfying the grower’s demands. A. fourcroydes has been cultivated n vitro but it has shown some recalcitrant behaviour during the multiplication and rooting stages. The combination of 6-benzylamynopurine (BAP) (0.75 mg L-1) and indolebutyric acid (IBA) (1.0 mg L-1) instead of 2,4-dichlorophenoxyacetic acid (2,4-D) significantly improved explant survival and shooting during the establishment of n vitro young shoots. Combining...
Tipo: Journal article
Palavras-chave: Propagation; Thidiazuron; 6-benzylamynopurine; In vitro culture.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400003

Non-Target Effects of Dalaca pallens Blanchard Control Examined Through Principal Response Curves: A Guild Approach in Southern Chile
Provedor de dados: 117
Autores: Devotto,Luis; Cisternas,Ernesto; Carrillo,Roberto; Gerding,Marcos.
The non-target effects of biological control are a complex matter requiring a multi-approach analysis. A fungal biopesticide is under research to control the larval stages of the ghost moth Dalaca pallens Blanchard (Lepidoptera: Hepialidae) in southern Chile. A field experiment was conducted to compare the effects of the biological control agent Beauveria bassiana (Balsamo) Vuillemin (10(12) spores ha-1) and the insecticide lambda-cyhalothrin (7.5 g active ingredient ha-1) on non-target invertebrate species belonging to different guilds. The soil invertebrates were collected by using pitfall trapping and soil coring before and after spraying the biocontrol agent or the insecticide. Caught individuals were assigned to predator, herbivore or decomposer...
Tipo: Journal article
Palavras-chave: Ghost moth; Entomopathogen; Biopesticide; Lepidoptera; Hepialidae.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300002

Effect of Nitrogen Rates and Split Nitrogen Fertilization on Grain Yield and its Components in Flooded Rice
Provedor de dados: 117
Autores: Hirzel,Juan; Pedreros,Alberto; Cordero,Karla.
Nutritional management in rice (Oryza sativa L.) crops is mainly associated with N fertilization, which is difficult to adjust in field conditions due to variations in soil type and climatic conditions. Between 28 000 and 46 000 ha per year is dedicated to rice production in Chile and profits depend on fertilization. A field experiment determine the effect of N rates and split N fertilization on grain yield and its components was carried out in two locations during two consecutive seasons (2007 to 2009), where five N rates and five split N fertilizations were evaluated. The locations were in Parral (36º2’ S; 72º08’ W, Vertisol) and San Carlos (36º19’ S; 71º59’ W, Inceptisol), with N rates of 80, 100, 120, 140, and 160 kg ha-1 applied in different...
Tipo: Journal article
Palavras-chave: Irrigated rice; Nitrogen management; Rice productivity.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300015

Potential of Spectral Reflectance as Postharvest Classification Tool for Flower Development of Calla Lily (Zantedeschia aethiopica (L.) Spreng.)
Provedor de dados: 117
Autores: . Steidle Neto,Antonio J; Grossi,José A.S; Lopes,Daniela C; Anastácio,Enrique A.
Unsuitable postharvest management is one of the most serious problems that floriculture has to face. An option for reducing postharvest losses is to use automatic systems for flower sorting and classification, which yield consistent results, reduce costs and speed up these tasks. The objective of this work was show the potential of spectral reflectance to distinguish different postharvest development stages of calla lily flowers, Zantedeschia aethiopica (L.) Spreng., aiming the use of this technology within automatic systems for flower classification. The measuring equipment was a spectrometer connected to a portable computer and configured for reflectance data acquisition in the 400 to 1000 nm range. Based on the results, it was verified a differentiation...
Tipo: Journal article
Palavras-chave: Cut flowers; Spectrometer.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400015

Characterization of Volatile Compounds in the Essential Oil of Sweet Lime (Citrus limetta Risso)
Provedor de dados: 117
Autores: Colecio-Juárez,Maria C; Rubio-Núnez,Rubria E; Botello-Álvarez,José E; Martinez-González,Gloria M; Navarrete-Bolanos,José L; Jiménez-Islas,Hugo.
The essential oil of citrus fruit contains components pleasant sensory characteristics that are appreciated in food, pharmaceutical, and cosmetics industries. In the case of sweet lime (Citrus limetta Risso), is necessary to characterize the essential oil components, to identify potential uses of this fruit. The essential oil of sweet lime was obtained from lime flavedo in four different maturation stages. Steam distillation was employed and then compared with hexane extraction. The identification of the components in the essential oil was carried out by gas chromatography and mass spectrometry. A total of 46 components were found in the essence of lime, among which the highest concentration of compounds present were aldehydes such as limonene. Linalool,...
Tipo: Journal article
Palavras-chave: Sweet lime; Essential oil; Steam distillation; Maturation stages.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200017

Gene Expression Analysis: A Way to Study Tolerance to Abiotic Stresses in Crops Species
Provedor de dados: 117
Autores: Pérez-Torres,Eduardo; Paredes C,Mario; Polanco,Víctor; Becerra B,Viviana.
Regions traditionally destined to agriculture report an ever increasing exposure to cold and drought conditions. This is especially important in countries like Chile where crop management options are limited. The development of new cultivars with better yields under adverse conditions is fundamental if the ever increasing demand for food is to be matched; however, improving tolerance to abiotic stresses has proved to be a complex task. In this regard, development in plant physiology and genomics in the last 20 years has led to a deeper understanding of how plants respond to stress and mechanisms responsible for different ranges of tolerance observed in nature. This review discusses the techniques currently most in use in gene expression analysis, together...
Tipo: Journal article
Palavras-chave: Cold; Drought; Crops species; Gene expression.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200016

Determination of Quality Chemical Parameters of Honey from Chubut (Argentinean Patagonia)
Provedor de dados: 117
Autores: Aloisi,Pia Valeria.
This study was intended to evaluate the quality chemical parameters of 62 Apis mellifera L. honey samples, from the Province of Chubut, Argentine. Samples were obtained from the three melliferous areas of this province: Andean region, lower Chubut River valley and plains of Senguerr River. The average values obtained for electrical conductivity (0.33 mS cm-1) and pH (4.17) indicate that the analyzed honeys came mainly from nectar. Electrical conductivity was higher in honeys from the Andean region than in honeys from the other two regions. Moisture (water content) was low, with an average value of 14.67%. The hydroxymethylfurfural (HMF) content was very low and ranged between 0.0 and 14.70 mg kg-1. Moisture, HMF and free acidity values show good maturity...
Tipo: Journal article
Palavras-chave: Honey characterization; Argentinean honeys; Patagonian honeys; Quality parameters.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400015

Toxicity of Field-Aged Permethrin-Loaded Attracticides on Choristoneura rosaceana (HARRIS) and Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae) Adult Males and Females
Provedor de dados: 117
Autores: Curkovic,Tomislav; Brunner,Jay F; J. Brown,John.
Lethal and sub lethal effects were evaluated in the laboratory on Choristoneura rosaceana (Harris) and Pandemis pyrusana Kearfott males exposed to an attracticide loaded with permethrin and aged in the field. The effect of pairing conspecific females with previously intoxicated males was also evaluated. In both species a significantly greater mortality of male moths (&amp;#8805; 95%) was observed 24 h after exposure to t he attracticide formulation. Likewise, high levels of knock down (&amp;#8805; 75%) were observed in males of both species 1 h after attracticide exposure. In females, knock down was &amp;#8805; 2.5% and mortality &amp;#8805; 3.3% after pairing with intoxicated males. Leg autotomy in males was at least 73% in C. rosaceana and &amp;#8805;...
Tipo: Journal article
Palavras-chave: Bioassay; Fecundity; Fertility; Knockdown; Leg autotomy; Lethal effects; Mortality; Sub lethal effects.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100003

Influence of Vessel Type, Physical State of Medium and Temporary Immersion on the Micropropagation of Three Rhodophiala species
Provedor de dados: 117
Autores: Muñoz,Manuel; Seemann,Peter; Jara,Gloria; Riegel,Ricardo.
Rhodophiala C. Presl (Amaryllidaceae) is a genus of attractive flowering geophytes native to South America. They have ornamental value, but most species are little known and have conservation problems. The objective of this study was to optimize a micropropagation process to support the use and preservation of three Chilean native species, R. montana (Phil.) Traub, R. splendens (Rengifo) Traub., and R. ananuca (Phil.) Traub. The research evaluated the feasibility of implementing liquid medium culture and assessed the influence of different tissue culture systems on the shoot production and biomass increment of small bulbs. Three experiments were carried out. The first one determined the influences of flask size and volume of media; the second compared...
Tipo: Journal article
Palavras-chave: TIS; Liquid culture; Micropropagation; Acclimatization.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400014

Interference Interactions of Two Species of Echinochloa Genus with Rice
Provedor de dados: 117
Autores: Aminpanah,Hashem; Sharifi,Peyman; Firouzi,Saeed.
The aim of this study was to evaluate the relative competitive ability of barnyardgrass (BYG, Echinochloa crus-galli (L.) P. Beauv.) compared to rice barnyardgrass (ECPH, E. oryzicola (Vasinger) Vasinger) against rice (Oryza sativa L.) cv. Hashemi in a replacement series study. Experiment was arranged in randomized complete block design with three replicates using a factorial treatment arrangement. Factors were two species of Echinochloa genus (BYG and ECPH) and five rice:BYG or rice:ECPH mixture proportions (8:0, 6:2, 4:4, 2:6, and 0:8). Relative yield total of aboveground dry weight, root dry weight and leaf area indicated that BYG or ECPH were competing for the same resources with 'Hashemi'. In general, replacement series curves and relative crowding...
Tipo: Journal article
Palavras-chave: Echinochloa crus-galli; Competitiveness; Interference; Oryza sativa; Echinochloa oryzicola.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300010

Survival and Reproduction of Podisus nigrispinus (Heteroptera: Pentatomidae): Effects of Prey Scarcity and Plant Feeding
Provedor de dados: 117
Autores: Holtz,Anderson Mathias; Dias de Almeida,Gustavo; Matiello Fadini,Marcos Antonio; Salazar Zanuncio-Junior,José; Vinha Zanuncio,Teresinha; Cola Zanuncio,José.
The spined soldier bug Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) is a generalist predator that can alternatively feed on plant tissue to survive under prey scarcity. This research aimed to evaluate the effects of plant feeding forced by a shortage of prey on the survival and reproduction of P. nigrispinus on Eucalyptus urophylla S.T. Blake (Myrtaceae) plants in the field. Podisus nigrispinus adults were enclosed on branches of eucalyptus by using gauze bags. These adults were fed daily with Tenebrio molitor pupae (T1) or after 5 (T2), 10 (T3) or 15 (T4) days from mating to simulate prey shortage. The pre-oviposition period, number of egg masses, number and viability of eggs and longevity of females were evaluated. Females of P. nigrispinus...
Tipo: Journal article
Palavras-chave: Phytophagy; Biological control; Predator; Asopinae.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300021

Grain Quality, Nutrient use Efficiency, and Bioeconomics of Maize under Different Sowing Methods and NPK Levels
Provedor de dados: 117
Autores: Rehman,Abdul; Farrukh Saleem,M; Ehsan Safdar,Muhammad; Hussain,Safdar; Akhtar,Naeem.
Finding more efficient ways to fertilize crops will reduce N losses and increase nutrient uptake. A field experiment was conducted at the Agronomic Research Farm, University of Agriculture, Faisalabad, Pakistan, during 2006 and repeated in 2007. The crop was planted in three different geometrical arrangements, viz. flat sowing (rows spaced 75 cm), ridge sowing (ridges spaced 75 cm), and strip planting (double row strips spaced 120 cm with 30 cm between rows in a strip); NPK was applied in four different combinations (0-0-0 control, 200-100-100 low dose,250-125-125 medium dose, and 300-150-150 high dose kg ha-1). Both fertilizer use efficiency (FUE) and N use efficiency (NUE) were significantly lower with the high fertilizer dose (300-150-150 kg NPK ha-1)...
Tipo: Journal article
Palavras-chave: Nutrient; NPK; Efficiency; Economics; Planting methods; Maize.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400014

Chemical Constituents and Toxicity of Essential Oils of Oriental Arborvitae, Platycladus orientalis (L.) Franco, against Three Stored-Product Beetles
Provedor de dados: 117
Autores: Mehdi Hashemi,Seyed; Ali Safavi,Seyed.
Plant secondary metabolites play an important role in plant-insect interactions and therefore such compounds may have insecticidal or biological activity against insects. Fumigant toxicity of essential oils of leaves and fruits from oriental arborvitae (Platycladus orientalis (L.) Franco) (Cupressaceae) was investigated against adults of cowpea weevil (Callosobruchus maculatus Fab.), rice weevil (Sitophilus oryzae L.), and red flour beetle (Tribolium castaneum Herbst). Fresh leaves and fruits were subjected to hydrodistillation using a Clevenger-type apparatus and the chemical composition of the volatile oils was studied by gas chromatography-mass spectrometry (GC-MS). Twenty-six compounds (92.9%) and 23 constituents (97.8%) were identified in the leaf and...
Tipo: Journal article
Palavras-chave: Botanical insecticides; Fumigation; Stored-product insects.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200004

Symptom severity and viral protein or RNA accumulation in lettuce affected by big-vein disease
Provedor de dados: 117
Autores: Araya,Carolina; Peña,Elizabeth; Salazar,Erika; Román,Lisset; Medina,Claudia; Mora,Roxana; Aljaro,Agustín; Rosales,Inés-Marlene.
Big-vein disease (BVD) is a widespread and economically damaging disease in lettuce (Lactuca sativa L.). Typical symptoms are chlorotic clearing around leaf veins, leaf deformations, and impaired head development. In this research, we studied the relationship between symptom intensity and protein and viral RNA accumulation in infected plants. Naturally infected lettuce plants, from the field or greenhouse, were classified according to their symptomatology: mild, moderate, severe, and symptomless. Coat protein accumulation was evaluated by a double antibody sandwich/enzyme-linked immunosorbent assay (DAS-ELISA), and RNA levels were studied by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and quantitative RT-PCR. Virus coat...
Tipo: Journal article
Palavras-chave: Lettuce big-vein disease; Symptom expression.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100008

Comparison of Gridded and Measured Rainfall Data for Basin-scale Hydrological Studies
Provedor de dados: 117
Autores: Muñoz,Enrique; Álvarez,César; Billib,Max; Arumí,José Luis; Rivera,Diego.
Global gridded climatological (GGC) datasets, including precipitation and temperature, are becoming more and more precise, accessible, and common, but the utility of these datasets and their limits for hydrological research are still not well determined. In this paper, we compare the performance of two hydrological models that are identical in structure but built with two different inputs: rainfall from rain gauge stations and from a GGC dataset. The objective is to evaluate the utility of gridded datasets in water resource availability studies mainly for hydroelectric and agricultural purposes. The Andean basin of the Laja River, located in south-central Chile, was chosen for this study. It was based on an 18-yr simulation, and it was concluded that i)...
Tipo: Journal article
Palavras-chave: Flow simulation; Monthly water balance; Surface water hydrology; Water resources.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300018

Compounds Derived from Garlic as Bud Induction Agents in Organic Farming of Table Grape
Provedor de dados: 117
Autores: Vargas-Arispuro,Irasema; Corrales-Maldonado,Consuelo; Martínez-Téllez,Miguel Ángel.
Viticulture is one of the most important economic activities in the Northwest of Mexico. A major obstacle for the economic production is the insufficient period of chilling temperatures. This problem leads to poor budbreak, which in turn results in reduced yields. This problem is aggravated when plants are cultivated using the organic farming system, mostly because there are not organically approved restbreaking agents. In this work different products derived from garlic (Allium sativum L.) were obtained and evaluated as stimulate budbreak agent of table grape (Vitis vinifera L.) cvs. Flame Seedless and Perlette. The isolated compounds were chemically identified and include allicin, diallyl disulfide, diallyl trisulfide, 3-vynil-[4H]-1,2-ditiin and...
Tipo: Journal article
Palavras-chave: Flame Seedless; Perlette; Budbreak; Allicin; S-methyl cysteine sulfoxide.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100009

Effects of some Insecticides Applied in Sublethal Concentrations on the Survival and Longevity of Aphidius ervi (Haliday) (Hymenoptera: Aphidiidae) Adults
Provedor de dados: 117
Autores: Araya,Jaime E.; Araya,Manuel; Guerrero,María Angélica.
The effects of four insecticides (dimethoate, pirimicarb, imidacloprid, and spinosad) applied in an ST4 Potter tower at sublethal concentrations (50% of those recommended commercially for aphid control) were studied in the laboratory on aphidiid Aphidius ervi (Haliday) adults, an important parasitoid of the pea aphid Acyrthosiphon pisum (Harris). The most selective treatment on the hymenopteran was imidacloprid, followed in decreasing order by spinosad, pirimicarb, and finally dimethoate, which quickly eliminated the parasitoid and thus its capacity to produce progeny. Three toxicity groups were distinguished in the study. The least damaging treatment to adults of A. ervi was imidacloprid, followed by a group of medium toxicity made up of spinosad and...
Tipo: Journal article
Palavras-chave: Dimethoate; Green pea aphid; Imidacloprid; Pirimicarb; Spinosad.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200005

Estimating Monthly Solar Radiation in South-Central Chile
Provedor de dados: 117
Autores: Álvarez,José; Mitasova,Helena; Allen,H. Lee.
Solar radiation is a key component in process-based models. The amount of this energy depends on the location, time of the year, and atmospheric conditions. Several equations and models have been developed for different conditions using historical data from weather station networks or satellite measurements. However, solar radiation estimates are too local since they rely on weather stations or have a resolution that is too coarse when working with satellites. In this study, we estimated monthly global solar radiation for the south-central region of Chile using the r.sun model and validated it with observations from automatic weather stations. We analyzed the performance of global radiation results with the Hargreaves-Samani (HS) and Bristow-Campbell (BC)...
Tipo: Journal article
Palavras-chave: Solar radiation; R. sun model.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400016

Microbial protein synthesis in young steers fed with grass silage and extruded corn
Provedor de dados: 117
Autores: Barchiesi-Ferrari,Claudia; Anrique,René.
Microbial protein synthesis is essential to meet protein requirements in ruminants. The aim of this investigation was to evaluate the effect of incorporating extruded corn (Zea mays L.) into the ration of young steers fed with grass silage on microbial protein synthesis (MPS). Twenty young steers in metabolic cages were used for supplying food. The treatments consisted of combinations of extruded corn (EC) and ground corn (GC) EC-10 (10% EC-30% GC); EC-25 (25% EC-15% GC) and EC-40 (40% EC-0% GC). These foods constituted 40% of the ration (DM-based) and the remaining 60% was grass silage. The MPS was calculated through the excretion of purine derivatives (PD) in the urine, using total collection of urine. The inclusion of a higher percentage of extruded...
Tipo: Journal article
Palavras-chave: Purine derivatives; Extrusion; Allantoin; Microbial protein synthesis; Zea mays.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400012

Organic Matter Reduces Copper Toxicity for the Earthworm Eisenia fetida in Soils from Mining Areas in Central Chile
Provedor de dados: 117
Autores: Ávila,Gonzalo; Gaete,Hernán; Sauvé,Sébastien; Neaman,Alexander.
The Aconcagua River basin (Central Chile) is one of the most important agricultural areas in the country. However, several copper (Cu) mining operations are located in the basin. The objective of the study was to determine Cu toxicity for the earthworm Eisenia fetida (Savigny 1826) in the agricultural soils of the basin. We determined the production of cocoons and juveniles of earthworms in the studied soils. The soils differed in the concentrations of organic matter (OM, range 2-6%), pH (range 7.3-8.3), texture (from loamy sand to clay loam), and total Cu concentrations (range 230-960 mg kg-1). Concentrations of Cu and OM in the soils were the variables that determined the earthworms’ biological response. In contrast, pH and texture did not affect this...
Tipo: Journal article
Palavras-chave: Aconcagua River; Ecological risk assessment; Cu mining; Trace elements.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200015

Relation between Seed Appearance and Phenolic Maturity: A Case Study Using Grapes cv. Carménère
Provedor de dados: 117
Autores: Fredes,Claudio; Von Bennewitz,Eduardo; Holzapfel,Eduardo; Saavedra,Felipe.
Sensory evaluation of grapes (Vitis vinifera L.) plays a key role in determining the harvest time in grapevine varieties. The harvest time of cv. Carménère is one of the latest of Chile. During the season 2007-2008, the evolution of the appearance of ‘Carménère’ seeds was evaluated as a harvest criterion, comparing it with the chemical and phenolic ripening. The samples were obtained from an organic vineyard located in Curicó Valley, Chile. Starting at 16 ºBrix, 100 seed berries samples were collected weekly from medium vigor vines in order to register photographically the ventral and dorsal sides of each seed. In addition to the seed tannins percentage, the extractable anthocyanins, total anthocyanins and total polyphenols index, as well as the titratable...
Tipo: Journal article
Palavras-chave: Seed development; Harvest index; Seed color; Phenols.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300005

Institutional Aspects of Sustainability for Irrigated Agriculture in Arid and Semi-Arid Regions
Provedor de dados: 117
Autores: del Callejo,Iván; Cossío,Vladimir.
Concerns, arguments, and approaches to sustainability are exposed in both scientific and technical irrigation literature which is based on the priority of food production and water preservation as a basic resource. Different approaches related to sustainable irrigated agriculture are identified beyond the technical considerations of irrigation as dealt with by very specialized scientific literature. These focus on socio-economic and institutional aspects of irrigation management. In this chapter, four main approaches are discussed: “New institutionalism” is an approach which emphasizes economic and financial issues such as cost recovery and the role of the market in water rights reallocation. A second approach, “Common pool resources management” highlights...
Tipo: Journal article
Palavras-chave: Institutional approaches; Irrigation institutions; Water management; Sustainable irrigation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500005

Antifungal activity of medicinal plant extracts against phytopathogenic fungus Alternaria spp
Provedor de dados: 117
Autores: Díaz Dellavalle,Paola; Cabrera,Andrea; Alem,Diego; Larrañaga,Patricia; Ferreira,Fernando; Dalla Rizza,Marco.
The aim of the study was to evaluate the antifungal activity of extracts of 10 plant species used in traditional Uruguayan medicine against the phytopathogenic fungus Alternaria spp. The plants were selected on the basis of their reported ethnobotanical uses. Aqueous, saline buffer and acid extracts of different plant species were screened in vitro for their antifungal activity against Alternaria spp. For the antifungal evaluation we used a microspectrophotometric assay. Minimal inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the extracts were determined. Three solvents were assayed on different tissues of the plants and among the 29 evaluated extracts, 31% of the extracts inhibited growth, similar to the effects of a chemical...
Tipo: Journal article
Palavras-chave: Fungicidalproperties; Ethnobotanical uses; Uruguay.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200008

Characterization of the Weed Seed Bank in Zero and Conventional Tillage in Central Chile
Provedor de dados: 117
Autores: Peralta Caroca,Rosa; Silva Candia,Paola; Acevedo Hinojosa,Edmundo.
We studied the abundance, species composition, and depth distribution of the weed seed bank under no-tillage (NT) and conventional tillage (CT) at two sites, A and B. Soil samples were taken at three soil depths (0-2, 2-5, and 5-15 cm). Germinated, dormant, and total seeds were counted. The total number of seeds was higher (p &amp;#8804; 0.05) under CT treatment at the two sites (CTA = 5175 seeds m-2, NTA = 3250 seeds m-2, CTB = 33770 m-2, and NTB = 22437 seeds m-2). The number of viable, dormant, and germinated seeds was also higher (p &amp;#8804; 0.05) in CT at the two sites. The percentage of viable seeds was low with 37% (CTA), 34% (CTB), 21% (NTA), and 8% (NTB). Viable seeds of Chenopodium album L. (CHEAL) dominated in the two trials with 67% (CTA),...
Tipo: Journal article
Palavras-chave: No-tillage species composition abundance; Depth distribution.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100017

Evaluation of Trichoderma spp. and Clonostachys spp. Strains to Control Fusarium circinatum in Pinus radiata Seedlings
Provedor de dados: 117
Autores: Moraga-Suazo,Priscila; Opazo,Alex; Zaldúa,Salomé; González,Gastón; Sanfuentes,Eugenio.
The fungus Fusarium circinatum Nirenberg &amp;amp; O’Donnell causes pine pitch canker, an important disease for conifers worldwide. F. circinatum was first detected in Chile in 2001 and to date is present in nurseries and clonal hedges from Libertador General Bernardo O’Higgins Region to Los Rios Region. The purpose of this study was to evaluate the potential of Trichoderma spp. and Clonostachys spp. strains to control F. circinatum in Pinus radiata D. Don seedlings in the absence of other effective control methods. Eighty-one Trichoderma spp. and Clonostachys spp. strains were evaluated through in vitro assays to determine their ability to act as antagonists of F. circinatum and 21 strains were tested for their ability to reduce post-emergence mortality...
Tipo: Journal article
Palavras-chave: Antagonists; Biological control; Seedling death; Pitch canker.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300011

Effects of elevated air temperature on physiological characteristics of flag leaves and grain yield in rice
Provedor de dados: 117
Autores: Qi-Hua,Liu; Xiu,Wu; Tian,Li; Jia-Qing,Ma; Xue-Biao,Zhou.
As an indispensable environment element for crop growth, air temperature has brought challenge for the sustainable development of rice (Oryza sativa L.) production. Elevated air temperature led to great loss in rice grain yield in many districts suffering from heat stress due to the greenhouse effect worldwide, which has received more and more attention from researchers. A field experiment was conducted to investigate impacts of high air temperature (HAT) after rice heading stage on dynamics of SPAD values, soluble sugar, soluble protein, and malondialdehyde (MDA) contents of flag leaves, and grain yield attributes. The results showed that HAT significantly reduced SPAD values, soluble sugar and protein contents, seed-setting rate, number of filled grains...
Tipo: Journal article
Palavras-chave: Physiological parameters; Dynamics; Yield attributes.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200001

Inorganic Nutritional Composition of Common Bean (Phaseolus vulgaris L.) Genotypes Race Chile
Provedor de dados: 117
Autores: Paredes C,Mario; Becerra V,Viviana; Tay U,Juan.
The current Chilean bean (Phaseolus vulgaris L.) collection is about 1110 accessions. To facilitate the characterization of this germplasm a core collection of 246 accessions was formed. Little information exists about the mineral content and other quality traits for those bean genotypes. This information could be useful to determine their quality and to promote its consumption. The objective of this work was to evaluate the variability for macro and micronutrients of a representative bean sample from a Chilean core collection and to compare them with representatives from other races. The results indicated the presence of a wide variability for some macro and micronutrients, such as N, Fe, and Zn. The protein content varied from 183.5 to 259.7 g kg-1, Fe...
Tipo: Journal article
Palavras-chave: Race Chile; Macronutrients; Micronutrients; Core collection.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400002

Importance of Abscisic Acid (ABA) in the In Vitro Conservation of Cassava (Manihot esculenta Crantz)
Provedor de dados: 117
Autores: Barrueto Cid,L. Pedro; Carvalho,Luiz L.C.B.
The conventional technology for in vitro plant conservation for cassava (Manihot esculenta Crantz) germplasm collections is laborious due to the need for several sub-culturing procedures per year. This practice implies high costs for medium preparation, tissue culture tubes, time-consuming labor, risks of contamination, mislabeling of accession, and the need for large growth chambers. We have developed a new procedure using in vitro cultivated nodal axillary buds treated with different abscisic acid (ABA) concentrations to reduce the time for recycling transplants cultivated in a SP basic nutritive medium. Nodal explants were stored for three months with ABA. Plants were obtained after nodal axillary buds were placed in SP medium without ABA. Results...
Tipo: Journal article
Palavras-chave: Tissue culture; Dormancy.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300011

Millán-INIA, New Variety of High Quality Early Spring Bread Wheat for Irrigated Soils in Central-Southern Chile
Provedor de dados: 117
Autores: Matus,Iván; Madariaga,Ricardo; Jobet,Claudio; Zúñiga,Javier; Alfaro,Christian.
Millán-INIA is a variety of spring bread wheat (Triticum aestivum L.) originating from a cross carried out in the Wheat Plant Breeding Project of the Instituto de Investigaciones Agropecuarias (INIA), in the Centro Regional de Investigación Quilamapu in 1995. This is a spring wheat variety with an early to medium-early head emergence and upright growth habit in the seedling stage. The adult plant is low to medium height and varies between 75 and 90 cm, with a mean of 85 cm. The spike is white with long awns along its full length. The grain is large-sized, white, and vitreous. The weight of 1000 grains varies between 50 and 59 g. It was sown in mid-August at the Santa Rosa Experimental Station (36°31’ S; 71°54’ W), Chillán. Head emergence occurred 88 to 89...
Tipo: Journal article
Palavras-chave: Spring wheat; New variety; Millán-INIA.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200019

Impact of climate change on oil fatty acid composition of peanut (Arachis hypogaea L.) in three market classes
Provedor de dados: 117
Autores: Onemli,Fadul.
Peanut (Arachis hypogaea L.) is one of the most important oilseed crops of the world. The fatty acid composition plays an important role in oil quality. Experiments were performed to examine the variation in oil fatty acids of three normal oleic peanut market types (Virginia, Valencia, and Spanish) in 2008, 2009, and 2010. Variations of botanical variety, year and their interaction were highly significant for oil content and all 13 fatty acids studied. Oil content in different peanut market types exhibited significant differences. The maximum oil content (51.993%) was found in Virginia (NC-7), while Valencia (New Mexico Valencia A) accumulated the minimum oil content (47.197%). Virginia had also the highest oleic acid percentage. Higher temperatures during...
Tipo: Journal article
Palavras-chave: Arachis hypogaea subsp. fastigiata; Temperature; Correlation.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400004

Effect of Pheromone Trap Density on Mass Trapping of Male Potato Tuber Moth Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), and Level of Damage on Potato Tubers
Provedor de dados: 117
Autores: Larraín S,Patricia; Guillon,Michel; Kalazich,Julio; Graña,Fernando; Vásquez,Claudia.
Potato tuber moth (PTM), Phthorimaea operculella (Zeller), is one of the pests that cause the most damage to potatoes (Solanum tuberosum L.) in both field crops and storage, especially in regions where summers are hot and dry. Larvae develop in the foliage and tubers of potatoes and cause direct losses of edible product. The use of synthetic pheromones that interfere with insect mating for pest control has been widely demonstrated in numerous Lepidoptera and other insect species. An experiment was carried out during the 2004-2005 season in Valle del Elqui, Coquimbo Region, Chile, to evaluate the effectiveness of different pheromone trap densities to capture P. operculella males for future development of a mass trapping technique, and a subsequent decrease...
Tipo: Journal article
Palavras-chave: Potato tuber moth; Mass trapping; Pheromone.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200018

Potential Protein Deposition in the European Wild Boar (Sus scrofa L.)
Provedor de dados: 117
Autores: Quijada,Roberto P; Hodgkinson,Suzanne M.
The growth rate of farmed European wild boars (Sus scrofa L.) is perceived to be very slow. However, there is no available information on the genetic potential of these animals in terms of potential lean tissue growth.The aim of the study was to determine the maximum capacity for protein deposition (operational PDmax) in wild boars under controlled environmental conditions. Four diets were formulated containing different levels of digestible energy (DE): 2.2, 2.4, 2.6, and 2.8 Mcal DE kg-1. All of the diets contained at least 5 g lysine per Mcal DE. Twenty purebred wild boars from a commercial farm of the same age (± 4 d) and with an initial liveweight of 27 ± 0.50 kg (mean ± standard error of the mean) were used in the study. At the beginning of the study...
Tipo: Journal article
Palavras-chave: Protein deposition; Digestible energy; Wild boar.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200020

A Ricardian Analysis of the Impact of Climate Change on South American Farms
Provedor de dados: 117
Autores: Niggol Seo,S; Mendelsohn,Robert.
This study estimates the impact of climate change on South American agriculture taking into account farm adaptations. The study used a Ricardian analysis of 2300 farms to explore the effects of global warming on land values. In order to predict climate change impacts for this century, were examined climate change scenarios predicted by three Atmospheric Oceanic General Circulation Models (AOGCM): the Canadian Climate Center (CCC), the Centre for Climate System Research (CCSR), and the Parallel Climate Model (PCM) models. Several econometric specifications were tested, and five separate regressions were run: for all farms, small household farms, large commercial farms, rainfed farms, and irrigated farms. Farmland values will decrease as temperature...
Tipo: Journal article
Palavras-chave: Climate change; Agriculture; Ricardian approach; South America.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100007

Export Behaviour in the Chilean Agribusiness and Food Processing Industry
Provedor de dados: 117
Autores: Echeverría,Rodrigo; Gopinath,Munisamy.
This paper analyzes the export-behavior of Chilean agribusiness and food processing firms and the relative importance of firm-specific and geographic characteristics in this behavior. Using firm level data and regional geographic indicators, a dynamic model was used to study the export decisions and the export intensity of three industries: processing fish, processing fruits and vegetables, and wine production. Results showed that determinants of exporting behavior vary among the three industries, except the effect of sunk costs, which strongly impacts the export decisions of all analyzed industries. This implies that firms with prior export experience will have higher probability of exporting in the future. Foreign ownership positively impacts the export...
Tipo: Journal article
Palavras-chave: Agricultural trade; Export decision; Export intensity; Geography.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400007

Use of Cellulases to Predict in vivo Digestible Organic Matter (D value) in Pasture Silages
Provedor de dados: 117
Autores: Barchiesi-Ferrari,Claudia; Alomar,Daniel; Miranda,Horacio.
In pasture-based dairy herds where silage is a widely adopted supplement, optimized feeding requires reliable estimations of nutritional quality of this conserved forage. Metabolizable energy, an important nutritional fraction, can be predicted from digestibility-related traits, such as the digestible organic matter contained in the dry matter (D-value). The aim of the present study was to evaluate the prediction of D-value and dry matter digestibility (DMD) of grass silages made from four different pastures and maturity stages, using the pepsin-cellulase method. Fungal cellulase was used, applying different enzyme concentrations, incubation times and types of final wash. The silages were prepared from permanent pasture (Dactylis glomerata L., Lolium...
Tipo: Journal article
Palavras-chave: Pasture silage; Digestibility of dry matter.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200011

Chemical and Nutritional Composition of Copao Fruit (Eulychnia acida Phil.) Unswe Thee Environmental Conditions in the Coquimbo Region
Provedor de dados: 117
Autores: Masson S,Lilia; Salvatierra,María Angélica; Robert C,Paz; Encina A,Cristian; Camilo M,Conrado.
Copao (Eulychnia acida Phil.) is an endemic arborescent cactus restricted mainly to the semi-arid Coquimbo Region (29°54'28" S, 71°15'15" W), Chile. The area of distribution is from sea level to 1200 m.a.s.l. The edible fruit called rumpa is generally round, with green or pink peel and small scales on its surface, showing wide variability in size and weight. The aim of this work was to characterize the rumpa harvested in January 2009 and 2010 in three sectors of Coquimbo Region to determine chemical and nutritional composition in three fractions: pulp with seeds, juice, and peel. The research showed that this fruit is a good natural source of mainly soluble dietary fiber, which has a jellied texture and is present in the three fractions analyzed: 2% for...
Tipo: Journal article
Palavras-chave: Rumpa; Arborescent cactus; Vitamin C; Minerals.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400004

Chemical composition, insecticidal, and antifungal activities of fruit essential oils of three colombian Zanthoxylum species
Provedor de dados: 117
Autores: Prieto,Juliet A; Patiño,Oscar J; Delgado,Wilman A; Moreno,Jenny P; Cuca,Luis E.
This study determined the chemical composition of essential oils isolated from Zanthoxylum monophyllum (Lam.) P. Wilson, Z. rhoifolium Lam., and Z. fagara (L.) Sarg. fruits by steam distillation, as well as testing antifungal and insecticidal activities of essential oils as potential pesticides. Gas chromatography-mass spectrometry (GC/MS) analysis identified 57 compounds. The main constituents in Z. rhoifolium oil were &amp;#946;-Myrcene (59.03%), &amp;#946;-phellandrene (21.47%), and germacrene D (9.28%) , the major constituents of Z. monophyllum oil were sabinene (25.71%), 1,8-cineole (9.19%), and cis-4-thujanol (9.19%), whereas fruit oil of Z. fagara mainly contained germacrene D-4-ol (21.1%), elemol (8.35%), and &amp;#945;-cadinol (8.22%). Zanthoxylum...
Tipo: Journal article
Palavras-chave: Fumigant; Antifungal; Insecticidal.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100009

Influence of Waiting Time after Insertion of Base Chamber into Soil on Produced Greenhouse Gas Fluxes
Provedor de dados: 117
Autores: Muñoz,Cristina; Saggar,Surinder; Berben,Peter; Giltrap,Donna; Jha,Neha.
The soil chamber technique is most commonly used for measuring gas exchange between soil surfaces and the atmosphere, to understand regulatory processes relevant to determine the greenhouse gas (GHG) emissions from soils and to improve the emissions inventory of agricultural systems. The chambers are inserted into the soil to avoid the lateral diffusion of the gases. However, soil disturbance caused by chamber insertion causes in degassing and can result in erroneous flux data from measurements made immediately following chamber insertion. Here we assess the effect of soil disturbance associated with the insertion of the chambers on nitrous oxide (N2O) and methane (CH4) fluxes with and without N fertilization, from a New Zealand pasture soil. We collected...
Tipo: Journal article
Palavras-chave: Nitrous oxide; Methane; Agricultural soil; Soil biological processes; Gases monitoring.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400017

Effect of Grazing Systems on Range Condition in Pabbi Hills Reserve Forest, Kharian, Punjab, Pakistan
Provedor de dados: 117
Autores: Sajjad Haider,Muhammad; Maclaurin,Angus; Ali Chaudhry,Amjad; Mushtaque,Muhammad; Ullah,Sami.
Grazing management of rangeland systems has not been well researched in Pakistan; grazing system the most sustainable is not known. In order to evaluate various grazing systems, a study was performed at Pabbi Hills Reserve Forest, Kharian, Punjab. Four simulated grazing treatments, viz. ungrazed control, continuous grazing, seasonal deferred grazing, and rotational deferred grazing, were tested in a randomized complete block design with four replicates. Response variables included species composition, fresh herbage yield, dry herbage yield of grasses and forbs, basal cover, and ground cover. Of the three grazing systems, the six-month seasonal deferred grazing system resulted in a marked increase in basal cover, but had no changes in relative species...
Tipo: Journal article
Palavras-chave: Sustainable rangeland system; Basal cover; Species composition; Herbage production; Ground cover; Six-month seasonal deferred grazing system.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400010

Implementation and Evaluation of an Image Analysis System for Determining Viability of Pollen Grains in Temperate Rice
Provedor de dados: 117
Autores: Ortega B,Rodrigo; Aresti E,Macarena; Pereira R,Iris.
Geographical and climatic factors limit the production of temperate rice (Oryza sativa L.) in Chile. Large thermal fluctuations of air and water temperatures affect the viability of pollen, causing high levels of spikelet sterility (”blanking”), resulting in reduced yields per hectare. Counting viable pollen grains, at the time of anthesis, may allow determining, ahead, whether there will be yield losses by spikelet sterility; besides, knowing the potential pollen viability serves as a powerful tool for material selection in breeding programs, and for determining which management factors may influence ”blanking”. If performed manually, counting total and viable pollen grains can be extremely tedious, producing highly variable results. The present work had...
Tipo: Journal article
Palavras-chave: Rice crop; Pollen counting; Image analysis; Anthesis; Spikelet sterility.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100002

Growth, yield, and fruit quality of 'Rhode Red Valencia' and 'Valencia Late' sweet oranges grown on three rootstocks in eastern Mediterranean
Provedor de dados: 117
Autores: Yildiz,Ercan; Hakan Demirkeser,Turan; Kaplankiran,Mustafa.
The plant growth, yield, yield efficiency, and fruit quality of 'Rhode Red Valencia' and 'Valencia Late' sweet oranges (Citrus sinensis (L.) Osbeck) on three rootstocks were evaluated under Eastern Mediterranean climatic conditions of Dortyol-Hatay, which is one of the oldest and largest citrus and mandarin (Citrus reticulata Blanco) production regions in Turkey. The fruit yield was affected by rootstock in both scion cultivars from 2007 through 2010. Trees on 'Troyer' citrange had lower yield than those budded on the other rootstocks. The yield of 'Rhode Red Valencia' and 'Valencia Late' orange trees on 'Carrizo' citrange were about 9% and 19% more than those on 'Troyer' citrange, respectively. But trees on 'Troyer' citrange had significant higher yield...
Tipo: Journal article
Palavras-chave: Orange; Rootstock; Fruit quality; Plant characteristics; Yield.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200009

Use of Analytic Factor Structure to Increase Heritability of Clonal Progeny Tests of Pinus taeda L.
Provedor de dados: 117
Autores: Zapata-Valenzuela,Jaime.
Advanced variance-covariance structures are commonly used in genetic evaluation of crops to account for micro-site variability and achieve higher accuracy of predictions to increase selection efficiency. Various genetic variance-covariance structures were explored to predict best linear unbiased genetic merits of 453 loblolly pine (Pinus taeda L.) cloned progeny tested at 16 different locations in the southern U.S. Statistical models were compared using model fit statistics, variance components and genetic parameters. Among the models explored, spatial autoregressive error correlation with independent residual term for the R side with a factor analytic structure for the G side of the mixed model was superior. The model produced one of the smallest fit...
Tipo: Journal article
Palavras-chave: Linear mixed model; Quantitative forest genetics; Genetic variance.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300002

Genetic Relationships of Common Bean (Phaseolus vulgaris L.) Race Chile with Wild Andean and Mesoamerican Germplasm
Provedor de dados: 117
Autores: Becerra V,Viviana; Paredes C,Mario; Debouck,Daniel.
The Chilean common bean (Phaseolus vulgaris L.) belongs to the cultivated race Chile and its origin is presumably Andean. The objective of this study was to identify the origin of a group of Chilean accessions based on their genetic relationship with wild material from the Mesoamerican and Andean common bean gene pool. To achieve this objective, universal primers of chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) were used to detect polymorphism using Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP). Thirty-two genotypes were analyzed, including wild material from Mexico, Ecuador, Peru, Bolivia, and Argentina, as well as Chilean cultivated genotypes belonging to endemic Chilean accession types (Tórtola, Coscorrón, and...
Tipo: Journal article
Palavras-chave: Chilean common bean germplasm; Chloroplast DNA; Mitochondrial DNA; PCR-RFLP.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100001

Over-summering of wheat stripe rust (Puccinia striiformis f.sp. tritici) in the California Central valley: A case study
Provedor de dados: 117
Autores: Tollenaar,Huib.
To study the over-summering of wheat stripe rust (Puccinia striiformis f.sp. tritici) in the California Central Valley (CCV), temperature records from various locations in the CCV during the period 1950-2009 were examined for the occurrence of lethal maximum temperatures for the uredinia and uredinio-mycelium of this fungus. The lethal upper threshold temperature for the uredinial stage of P.s. tritici, estimated to be 40.5 °C on the basis of data published elsewhere, and the sum, accumulated during ten consecutive days, of the respective lethal temperature quotients (ALTQio), accounting for the partial lethal effect of the daily ambient temperatures between 30 and 40.5 °C on the uredinial stage of P.s. tritici, were used as yardsticks for thermal...
Tipo: Journal article
Palavras-chave: Yellow rust; Epidemiology; Lethal temperature; Triticum aestivum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400005

Availability of Nitrogen, Phosphorus and Potassium from Poultry Litter and Conventional Fertilizers in a Volcanic Soil Cultivated with Silage Corn
Provedor de dados: 117
Autores: Hirzel,Juan; Walter,Ingrid.
Poultry litter (PL) is an organic matter source used as soil amendment. Besides its important nutrient content, it is a cheap alternative to conventional fertilizers in crop production. The efficient use of PL also helps reduce the environmental problems normally associated with its disposal near poultry production farms. This article reports the relative effects of PL and conventional fertilizers on the availability of soil N, P and K, dry matter (DM) production and total nutrient content in silage corn (Zea mays L.). The field experiment was carried out in a soil derived from volcanic ash (Tipic Melanoxerands) of Central South Chile. Corn was grown for three seasons (2002-2005) and PL and conventional fertilizers were applied in the first two years. The...
Tipo: Journal article
Palavras-chave: Poultry litter; Soil fertility; Corn; Nitrogen; Phosphorus; Potassium.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300006

Leaf Surface Scanning Electron Microscopy of 16 Mulberry Genotypes (Morus spp.) with Respect to their Feeding Value in Silkworm (Bombyx mori L.) Rearing
Provedor de dados: 117
Autores: Singhal,B.K; Baqual,M.F; Khan,M.A; Bindroo,B.B; Dhar,A.
Mulberry (Morus spp.) is the only silkworm (Bombyx mori L.) food plant. In Indian sub tropics, S-146 is the only popular and ruling mulberry genotype for silkworm rearing. As a result, mulberry leaf availability is always the limiting factor, and therefore, sub tropics are contributing less than 1% of the country’s total silk production compared with more than 60% under tropical conditions. Besides climatic conditions, this is due to a very limited number of mulberry genotypes available in this region for silkworm rearing. However, in the mean time, 15 mulberry genotypes viz. &amp;#8216;Tr-10&amp;#8217;,&amp;#8216;Chinese White&amp;#8217;,&amp;#8216;K-2&amp;#8217;,&amp;#8216;Sujanpur...
Tipo: Journal article
Palavras-chave: Scanning electron microscopy; Stomata; Trichomes; Idioblasts; Leaf yield; Sericulture.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200001

Feeding Dry Olive Cake Modifies Subcutaneous Fat Composition in Lambs, Noting Cake Resistance to Degradation and Peroxidation
Provedor de dados: 117
Autores: Vera,Raúl; Aguilar,Claudio; Lira,Rodrigo; Toro,Paula; Barrales,Luis; Peña,Iván; Squella,Fernando; Pérez,Patricio; Quenaya,Javiera; Yutronic,Hanja; Briones,Ignacio.
The purpose of this experiment was to determine the extent to which lamb carcass quality and fat composition could be altered by applying a dry olive cake-based ration instead of a conventional ration or pasture feeding. Three treatments were compared in a completely randomized experiment using 36 single male Suffolk Down lambs with an initial age and live weight of 80 d and 25 kg, respectively. The three treatments were: (a) suckling lambs kept with their mothers on annual Mediterranean grassland (GRAZE); (b) weaned stall-fed lambs on a control ration (CONC); and (c) weaned stall-fed lambs on an olive cake-based ration (CAKE). At the end of the 28-d experimental period, lambs were slaughtered, carcass quality evaluated, and samples of subcutaneous fat...
Tipo: Journal article
Palavras-chave: Sheep; Dry olive cake; Fatty acids; Body composition.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400010

Gene action and combining ability of yield and its components for late kharif season in okra (Abelmoschus esculentus (L.) Moench)
Provedor de dados: 117
Autores: Thirupathi Reddy,Medagam; Hari Babu,Kadiyala; Ganesh,Mutyala; Begum,Hameedunnisa; Dilipbabu,Jampala; Krishna Reddy,Reddivenkatagari Subbarama.
Knowledge on the genetic system controlling the quantitative traits is important for devising an efficient selection program through the use of a suitable mating design. Forty five Fis were generated by crossing 10 germplasm lines of okra (Abelmoschus esculentus (L.) Moench) namely P1(IC282248), P2(IC27826-A), P3(IC29119-B), P4(IC31398-A), P5(IC45732), P6(IC89819), P7(IC89976), P8(IC90107), P9(IC99716), and P10(IC111443) during summer 2009. Forty five F1s along with their 10 parents were evaluated in a randomized block design with three replicates during late kharif (August-November) 2009 at Vegetable Research Station, Hyderabad, Andhra Pradesh, India, for studying gene action and combining ability of yield and its components. Significant general combining...
Tipo: Journal article
Palavras-chave: Fruit yield; Genetic analysis.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100002

Effects of Nitrogen on Productivity, Grain Quality, and Optimal Nitrogen Rates in Winter Wheat cv. Kumpa-INIA in Andisols of Southern Chile
Provedor de dados: 117
Autores: Campillo,Ricardo; Jobet,Claudio; Undurraga,Pablo.
Nitrogen is one of the main inputs of the winter wheat crop (Triticum aestivum L.) in southern Chile. Nitrogen efficient management is basic to optimizing its utilization while decreasing pollution risks and operational costs. Crop response and N use efficiency (NUE, defined as the ratio of yield to mineral N supply, regardless of source) are important for evaluating N requirements of winter wheat, and reaching maximum and economic yields. The objective of this study was to determine the effect of N rate on grain yield, calculate the N rate that maximizes yield, and estimate the optimal grain yield rate and quality of high-yielding winter wheat cv. Kumpa-INIA. Five annual N rates were evaluated in a randomized complete block design during two successive...
Tipo: Journal article
Palavras-chave: Nitrogen level; Nitrogen use efficiency; Andisols.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100013

Endophytic Bacteria from Pinus taeda L. as Biocontrol Agents of Fusarium circinatum Nirenberg &amp;amp; O'Donnell
Provedor de dados: 117
Autores: Soria,Silvina; Alonso,Raquel; Bettucci,Lina.
Fusarium circinatum Nirenberg &amp;amp; O'Donnell, the pitch canker fungus, has been recently reported in Uruguay affecting Pinus taeda L. seedlings. The spread of this pathogen to plantations constitute a risk to forestry production. The aim of this work was to evaluate the inhibitory effect of live bacteria and their thermostable metabolites on F. circinatum growth in vitro. Four Bacillus subtilis strains and one of Burkholderia sp. isolated as P. taeda endophytes were evaluated as biological control agents of F. circinatum. Dual cultures between live bacteria and pathogen were performed. Furthermore, bacteria metabolites obtained from liquid cultures were sterilized and added to the culture media where fungus was grown. In this study all bacteria showed...
Tipo: Journal article
Palavras-chave: Biological control; Pitch canker.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200018

Botanical Composition of Alpaca (Lama pacos Linn.) Diet in a Central Mediterranean Range of Chile
Provedor de dados: 117
Autores: Castellaro,G; Squella N,F; León C,F; Raggi S,A.
The re-introduction of domestic South American camelids (alpacas and llamas) in the central zone of Chile makes it necessary to study their behaviour and adaptability. Since it is fundamental to characterize the camelid’s diet, the present work had as an objective the determination of the plant species selected by the alpacas (Lama pacos Linn.) in different phenological stages (vegetative, reproductive and dry season). The study was carried out over three years in a paddock of 2.5 ha of sparse shrubland dominated by Acacia caven (Mol.) Mol. and annual species in the herbaceous stratum, which were continually grazed by five male alpacas. The botanical composition and the forage dry matter available for grazing in the pasture was evaluated. Botanical...
Tipo: Journal article
Palavras-chave: Alpaca; Annual Mediterranean range; Botanical composition; Microhistology.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200003

Evaluation of the Water Requirements for a Greenhouse Tomato Crop using the Priestley-Taylor Method
Provedor de dados: 117
Autores: Valdés-Gómez,Héctor; Ortega-Farías,Samuel; Argote,Mauricio.
The Priestley-Taylor (PT) model was evaluated for estimating the real evapotranspiration (ETreal) of a drip-irrigated greenhouse tomato (Lycopersicon esculentum Mill.) crop. The net radiation incorporated in the PT model was estimated using meteorological variables. For this experiment, an automatic weather station (AWS) was installed inside the greenhouse to measure solar radiation (Rgi), net radiation (Rn), air temperature (Ta) and relative humidity (RH). Another AWS was installed over a grass cover to measure atmospheric conditions outside the greenhouse. The experiment was carried out at the Panguilemo experimental station (35°23' S, 71°40' W, 110 m.a.s.l.) from August to December 2000. The PT model was evaluated using the ETreal obtained from the...
Tipo: Journal article
Palavras-chave: Irrigation; Model; Crop coefficients; Net radiation; Soil heat flu.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100001

Selection of Entomopathogenic Nematodes against Dalaca pallens (Lepidoptera: Hepialidae)
Provedor de dados: 117
Autores: Maldonado,Alexis; Merino,Loreto; France,Andrés.
Dalaca pallens (Blanchard) is a pest with great impact on grassland production in Chile. The objective of this research was to evaluate the use of entomopathogenic nematodes (EPN) against D. pallens larvae. Twenty EPN isolates, collected along Chile, were used for nematode selection. The experimental unit consisted of five 50-mL plastic vials filled with Nothofagus dombeyi sawdust and inoculated with 40 dauers per vial. The experimental design was a completely randomized with four replicates per treatment. The results showed that isolate QU N3 (Steinernema australe) and QU N13 (Steinernema unicornum) produced the highest mortality, with 100 and 95% respectively and no differences (P &lt; 0.001) between both. Later, these two isolates were used to calculate...
Tipo: Journal article
Palavras-chave: Biological control; Lethal concentration.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200006

Chemical constituents and toxicity of Agastache foeniculum (Pursh) kuntze essential oil against two stored-product insect pests
Provedor de dados: 117
Autores: Ebadollahi,Asgar.
The uncontrolled use of synthetic insecticides is a great hazard for the environment and consumers. Essential oils were introduced as low toxic agents against mammals and non-targeted insects. In this study, essential oil from aerial parts of blue giant hyssop (Agastache foeniculum [Pursh] Kuntze) (Lamiaceae) was isolated by the water steam distillation method with a Clevenger apparatus, and its chemical composition was studied by gas chromatography mass spectrometry. The toxicity of A. foeniculum essential oil against red flour beetle, Tribolium castaneum (Herbst), and lesser grain borer Rhyzopertha dominica (F.) was evaluated by fumigation at 24, 48, and 72 h exposure times. Estragole and 1,8-cineole were identified as major constituents of the A....
Tipo: Journal article
Palavras-chave: Blue giant hyssop; Fumigation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200005

Induction of resistance in chickpea (Cicer arietinum L.) against Ascochyta rabiei by applying chemicals and plant extracts
Provedor de dados: 117
Autores: Usman Ghazanfar,M; Wakil,Waqas; Talib Sahi,Shahbaz.
Since new fungicides are scarce in the market and because of environmental problems, researchers are now emphasizing other alternatives, such as the genetic potential of plants, resistance against pathogens, and the use of biotic and abiotic agents to develop induced or acquired resistance. We investigated the role of resistance-inducing substances (chemicals and plant extracts) in three chickpea cvs. C-44, Pb-91, and Bittle-98 in field experiments against Ascochyta blight disease. These cultivars were selected on the basis of better yield potential shown in previous experiments. Aqueous solution of salicylic acid (SA) at 0.5, 1.0, and 1.5 mM; acibenzolar-S-methyl (Bion®, ASM) at 0.4, 0.8, and 1.2 mM; and KOH at 25, 50, and 75 mM were applied, whereas...
Tipo: Journal article
Palavras-chave: Induced resistance; Acibenzolar-S-methyl; Salicylic acid.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100007

Acceptance of Transgenic Milk in La Araucania Region,Chile
Provedor de dados: 117
Autores: Schnettler M,Berta; Sepúlveda B,Oriana; Ruiz F,Danilo.
Considering the high level of concern caused by genetically modified foods (GMF) in developed countries, the relevance of this variable in decision-making about the purchase of fluid milk among consumers in Temuco (La Araucanía Region, Chile) was determined. By means of a personal survey of 400 people and using conjoint analysis, it was determined that the presence of genetic modifications in food was more important (44.7%) than brand (29.5%) and price (25.5%) in the decision-making process. By cluster analysis three segments were identified; the largest group (46.5%) gave similar relevance to food production and brand, preferring genetically modified milk. For the second group (41.5%), the presence or absence of genetic modification was the most important...
Tipo: Journal article
Palavras-chave: Genetically modified foods (GMF); Fluid milk; Cluster analysis; Conjoint analysis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400008

Participation in Organizations, Technical Efficiency and Territorial Differences: A Study of Small Wheat Farmers in Chile
Provedor de dados: 117
Autores: Jaime,Mónica M; Salazar,César A.
The lack of efficient individual solutions for small farmers either in the market or through the State has resulted in a search for collective spaces to strengthen their productive capacities, where participation in organizations emerges as a relevant factor to obtain higher efficiency levels. The aims of this study were to analyze the determinants of technical efficiency of wheat small farmers in Bío-Bío Region (Chile) and to evaluate its relation to a variety of variables, including farmer participation in organizations, for several territories with different agro-climatic conditions. Using information from the VII Agricultural and Forestry Survey, a stochastic frontier production function was estimated. The results show that age, education, farm size,...
Tipo: Journal article
Palavras-chave: Technical efficiency; Stochastic frontier production function; Participation in organizations; Social capital; Eficiencia técnica; Fronteras de producción estocásticas; Participación en organizaciones; Capital social.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100013

Potassium and Phosphorus in Muscat Rosada Grape Yield in Elqui Valley Soil
Provedor de dados: 117
Autores: Sierra B,Carlos; Alfaro P,Rubén.
The effects of P and K on grapevines (Vitis vinifera L.) var. Muscat Rosada were evaluated four years, considering the same levels of N. The experiment was conducted at the Vicuña Experimental Station (30° S; 70°44´ W) of the Instituto de Investigaciones Agropecuarias (INIA). The soil is alluvial antropic miscellaneous (Entisols). Three fertilization treatments were established: 1) N 160 + P2O5 200 + K2O 300; 2) N 160 + P2O5 0 + K2O 300; and 3) N 160 + P2O5 200 + K2O 0. At the beginning of the experiment, grape vines received all the phosphate fertilizers, 200 kg ha-1 of P2O5 as triple superphosphate in Treatments 1 and 3. Nitrogen was applied as urea for four years. The applications were initiated when the vine buds measured 20 cm. The K was applied to...
Tipo: Journal article
Palavras-chave: Grapes; Fertilization; Phosphorus; Potassium.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300010

Virulence and Pre-Lethal Reproductive Effects of Metarhizium anisopliae var. anisopliae on Pseudococcus viburni (Hemiptera: Pseudococcidae)
Provedor de dados: 117
Autores: Pereira,Aldo; Casals,Pedro; Salazar,Ana María; Gerding,Marcos.
Obscure mealybug, Pseudococcus viburni (Signoret), is a cosmopolitan pest that causes damage by suction of vascular juices and the production of honeydew, as well as for being a quarantine insect. Within control options, entomopathogenic fungi are a good alternative, nevertheless, more research is needed. In this research, the Metarhizium anisopliae var. anisopliae (Metschnikoff) isolate Qu-M984 was evaluated on P. viburni under laboratory conditions. Virulence was evaluated by lethal dose 50 (LD50) and lethal time 50 (LT50), for each of the four life stages of the female. The doses tested were 10(5), 10(6), 10(7) and 10(8) conidia mL-1. Also fecundity, egg size, fertility, and longevity of adult females were evaluated at doses of 10(5) and 10(6) conidia...
Tipo: Journal article
Palavras-chave: Lethal dose; Lethal time; Biological control; Entomopathogenic fungus; Fecundity; Fertility; Longevity.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400009

Rhizogenic Induction in Adult Juglans regia L. cv. Serr Tissue Induced by Indole Butyric Acid and Agrobacterium rhizogenes
Provedor de dados: 117
Autores: Sánchez-Olate,Manuel; Sáez,Patricia; Ríos,Darcy.
The in vitro introduction of adult walnut (Juglans regia L.) tissue represents an opportunity to clone elite genotypes whose selection occurs in advanced ontogenic states. With the purpose of developing a protocol to allow mass propagation of valuable genotypes from adult material, a comparison was made between two root induction systems of walnut microshoots of the fourth subculture of adult walnut tissue of an in vitro introduction program previously reinvigorated through traditional grafting. Rhizogenic induction by indole-3-butyric acid (IBA) and Agrobacterium rhizogenes was used. The rhizogenic process was analyzed in two phases for both auxinic (T1: 3 mg L-1 IBA; T2: 5 mg L-1 IBA) and A. rhizogenes inductions (T3: A-477; T4: A-478). The first phase...
Tipo: Journal article
Palavras-chave: Rooting; Microshoots; Adult material.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200019

Toxic and Repellent effecto of Harmal (Peganum harmala L.) Acetonic Extract on Several Aphids and Tribolium castaneum (Herbst)
Provedor de dados: 117
Autores: Salari,Elham; Ahmadi,Kamal; Dehyaghobi,Reza Zamani; Purhematy,Amin; Takalloozadeh,Haji Mohammad.
To reduce the dependence on the sometimes unwise use of synthetic pesticides in fruit and vegetable plantations, the toxicity and repellence of Peganum harmala L. (Zygophyllaceae) acetonic seed extract was assayed against several insect pests. For contact toxicity, 3- to 4-d-old individuals of Aphis fabae Scopoli, A. gossypii Glover, A. nerii Boyer de Fonscolombe, and Myzus persicae (Sulzer) were included, as well as 1- to 7-d-old adult Tribolium castaneum (Herbst). Repellent effect experiments were conducted on adult, 1- to 2- and 3- to 4-d old M.persicae individuals. At 60 mg mL4, the topical bioassay mortality percentage was significantly higher in A. gossypii than in A. fabae and A. nerii after 12-72 h. Mortality of the treatments on M.persicae was...
Tipo: Journal article
Palavras-chave: Topical bioassay; Aphid species.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100023

Plant Response to Salmon Wastes and Sewage Sludge Used as Organic Fertilizer on Two Degraded Soils Under Greenhouse Conditions
Provedor de dados: 117
Autores: Celis,José; Sandoval,Marco; Barra,Ricardo.
The potential toxicity of urban sewage and farmed salmon sludge, as well as their fertilizer potential, was evaluated by a battery of tests carried out with lettuce (Lactuca sativa L.) and annual ryegrass (Lolium multiflorum Lam.) cv. Winter Star. Wastes were evaluated in a Patagonian soil (Andic cryofluvent) and a granitic soil (Ultic Palexeralf). The treatments were municipal sewage sludge (MSS), salmon ground-farming waste (PSW) and salmon lake-farming waste (LSW) at different rates: 25, 50, 75, 100 and 150 t ha-1. Bioassays in lettuce were conducted for germination index (GI), radicle and hypocotyl structure length. Test in ryegrass were conducted for aboveground biomass yield. The phytotoxicological results from Patagonian soil showed significant...
Tipo: Journal article
Palavras-chave: Fish sludge; Salmon waste; Urban sludge; Organic fertilizer; Degraded soil.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300007

Quantifying Nitrate Leaching in Irrigated Wheat with Different Nitrogen Fertilization Strategies in an Alfisol
Provedor de dados: 117
Autores: Claret M,Marcelino; Urrutia P,Roberto; Ortega B,Rodrigo; Best S,Stanley; Valderrama V,Natalia.
Consumption of water contaminated with nitrates is associated with important health effects such as methemoglobinemia and gastric cancer. Intensive agriculture, which uses large quantities of N fertilizer, is the main source of nitrates in water systems. There are several strategies to reduce leaching and increase Nitrogen Use Efficiency (NUE). An experiment was conducted with spring wheat (Triticum aestivum L.) under sprinkler irrigation (center pivot) to determine if adjusted N applications using precision agriculture tools and plant demand resulted in a lower groundwater nitrate load. Evaluated treatments were: produced fertilization (Pr), precision agriculture (Pa), chlorophyll meter (Sm), and control without N (W/N). The ceramic capsule methodology...
Tipo: Journal article
Palavras-chave: Nitrates; Precision agriculture; Chlorophyll meter; Wheat.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100018

Glyphosate Mineralization: Effect of Temperature and Soybean and Corn Crop Residues
Provedor de dados: 117
Autores: Rampoldi,Ariel; Hang,Susana; Barriuso,Enrique.
Mineralization is the main mechanism of dissipation of glyphosate herbicide (N-[phosphonomethyl] glycine) in soil. However, there is scarce information about the mineralization process in strata formed by stubbles in no-tillage systems. The kinetics and rate of mineralization of herbicide in stubbles of soybean (Glycine max L. Merr.) and corn (Zea mays L.) were investigated. To evaluate the effect of age of crop residues, samples of soybean stubbles were collected immediately after harvest (Soja 1) and four months after harvest (Soja 2). Corn crop residues were collected three months after harvest. Glyphosate evolution and total microbial activity (TMA) were monitored by release of 14C-CO2 and C-CO2 under laboratory conditions with two temperatures, 15 and...
Tipo: Journal article
Palavras-chave: Glyphosate; Stubbles; Mineralization; Non-tillage system; Total microbial activity.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100002

Algorithms of Expert Classification Applied in Quickbird Satellite Images for Land Use Mapping
Provedor de dados: 117
Autores: Perea,Alberto Jesús; Meroño,José Emilio; Aguilera,María Jesús.
The objective of this paper was the development of a methodology for the classification of digital aerial images, which, with the aid of object-based classification and the Normalized Difference Vegetation Index (NDVI), can quantify agricultural areas, by using algorithms of expert classification, with the aim of improving the final results of thematic classifications. QuickBird satellite images and data of 2532 plots in Hinojosa del Duque, Spain, were used to validate the different classifications, obtaining an overall classification accuracy of 91.9% and an excellent Kappa statistic (87.6%) for the algorithm of expert classification.
Tipo: Journal article
Palavras-chave: Expert classification; Vegetation index; Land cover; Object-based classification.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300013

Performance of Late Sown Wheat in Response to Foliar Application of Moringa oleifera Lam. Leaf Extract
Provedor de dados: 117
Autores: Yasmeen,Azra; Basra,Shahzad Maqsood Ahmed; Ahmad,Rashid; Wahid,Abdul.
A rise in temperature during early spring inducing early maturity is a key yield-reducing factor in late sown wheat (Triticum aestivum L.). Moringa oleifera Lam. leaves are rich in zeatin, a cytokinin that plays a role in delaying leaf senescence, in addition to other growth-enhancing compounds such as ascorbates, phenolics, and minerals. The objective of this study was to optimize dose and optimum growth stage for foliar-applied moringa leaf extract (MLE) and its role in delaying leaf senescence in late sown wheat. The wheat crop was shown on 16 December 2008; MLE (diluted 30 times) was applied at different growth stages from tillering to heading and heading alone and distilled water was sprayed as a control. All the MLE treatment results were better than...
Tipo: Journal article
Palavras-chave: Crop maturity; Seasonal leaf area duration; Late sowing; Wheat.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100015

Influence of Water Temperature and Heat Stress on Drinking Water Intake in Dairy Cows
Provedor de dados: 117
Autores: González Pereyra,Ana Valeria; Maldonado May,Verónica; Catracchia,Carlos Guillermo; Herrero,María Alejandra; Flores,Myriam Celina; Mazzini,Mariana.
Grazing animals are exposed to heat stress and there should be conditions to facilitate water intake. Three experiments were carried out to determine the relationship between water intake, water temperature, and heat stress for Holstein pastured dairy cows. Experiment 1: Drinking behavior of 13 cows was evaluated (for 3 consecutive days) and four time periods were established according to the temperature humidity index (THI): (H1:05:00 to 10:59 h, H2:11:00 to 16:59 h, H3:17:00 to 22:59 h, and H4:23:00 to 04:59 h). The highest mean percentage of drinking bouts (53.2%) was registered in H2 (THI: 74.91 to 83.95). Drinking bout means among time periods were different (p &lt; 0.05), thus showing that heat stress conditions influence drinking behavior....
Tipo: Journal article
Palavras-chave: Drinking behavior; Summer time; THI; Grazing dairy farms.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200017

Exploring the Potential use of Photo-Selective Nets for Fruit Growth Regulation in Apple
Provedor de dados: 117
Autores: Bastías,Richard M; Manfrini,Luigi; Corelli Grappadelli,Luca.
The effect of shading (i.e. reduction of sunlight availability) on fruit growth physiology has been widely studied in apple (Malus domestica Borkh.), but little knowledge exist about fruit growth responses to changes in the light spectrum. The aim of the present research was to study the effect of use of colored nets with differential sunlight transmission in the blue (B, 400-500 nm), red (R, 600-700 nm) and far-red (FR, 700-800 nm) spectra on apple fruit growth and physiological associated responses. Three year old 'Fuji' apple trees were covered with 40% photo-selective blue and red shade nets, 40% neutral grey shade net, and 20% neutral white net as control. Red and blue net reduced in the same proportion (27%) the photosynthetically active radiation...
Tipo: Journal article
Palavras-chave: Sunlight spectrum management; Fruit size; Photosynthesis; Morphogenesis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200010

Genetic Progress in Winter Wheat Cultivars released in Chile from 1920 to 2000
Provedor de dados: 117
Autores: Matus,Iván; Mellado,Mario; Pinares,Marcos; Madariaga,Ricardo; del Pozo,Alejandro.
Wheat (Triticum aestivum L.) is the major crop in terms of planted area and presents the largest distribution in the country covering a wide range of climatic regions. This study assesses the changes of various agronomic traits of winter wheat cultivars released in Chile between 1920 and 2000. A total of 117 winter accessions, representing 45 old and 72 modern cultivars were tested in a humid Mediterranean-type climate, with irrigation, in 2003. Old cultivars were those released before 1960 and modern ones were those released after 1960. Principal component (PC) analysis using 10 agronomic traits clearly separate modern from old cultivars of winter wheat. Comparing modern cultivars with old ones, plant height have been reduced by 25.6%, but others traits...
Tipo: Journal article
Palavras-chave: Genetic improvement; Grain quality; Mediterranean environment; Old and new cultivars; Principal components; Yield progress.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300001

Characterization of genetic coefficients of durum wheat (Triticum turgidumL. ssp. durum)'Llareta-INIA' and 'Corcolén-INIA'
Provedor de dados: 117
Autores: Garrido,Marco; Román,Luis; Silva,Paola; Castellaro,Giorgio; García de Cortázar,Víctor; Acevedo,Edmundo.
The genetic coefficients, representative of a crop, are necessary to use growth models; in many cases the range of the species is known, but there are no specific values for varieties. Durum wheat (Triticum turgidumL. ssp. durum)'Llareta-INIA' and 'Corcolén-INIA' were sown under irrigation in the experiment station Antumapu of the Universidad de Chile on 29 June 2007, 19 May 2009, and 15 June 2010 in order to determinate four genetic coefficients: developmental thermal time, phyllochron (PHLN), extinction coefficient (k), and radiation use efficiency (RUE), and to evaluate the performance of these coefficients. Thermal times to anthesis and from anthesis to physiological maturity were 652 and 541 °C d, respectively. Two PHLN values were found, 46.6 °C d...
Tipo: Journal article
Palavras-chave: Simulation; Thermal time; Radiation use efficiency; Extinction coefficient.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200002

Effect of the Irrigation Canal Network on Surface and Groundwater Interactions in the Lower Valley of the Cachapoal River, Chile
Provedor de dados: 117
Autores: Arumí,José Luis; Rivera,Diego; Holzapfel,Eduardo; Boochs,Peter; Billib,Max; Fernald,Alexander.
Agricultural production of high value crops in Chile's Central Valley is highly dependent on surface and groundwater resources. They are connected and together form an integrated hydrological system, the individual components of which have to be studied. This research is addressed to answering two questions: 1) to what extent do irrigation and canal seepage contribute to groundwater recharge and 2) what is the influence of the interactions between the Cachapoal River and ground water. The study was carried out from 2003 to 2007 in Peumo Valley (34.3° S, 71.3° W). In winter, the irrigation canal network intercepts and diverts surface runoff, which flows to flat areas and recharges groundwater. In summer, infiltration from the canals recharges the aquifer...
Tipo: Journal article
Palavras-chave: Agriculture; Chile; Groundwater; Irrigation seepage; MODFLOW; Surface water-groundwater interactions.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100002

Integrated use of Rhizobium leguminosarum, Plant Growth Promoting Rhizobacteria and Enriched Compost for Improving Growth, Nodulation and Yield of Lentil (Lens culinaris Medik.)
Provedor de dados: 117
Autores: Iqbal,Muhammad Asif; Khalid,Muhammad; Shahzad,Sher Muhammad; Ahmad,Maqshoof; Soleman,Nawaf; Akhtar,Naeem.
Maintenance of high bacterial population in the rhizosphere improves the efficiency of these organisms. This high bacterial population can be maintained by the application of enriched compost which supports their growth and activities. Thus integrated use of Rhizobium, plant growth promoting rhizobacteria (PGPR) containing 1-aminocyclopropane-1-carboxylate deaminase (ACC-deaminase) and P-enriched compost (PEC) could be highly effective for promoting growth, nodulation, and yield of lentil (Lens culinaris Medik.). A field study was conducted to evaluate the potential of Rhizobium, PGPR containing ACC-deaminase and PEC for promoting growth of lentil. For this study, the soil type was sandy clay loam soil having pH 7.6; EC (electrical conductivity) 2.8 dS...
Tipo: Journal article
Palavras-chave: Co-inoculation; Biological N fixation; Rhizobium; ACC-deaminase; P-enriched compost; Nodulation; Yield.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100017

Evaluation of the Resistance of Transgenic C5 Plum (Prunus domestica L.) against Four Chilean Plum Pox Virus Isolates through Micro-Grafting
Provedor de dados: 117
Autores: Wong,Wendy; Barba,Paola; Álvarez,Catalina; Castro,Álvaro; Acuña,Manuel; Zamora,Pablo; Rosales,Marlene; Dell´Orto,Paola; Moynihan,Michael R; Scorza,Ralph; Prieto,Humberto.
The transgenic plum (Prunus domestica L.) C5, in which the coat protein (CP) gene of the Plum pox virus (PPV) is inserted, represents a unique example of the use of genetic engineering for fruit crop improvement in Prunus spp. Field trials in Poland, Romania, and Spain have demonstrated resistance of C5 to several D and M strain PPV isolates. In Chile, the quarantine regulations for PPV and for genetically modified (GM) plants require that the testing of C5 for resistance to Chilean PPV isolates be done under controlled isolated conditions. To carry out these tests C5 shoots were multiplied in vitro and micro-grafted onto four Adesoto101 (Prunus insititia L.) rootstock populations that had been previously infected each with one of four Chilean PPV-Ds....
Tipo: Journal article
Palavras-chave: C5; Chilean isolates; Micro-grafting.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300004

Bio-Economic and Qualitative Impact of Reduced Herbicide use in Direct Seeded Fine Rice Through Multipurpose Tree Water Extracts
Provedor de dados: 117
Autores: Khaliq,Abdul; Matloob,Amar; Riaz,Yasir.
Weed control program should be environmentally benign and cost-effective so that reduced herbicide use can help meet these goals. Field trials were conducted to assess the bio-economic and qualitative impact of reduced doses (25 and 50% of label dose) of a postemergence pyrimidinyloxybenzoic acid herbicide (bispyribac-sodium) applied alone or in combination with multipurpose tree (eucalyptus Eucalyptus camaldulensis Dehnh., mango Mangifera indica L., and mulberry Morus alba L.) water extracts in direct seeded rice (Oryza sativa L.) fields. The label dose of bispyribac-sodium and penoxsulam along with weed control were included for comparison. Tank mixing of multipurpose tree water extracts with reduced herbicide doses accounted for &gt; 55% suppression in...
Tipo: Journal article
Palavras-chave: Reduced dose; Weed suppression; Yield; Kernel quality; Oryza sativa.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300008

Acute Contact Toxicity Test of Oxalic Acid on Honeybees in the Southwestern Zone of Uruguay
Provedor de dados: 117
Autores: Carrasco-Letelier,Leonidas; Mendoza,Yamandu; Ramallo,Gustavo.
This work studies the acute contact toxicity of oxalic acid (OA) on a honeybee polyhybrid subspecies (Apis mellifera), which is the dominant biotype in southwestern zone of Uruguay (SWZU) and the country's most important honey-producing region. We determined the mean lethal dose (LD50), as well as the no observed effect level (NOEL) and the lowest observed effect level (LOEL) values. We also estimated the total number of honeybees per hive in the test area. The aim was to assess the relationship between the maximum OA dose used in Uruguay (3.1 g OA per hive) and the toxicological parameters of honeybees from SWZU. The current dose of 3.1 g OA per hive corresponds to 132.8 OA per honeybee since determined NOEL is 400 OA per honeybee; our results indicate...
Tipo: Journal article
Palavras-chave: LD50; Uruguay.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200019

Paclobutrazol and Cytokinin to Produce Iris (Iris X hollandica Tub.) in Pots
Provedor de dados: 117
Autores: Francescangeli,Nora.
Because of the increasing and diversified demand for potted plants, there is interest in Argentina in commercial iris production (Iris x hollandica Tub.). Two experiments were performed at the Instituto Nacional de Tecnología Agropecuaria (INTA), San Pedro Agricultural Experimental Station (33º41’ S, 59º41’ W), Buenos Aires Province. The effects of increasing concentrations of paclobutrazol (PBZ) and combinations of PBZ and 6-benzylaminopurine (BA) were compared. Height, length of the cycle and rate of flowering were registered. Experiment 1: the bulbs were subjected to immersion in nine concentrations of PBZ: 0, 10, 20, 30, 40, 50, 60, 70 or 80 mg L-1 for 24 h. Experiment 2: the bulbs were immersed in three concentrations of PBZ: 0, 10 or 20 mg L-1 for 24...
Tipo: Journal article
Palavras-chave: Bulbous; Growth regulator; Height.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400005

Unconfined Aquifer Permeability near hand-dug Wells in the Coastal and Interior dryland of the Libertador General Bernardo O'Higgins Region, Chile
Provedor de dados: 117
Autores: Rupp,David E; Reckmann,Oscar; Vergara,Jorge; Uribe,Hamil; Selker,John S.
In the dryland of the Libertador General Bernardo O'Higgins Region in Chile, most farmers rely on wide and shallow hand-dug wells as their primary source of water during the dry summer. Few of these wells have sufficient yield for more than domestic use (human consumption, livestock, and irrigation of a subsistence garden). To more accurately assess available groundwater resources, saturated hydraulic conductivity (K) of aquifers in the eight counties that comprise this region’s dryland was estimated using evacuation and recovery tests in 353 hand-dug wells. K followed a log-normal distribution and ranged over nearly five orders of magnitude. County median K varied by a factor of 5 and a slight increasing K trend in the southward direction. In one northern...
Tipo: Journal article
Palavras-chave: Groundwater; Well recovery; Slug-test.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200012

Risk Preferences Estimation for Small Raspberry Producers in the Bío-Bío Region, Chile
Provedor de dados: 117
Autores: Toledo T,Roger; Engler P,Alejandra.
Decisions are strongly influenced by risk and risk preferences of decision makers; however, in Chile there are few studies in the agricultural sector focused on this topic. The present paper analyzes the risk preferences of small producers of raspberries (Rubus idaeus L.) and the production function associated with their production system in the Bio-Bio Region of Chile. Under a mean-variance approach, the estimation procedure uses a flexible utility function to incorporate a variety of risk preference alternatives. Three different estimation procedures were used: Least Squares Estimation, Seemingly Unrelated Regression and Full Information Maximum Likelihood, which revealed the same conclusions. Results showed that small farmers are risk averse (&amp;#947;...
Tipo: Journal article
Palavras-chave: Risk aversion; Mean-variance utility function; Production function.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200007

Simple Air Temperature Estimation Method from MODIS Satellite Images on a Regional Scale
Provedor de dados: 117
Autores: Flores P,Fabiola; Lillo S,Mario.
Agricultural studies on a regional scale about water balance and evapotranspiration estimation, among others, require estimating air temperature (Ta) spatial variation since the generally low density of weather stations does not allow obtaining such data for a specific area. The aim of this study was to estimate air temperature through atmospheric profiles provided by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on a regional level. One of the present-day methodologies estimates Ta through vertical temperature profiles, which is why modifications to this methodology were proposed for zoning, surface elevation, and pressure/altitude ratios. By applying this new methodology, better Ta estimates were obtained by replacing the MODIS sensor...
Tipo: Journal article
Palavras-chave: MODIS; Atmospheric profile; Digital elevation model.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300011

Condensed Tannin Concentrations of Three Lotus Species Grown in Different Environments
Provedor de dados: 117
Autores: Acuña,Hernán; Concha,Alex; Figueroa,Marcos.
Condensed tannins (CT) present in Lotus spp., depending on their concentration in the plant, can prevent bloating and improve protein absorption in ruminants. With the objective to know the variability of this characteristic, the CT concentration (% dry matter basis) was determined by the butanol-HCl procedure in 13 cultivars of Lotus corniculatus L. (Lc) introduced from North and South America and Oceania, 11 accessions of Lotus tenuis Waldst. &amp;amp; Kit. ex Willd. (Lt), and 22 accessions of Lotus uliginosus Schkuhr (Lu) collected in Chile, from 32° to 38° S and 36° to 46° S, respectively. The field experiments, with two randomized complete blocks, were established in autumn 1998, in five different environments in the central-southern zone of Chile...
Tipo: Journal article
Palavras-chave: Condensed tannins.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100004

Biological Fixation of N2 in Mono and Polyspecific Legume Pasture in the Humid Mediterranean Zone of Chile
Provedor de dados: 117
Autores: Espinoza,Soledad; Ovalle,Carlos; del Pozo,Alejandro; Zagal,Erik; Urquiaga,Segundo.
Despite annual legume pasture are of great importance for dryland agricultural systems in Mediterranean environments, there are few studies of N2 biological fixation (NBF) reported in Chile. In this study the NBF of four annual legume species: subterranean clover (Trifolium subterraneum L.), yellow serradella (Ornithopus compressus L.), arrow-leaf clover (T. vesiculosum L.), and crimson clover (T. incarnatum L.) (Experiment 1), as well as seven mixtures of these species (Experiment 2) were assessed. The NBF was measured by the 15N natural abundance technique. The objective was to determine NBF in the legume species and in distinct mixtures used. The study was carried out in an Andisol of the Andean Precordillera located in the humid Mediterranean zone of...
Tipo: Journal article
Palavras-chave: Natural abundance of 15N; Mediterranean pastures; Volcanic soil.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100016

Symptoms and Sensitivity to Chilling Injury of Cantaloupe Melons during Postharvest
Provedor de dados: 117
Autores: Krarup,Christian; Tohá,Jaime; González,Rodrigo.
The nature and development of specific symptoms of chilling injury (CI) and the variation in sensitivity to the disorder of different cultivars of cantaloupe melons (Cucumis melo L. subsp. melo var. cantalupensis Naudin) was assessed during two seasons. Twenty-three cultivars of the Eastern Shipper (2), Western Shipper (13) and Galia (8) types were grown in a semiarid environment in Curacaví (33º27’ S, 70º38’ W), Chile, using common cultural practices. Fruits were harvested at the half-slip stage, except Galia (3/5 color), graded ,washed, and stored for 18 days at 0 ºC, with an additional 3 days at 20 ºC. Symptoms of CI appeared with varying intensity in almost all cultivars and were generally similar. Symptoms developed progressively: surface...
Tipo: Journal article
Palavras-chave: Cultivars; Storage; Symptom progression; Weight loss; Soluble solids.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200001

Polyphenol content and antioxidant activity of maqui (Aristotelia chilensis Molina Stuntz) during fruit development and maturation in Central Chile
Provedor de dados: 117
Maqui (Aristotelia chilensis Molina Stuntz, Elaeocarpaceae) is a Chilean native species which produces small berries that are mainly collected from the wild. The health benefits of maqui fruit are attributed to their high polyphenol content as well as their wide variety of anthocyanins and flavonols. One of the main factors that affect the polyphenol content in fruit is the maturity stage at harvest. The objective of this study was to determine total phenol and total anthocyanin content and antioxidant activity (by ferric reducing ability of plasma FRAP assay) of maqui fruits harvested at different fruit maturity stages from two wild populations located in Central Chile. Each maturity stage was determined by days from fruit set, berry size, and soluble...
Tipo: Journal article
Palavras-chave: FRAP; Maturity stages; Ripening; Total anthocyanins; Total phenols.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400019

Design and Management of Irrigation Systems
Provedor de dados: 117
Autores: Holzapfel,Eduardo A; Pannunzio,Alejandro; Lorite,Ignacio; Silva de Oliveira,Aureo; Farkas,István.
Irrigation systems should be a relevant agent to give solutions to the increasing demand of food, and to the development, sustainability and productivity of the agricultural sector. The design, managing, and operation of irrigation systems are crucial factors to achieve an efficient use of the water resources and the success in the production of crops and orchards. The aim of this paper is to analyze knowledge and investigations that enable to identify the principal criteria and processes that allow improving the design and managing of the irrigation systems, based on the basic concept that they facilitate to develop agriculture more efficient and sustainable. The design and managing of irrigation systems must have its base in criteria that are relevant,...
Tipo: Journal article
Palavras-chave: Irrigation; Design; Water management; Operation systems.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500003

Visualizing Adaptation of Genotypes with a Ternary Plot
Provedor de dados: 117
Autores: Kozak,Marcin.
Adaptation can be studied through various methods, some of which are based on adaptation or stability measures while others on complex models and graphs. In this adaptation measure based on quantiles is presented; the measure is three-dimensional and can be pictured with a ternary (trilinear) plot. A simple algorithm for constructing such a plot is presented and the interpretation of the plot is discussed. By means of this graphical tool one can picture and interpret the specific and wide adaptation of genotypes to environments, offering complementary information to that of other methods of analyzing genotype-by-environment data.
Tipo: Journal article
Palavras-chave: Adaptability; Wide and specific adaptation; Quantiles; Trilinear plot; Visualization.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400010

Methods to Estimate Lettuce Evapotranspiration in Greenhouse Conditions in the Central Zone of Chile
Provedor de dados: 117
Autores: Casanova P,Manuel; Messing,Ingmar; Joel,Abraham; Cañete M,Alberto.
This study evaluates five methods to estimate crop evapotranspiration in greenhouse conditions. It compares their performance in relation to the evapotranspiration directly determined from water balance measurements (ETlys) in an irrigated lettuce (Lactuca sativa L.) crop during 9 weeks. Daily values of the reference evapotranspiration (ETo) from Class A pan (CAP), Piche atmometers (ATM), Andersson evaporimeters (ANE), FAO-Radiation (FRE) and FAO-Penman-Monteith (PME) equations were compared. The methods showed similar temporal variations but at different ranges as follows: ANE &lt; CAP &lt; FRE &lt; PME &lt; ATM. Furthemore, ETo had a clear correlation with solar radiation. Crop coefficients (Kc = ETlys/ETo) varied somewhat amongst the methods, but trends...
Tipo: Journal article
Palavras-chave: Evapotranspiration; Greenhouse; Lettuce; Lysimeter.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100008

Insecticidal Activity of the Essential Oil Isolated from Azilia eryngioides (Pau) Hedge et Lamond Against Two Beetle Pests
Provedor de dados: 117
Autores: Ebadollah,Asgar; Mahboubi,Mohaddese.
A large number of plant essential oils have been used against diverse insect pests since they, unlike conventional pesticides, present no risk to humans and the environment. This study was conducted to determine the toxicity of Azilia eryngioides (Pau) Hedge et Lamond (Apiaceae) essential oil against 1- to 7-d-old Sitophilus granarius (L.) (Curculionidae) and Tribolium castaneum (Herbst) (Tenebrionidae) adults. The essential oil was obtained from aerial parts of the plant using a Clevenger apparatus and analyzed by gas chromatography and mass spectrometry. The major constituents of the oil were &amp;#945;-Pinene and bornyl acetate. Fumigation bioassays revealed that A. eryngioides oil had a strong insecticidal activity on adult test insects that were...
Tipo: Journal article
Palavras-chave: Botanical insecticide; Apiaceae; Fumigant toxicity.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300010

Beef Consumer Preferences in Chile: Importance of Quality Attribute Differentiators on the Purchase Decision
Provedor de dados: 117
Autores: Villalobos,Pablo; Padilla,Carlos; Ponce,Cristian; Rojas,Álvaro.
Agrifood markets worldwide have focused on searching for new quality attribute differentiators, which capture the attention of consumers and meet their needs. The purpose of this research was to determine the importance of a set of quality attribute differentiators associated with a beef cut on the choice behavior of the Chilean consumer. The evaluated differentiating characteristics were: price, origin, production method, and quality assurance. A total of 750 subjects were surveyed in the following cities: Talca, Rancagua, and Santiago. Conjoint analysis was carried out to estimate the impact of the assessed attributes on the purchase decision of the consumers polled. Findings point out that the quality attribute differentiators significantly influence...
Tipo: Journal article
Palavras-chave: Conjoint analysis; Country of origin; Animal welfare; Quality assurance; Differentiation; Marketing.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100009

Inheritance of Seed Weight in Large-Seed Grass Pea Lathyrus sativus L
Provedor de dados: 117
Autores: Mera,Mario.
Mean seed weight (MSW) is a relevant trait in grass pea (Lathyrus sativus L.) commercialization because large grains are preferred in Western markets. Extending the knowledge on its mode of inheritance among large-seeded types would be useful in breeding programs, and therefore it was the objective of this work. A broad range of MSW is found in grass pea, starting at about 30 mg. Three lines (LS-97, LS-8, and LS-2026) within the large-seeded group but with significantly different MSW (179, 360 and 470 mg, respectively), were crossed in a complete diallel. Part of the F1 seed was sown and the remainder was stored. F1 plants from each cross were allowed to produce F2 seed and some were backcrossed to their respective parents. Parents, F1, F2, and backcross...
Tipo: Journal article
Palavras-chave: Grass pea; Heritability; Cool-season grain legumes.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300002

Evaluation of the Impact of Climatic Change on the Economic Value of Land in Agricultural Systems in Chile
Provedor de dados: 117
Autores: González U,Jorge ; Velasco H,Roberto .
Climatic change will affect crop yields and management. By the year 2050, the mean temperature could increase by 1.5 ºC; and by the year 2100 between 1.0 to 3.5 ºC. There are few studies on this subject in Chile. At the international level, estimated climatic changes in temperate and tropical zones could negatively affect wheat (Triticum vulgare L.) and corn (Zea mays L.) production, as examples. The objective of this study was to determine the relationship between agricultural systems and climatic change by using the Ricardian Method. Specific objectives were to evaluate and quantify the relationship of climatic variables (precipitation and temperature) with economic variables under several realities of farms, to simulate the impact of scenarios of...
Tipo: Journal article
Palavras-chave: Climate change; Ricardian method; Land productivity; Land value; Policy of adaptation.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100006

Perennial grasses traits as functional markers of grazing intensity in basaltic grasslands of Uruguay
Provedor de dados: 117
Autores: Jaurena,Martin; Lezama,Felipe; Cruz,Pablo.
Natural grasslands in the basaltic region of Uruguay are threatened by an increase in stocking rates and changes in land use. To assess the effect of grazing intensification, plant functional types are proposed as simple tools to aid the monitoring and management of vegetation. In the present study we evaluated the effect of stocking rate increase at community level taking into account plant traits of 23 dominant perennial grass species. In order to identify plant functional types, we determined the grazing response in an experiment with two wethers stocking rates (0.78 and 1.56 livestock units ha-1) quantifying species cover and traits values. Leaf dry matter content (LDMC) and specific leaf area (SLA) were the traits that best described the perennial...
Tipo: Journal article
Palavras-chave: Natural grasslands; Diagnosis; Management; Stocking rate.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400013

Importance of Ionic and Osmotic Components of Salt Stress on the Germination of Four Quinua (Chenopodium quinoa Willd.) Selections
Provedor de dados: 117
Autores: Delatorre-Herrera,José; Pinto,Manuel.
The influence of the components of saline stress (osmotic and ionic factors) were evaluated during the germination of four quinua (Chenopodium quinoa Willd.) selections in Chile, two collected in the arid northern highland region with saline soils (Amarilla and Roja) and the other two from the rainy southern region with non-saline soils (Hueque and Pucura). The seeds were treated with different saline concentrations (0, 0.2, 0.4, 0.8 and 1.2 M NaCl). Germination kinetics shows that the control treatments of the four selections reach 100% germination. With application of 0.4 M NaCl (LD50max) germination was reduced by 53% in the Amarilla selection and 89.9% in Hueque. The germination rate was lower for the seeds from non-saline areas, which reached...
Tipo: Journal article
Palavras-chave: Salinity; Imbibition; Seeds; NaCl; Altiplano; Desert.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400001

Biological characteristics of Palmistichus elaeisis Delvare &amp;amp; LaSalle (Hymenoptera: Eulophidae) on refrigerated pupae of Anticarsia gemmatalis Hubner (Lepidoptera: Noctuidae)
Provedor de dados: 117
Autores: Pereira,Fabricio Fagundes; Cola Zanuncio,José; Oliveira Kassab,Samir; Pastori,Patrik Luiz; Hidalgo Barbosa,Rogério; Rossoni,Camila.
Mass rearing of parasitoids is a fundamental step for biological control programs. The biological characteristics of Palmistichus elaeisis Delvare &amp;amp; LaSalle (Hymenoptera: Eulophidae) were evaluated in pupae of Anticarsia gemmatalis Hubner (Lepidoptera: Noctuidae) stored at low temperatures. Twenty four hours-old pupae of A. gemmatalis were stored at 12 °C for 0, 1, 3, 6, 9, and 12 d and then exposed to parasitism by P. elaeisis females. The life span of P. elaeisis was affected and ranged from 19 to 24 d on the pupae of the host. Parasitism reached 100% of the host pupae after storage in all periods at 12 °C, and adults emerged from 20.00 to 54.54% of them. The progeny of P. elaeisis ranged from 71 to 198 and had an inverse relationship with the...
Tipo: Journal article
Palavras-chave: Biological control; Parasitism; Parasitoid rearing; Temperature.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200005

Effect of Quail Litter Biochar on Productivity of Four New Physic Nut Varieties Planted in Cadmium-Contaminated Soil
Provedor de dados: 117
Autores: Suppadit,Tawadchai; Kitikoon,Viroj; Phubphol,Anucha; Neumnoi,Penthip.
Biochar can improve soil structure and water retention, enhance nutrient availability and retention, ameliorate acidity, and reduce heavy metal toxicity to plant roots. In this study, a basin experiment was conducted to investigate the effects of quail litter biochar (QLB) on the availability of Cd to physic nut (Jatropha curcas L.) plants. QLB was applied to the soil in which four new physic nut varieties (Takfa, Doi Saket, Lao, and Rayong) in factorial combinations at four levels (0, 5, 10, and 15 g kg-1 soil) to soil that contained 60.8 mg Cd kg-1. After transplanting plant height and canopy radius were measured every 2-mo and the number of leaves and branches at 6-mo, while yield components and Cd residues were measured at 8-mo intervals. The...
Tipo: Journal article
Palavras-chave: Adsorption; Heavy metal; Phytoremediation; Plant production; Pyrolysis; Soil amendment.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100020

Carbonic Anhydrase and Zinc in Plant Physiology
Provedor de dados: 117
Autores: Escudero-Almanza,Dalila Jacqueline; Ojeda-Barrios,Dámaris Leopoldina; Hernández-Rodríguez,Ofelia Adriana; Sánchez Chávez,Esteban; Ruíz-Anchondo,Teresita; Sida-Arreola,Juan Pedro.
Carbonic anhydrase (CA) (EC: 2.4.1.1) catalyzes the rapid conversion of carbon dioxide plus water into a proton and the bicarbonate ion (HCO3-) that can be found in prokaryotes and higher organisms; it is represented by four different families. Carbonic anhydrase is a metalloenzyme that requires Zn as a cofactor and is involved in diverse biological processes including pH regulation, CO2 transfer, ionic exchange, respiration, CO2 photosynthetic fixation, and stomatal closure. Therefore, the review includes relevant aspects about CA morphology, oligomerization, and structural differences in the active site. On the other hand, we consider the general characteristics of Zn, its geometry, reactions, and physiology. We then consider the CA catalysis mechanism...
Tipo: Journal article
Palavras-chave: Cofactor; Metal ion catalysis; Metalloenzyme; Zinc deficiency; CO2 transfer.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100022

Characterization of Sugars and Organic Acids in Commercial Varieties of Table Grapes
Provedor de dados: 117
Autores: Muñoz-Robredo,Pablo; Robledo,Paula; Manríquez,Daniel; Molina,Rosa; Defilippi,Bruno G.
Flavor composition has been defined as a complex attribute of fruit quality, in which the mix of sugars, acids and volatiles play a primary role. In table grapes (Vitis vinifera L.), sweetness and sourness are the most important flavor attributes for fresh consumption. However, most of the studies available have been performed on wine grapes, which are grown, cultured and processed differently to table grapes. Therefore, the objective of this work was to characterize the changes in sugars and organic acids during the development of ‘Thompson Seedless’, ‘Red Globe’ and ‘Crimson Seedless’ grown under the same agroclimatic conditions. Each variety was sampled weekly from 2 wk before véraison until commercial harvest. Sugars and organic acids were quantified...
Tipo: Journal article
Palavras-chave: Fructose; Glucose tartaric acid malic acid chromatography development stages HPLC.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300017

Comparison of Pollen Production and Quality Characteristics of Cultivated and Wild Almond Species
Provedor de dados: 117
Autores: Bayazit,Safder; Califkan,Oguzhan; Imrak,Burhanettin.
There are several wild almond species in Turkey included Amygdalus orientalis (Mill.), Amygdalus turcomanica (Lincz.), Amygdalus fenzliana (Fritsch) Lipsky, Amygdalus trichamygdalus (Hand.-Mazz.) Woronow, Amygdalus arabica (Olivier), and Amygdalus webbii (Spach). These species offer a great value for the almond improvement; we studied the pollen viability, germination ratio and pollen yield for seven genotypes of A. orientalis, seven genotypes of A. turcomanica all growing under natural conditions in Southeastern Anatolia (Gaziantep and §anliurfa provinces, Turkey). Almond cultivars (Prunus dulcis [Mill.] D.A. Webb) obtained from Pozanti Agricultural Experimental Station, Cukurova University, were also used in the experiment. The pollen viabilities of...
Tipo: Journal article
Palavras-chave: Pollen.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400006

Chemical Composition and Allelopathyc Activity of Essential Oil of Lippia sidoides Cham
Provedor de dados: 117
Autores: Araújo Marco,Cláudia; Teixeira,Erlan; Simplício,Antonio; Oliveira,Carlos; Costa,José; Feitosa,José.
The allelopathy is a process for which products of the secondary metabolism, as terpenes phenolic, of a certain vegetal intervene significantly, generally of antagonistic form, in the development of other species of plants. The objective of this work was to chemically characterize the essential oil of Lippia sidoides Cham. growing in the Cariri cearense region, Brazil, and evaluate the allelopathyc effect of this oil on the germination of lettuce (Lactuca sativa L.), arugula (Eruca sativa Mill.), and cauliflower (Brassica oleracea L.), in pre-plantation application. The monoterpene thymol (84.90%) has been identified as the principal constituent in the essential oil. The experiment was done in randomized complete block, in 4 x 3 factorial; being used four...
Tipo: Journal article
Palavras-chave: Allelopathy; Plant oil.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100025

Preference of Quinoa Moth: Eurysacca Melanocampta Meyrick (Lepidoptera: Gelechiidae) for Two Varieties of Quinoa (Chenopodium quinoa Willd.) in Olfactometry Assays
Provedor de dados: 117
Autores: Costa,Juan  F; Cosio,Walter  ; Cardenas,Maritza  ; Yábar,Erick  ; Gianoli,Ernesto  .
Insects are attracted to plants by visual and olfactory cues. The quinoa moth, Eurysacca melanocampta Meyrick (Lepidoptera: Gelechiidae), is the main insect pest of the quinoa crop, Chenopodium quinoa Willd. (Chenopodiales: Chenopodiaceae), in the southern Peruvian Andes, causing grain yield losses. The aim of this study was to investigate the behavioural response of adult quinoa moths to olfactory stimuli. Specifically, the objectives of this study were: 1) to determine the capacity of E. melanocampta adults of searching for quinoa plants using plant olfactory cues; 2) to determine the preference of E. melanocampta females for the odours derived from two varieties of quinoa: Amarilla de Marangani and Blanca de Junín; and 3) to assess the attraction of...
Tipo: Journal article
Palavras-chave: Attraction; Chenopodiaceae; Gelechiidae; Searching; Olfactometry; Quinoa.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100009

Lotus tenuis Seedling Establishment and Biomass Production in Flooding Pampa Grasslands (Buenos Aires , Argentina)
Provedor de dados: 117
Autores: Vignolio,Osvaldo R; Fernández,Osvaldo N.
Biomass and plant density of Lotus tenuis Waldst. &amp;amp; Kit. ex Willd. have been reported in decreasing in grasslands and pastures. Our objective was to determine if L. tenuis biomass and plant density can be increased in grassland through seed addition. Two separated experiments under cattle grazing exclusion were conducted in three paddocks of a Flooding Pampa grassland. The first experiment was from autumn 2004 to autumn 2006 and the second from autumn 2005 to autumn 2007. Different L. tenuis seed additions (0, 57, 229, 917 and 1833 seeds m-²) were broadcast into experimental plots. In the second experiment, besides seed additions there was a reseeding of approximately 900 seed m-² from seed rain produced by plants of grassland. Seed density...
Tipo: Journal article
Palavras-chave: Legume; Forage quality; Population attributes; Seedling mortality; Seed addition.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100012

Effects of Soil Aluminum on Early Arbuscular Mycorrhizal Colonization of Wheat an Barley Cultivars Growing in an Andisol
Provedor de dados: 117
Autores: Seguel,Alex; Medina,Jorge; Rubio,Rosa; Cornejo,Pablo; Borie,Fernando.
Aluminum phytotoxicity in acid soils is an important environmental stress that negatively affects crop production, but arbuscular mycorrhizal (AM) fungi performance would allow plants to better withstand this environmental condition. This study aimed to analyze the effect of soil Al on early AM colonization of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) cultivars. Near-isogenic Crac, Invento, and Porfiado wheat cultivars and Sebastián and Aurora barley cultivars were sown in pots in an acid soil at three Al saturation levels (60, 34, and 11%). At 20 d after sowing (DAS) 'Crac' presented higher AM colonization (27%) than other cultivars. However, 'Invento' had the fastest colonization at 41 DAS, which was inhibited in short term at lower...
Tipo: Journal article
Palavras-chave: Acid soils; Arbuscular mycorrhizal propagules; Cereal crop; Soil aluminum saturation.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300022

Toxicity of Boldo Peumus boldus Molina for Sitophilus zeamais Motschulsky and Tribolium castaneum Herbst
Provedor de dados: 117
Autores: Ortiz U,Margarita; Silva A,Gonzalo; Tapia V,Maritza; Rodriguez M,J. Concepción; Lagunes T,Angel; Santillán-Ortega,Candelario; Robles-Bermúdez,Agustín; Aguilar-Medel,Sotero.
The maize weevil (Sitophilus zeamais Motschulsky) and the red flour beetle (Tribolium castaneum Herbst) are two key pests of stored-grain products worldwide. The insecticidal activity of boldo (Peumus boldus Molina) powder, liquid ethanolic and hexanic extracts against S. zeamais and T. castaneum were evaluated under laboratory conditions. The evaluated variables were mortality, emergence of adult insects (F1), and grain weight loss. The experimental design was completely randomized. The mortality in S. zeamais was 100% even at the lowest powder concentration (0.5% w/w), whereas emergence of F1 adult insects was 0% and grain weight loss was &lt; 0.08%. For T. castaneum, only 8 and 16% w/w powder concentrations reached 100% mortality. The liquid ethanolic...
Tipo: Journal article
Palavras-chave: Botanical insecticides; Stored grains; Maize weevil; Red flour beetle.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300007

Postharvest Behavior of Highbush Blueberry Fruits cv. O’Neal Cultivated with Different Organic Fertilization Treatments
Provedor de dados: 117
Autores: Echeverría V,Graciela; Cañumir V,Juan; Serri G,Humberto.
Considering the increasing demand for organic products and the fact that Chile is far from export markets, fresh fruits of highbush blueberry (Vaccinium corymbosum L. x Vaccinium darrowii Camp) from organic fertilization were stored at 3 ºC and 90% RH for 30 d in modified atmosphere (MA) and conventional atmosphere (CA) with the objective of studying the effect of organic fertilization treatments in postharvest behavior. The variables, water content, weight loss, diameter loss, soluble solids, titratable acidity, pH, and presence of pathogens were evaluated during three periods; with a divided plot factorial arrangement experimental design. Results were submitted to variance analysis, and Tukey test (P &amp;#8804; 0.05) was applied when significant...
Tipo: Journal article
Palavras-chave: Organic fertilization; Modified atmosphere.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300012

Cold tolerance evaluation in Chilean rice genotypes at the germination stage
Provedor de dados: 117
Autores: Donoso Ñanculao,Gabriel; Paredes Cárcamo,Mario; Arbiza de los Santos,Oscar; Becerra Velásquez,Viviana.
Low temperature is the most important abiotic stress affecting rice (Oryza sativa L.) yield in Chile. Rice in Chile is usually planted when the minimum air temperatures are below 12 °C. This temperature is lower than the optimum needed for normal rice germination. Therefore, the aim of this study was to evaluate cold tolerance in 20 experimental lines from the Rice Breeding Program of the Instituto de Investigaciones Agropecuarias (INIA), Chile, at the germination stage. Coleoptile length reduction (CRED), coleoptile length after cold treatment (CLEN), coleoptile length recovery (CREC), and coleoptile regrowth (CREG) were evaluated at 13 °C for 4 d using 'Diamante-INIA' as the cold-tolerant control. To find genotypes with cold tolerance (low CRED value and...
Tipo: Journal article
Palavras-chave: Low temperatures; Coleoptile length; Experimental lines.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100001

Evaluation of a model to Simulate Net Radiation Over a Vineyar cv. Cabernet Sauvignon
Provedor de dados: 117
Autores: Carrasco,Marcos; Ortega-Farías,Samuel.
Net radiation (Rn) is the main energy balance component controlling evaporation and transpiration processes. In this regard, this study evaluated two models to estimate Rno above a commercial vineyard (Vitis vinifera cv. Cabernet Sauvignon) located in Pencahue Valley, Maule Region (35º22’ S; 71°47’ Wl; 75 m.a.s.l.). An automatic meteorological station (AMS) was installed in the central part of the vineyard and used to measure Rn, solar radiation (Rsi), air temperature (Ta), canopy temperature (Tf) and relative humidity (RH). On a 30 min interval, results indicated that model Rne1 (assuming Ta &amp;#8800; Tf) and model Rne2 (assuming Ta = Tf ) were able to estimate Rn with a mean absolute error (MAE) of less than 40 W m-2 and root mean square error (RMSE)...
Tipo: Journal article
Palavras-chave: Atmospheric emissivity; Terrestrial radiation; Atmospheric radiation; Energy balance.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200005

Seed softening patterns of forage legumes in a temperate/subtropical environment in Uruguay
Provedor de dados: 117
Autores: Do Canto,Javier; Reyno,Rafael; Real,Daniel; Revell,Clinton.
Few studies have been conducted in annual and perennial forage legumes to investigate the development of hardseededness and the subsequent pattern of seed softening in temperate and subtropical regions of South America. Experiments were conducted during 2007 and 2008 in central Uruguay to follow the pattern of seed softening in 35 annual and perennial forage legumes, including three native species of Uruguay and five commercial cultivars. Newly ripened seeds of each plant material were placed in mesh packets on the soil surface in mid-summer. Samples were recovered monthly for germination tests and the proportion of residual hard seeds determined. The native species Adesmia bicolor (Poir.) DC., Adesmia securigerifolia Herter, and Ornithopus micranthus...
Tipo: Journal article
Palavras-chave: Hard seeds; Adesmia; Ornithopus; Trifolium; Lotus.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100006

Mathematical Modeling in the Estimation of Pepper (Capsicum annuum L.) Fruit Volume
Provedor de dados: 117
Autores: Kadri Bozokalfa,M; Kilic,Murat.
Peppers (Capsicum annuum L.) are an important horticultural crop and are used fresh and processed. Fruit size estimation is used to describe the fruit’s growth curve, monitor individual plant growth, predict yield, and conduct physiological studies. Water displacement techniques are used to determine fruit volume, but these are time-consuming and impractical under field conditions. The aim of this study was to devise a mathematical model to analytically determine the non-destructive pepper fruit volume. Fruit volume was described as a dependent variable, while length, weight, and diameter were independent variables in the model which was formulated as Yi = 19.226859 + 0.139562 Xi - 0.256142 Zi + 1.429122 Ti, where Yi = fruit volume (cm³), and Xi, Zi, and...
Tipo: Journal article
Palavras-chave: Fruit growth; Modeling applications; Pepper fruit; Predicting; Water displacement.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400013

Improving meat quality through natural antioxidants
Provedor de dados: 117
Autores: Velasco,Valeria; Williams,Pamela.
Nowadays, consumers are demanding more natural foods, obliging the industry to include natural antioxidants in foods. Natural antioxidants have been used instead of synthetic antioxidants to retard lipid oxidation in foods to improve their quality and nutritional value. This review discusses some aspects of recent research on antioxidant activity of plant extracts and natural compounds to improve meat quality. Many herbs, spices, and their extracts have been reported as having high antioxidant capacity, such as some plants of the Lamiaceae family, e.g., oregano (Origanum vulgare L.), rosemary (Rosmarinus officinalis L.), and sage (Salvia officinalis L.). The antioxidant activity of these plants is attributed to their phenolic compound content, which...
Tipo: Journal article
Palavras-chave: Antioxidant activity; Essential oils; Phenolic compounds; Meat quality.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200017

Spatial Analysis of Infiltration in an Oxisol of the Eastern Plains of Colombia
Provedor de dados: 117
Autores: Orjuela-Matta,Helber Milton; Rubiano Sanabria,Yolanda; Camacho-Tamayo,Jesus H.
Studies that involve soil attributes variability help the analysis of the behavior of hydrophysical attributes in space, to support the decision-making process within the conception of precision agriculture. The aim of the present paper was to characterize the spatial variability of the surface infiltration and its relation to some soil physical attributes. The sampling was done with a rectangular mesh of 64 points with perpendicular distances of 52 m x 45 m between sampling points. The attributes studied were bulk density, contents of sand, silt and clay, soil moisture, cumulative infiltration, basic infiltration, sorptivity, and saturated hydraulic conductivity (Ks). Data were analyzed using descriptive statistics and geostatistics, identifying the...
Tipo: Journal article
Palavras-chave: Geostatistics; Hydraulic conductivity; Infiltration; Sorptivity.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300015

Furrow Irrigation Management and Design Criteria Using Efficiency Parameters and Simulation Models
Provedor de dados: 117
Autores: Holzapfel,Eduardo A.; Leiva,Carlos; Mariño,Miguel A.; Paredes,Jerónimo; Arumí,José L.; Billib,Max.
This study analyzes the relationship between the variables of furrow irrigation and the irrigation performance parameters, crop yield, and deep percolation as a basis for furrow irrigation design and management. Application efficiency (AE), requirement efficiency (RE), requirement distribution efficiency (RDE), total distribution efficiency (TDE), and furrow irrigation management, operation, and design variables (inflow discharge, furrow length, and irrigation cutoff time) were correlated. The relationship between performance irrigation parameters and relative yield was also examined. In addition, environmental aspects related to leaching and runoff were also presented for each of the parameters. Study results indicate that increasing the length of the...
Tipo: Journal article
Palavras-chave: Furrow; Irrigation; Performance parameters; Model; Yield; Leaching.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200012

Agricultural Labor Demand in Chile: A Cointegration Approach
Provedor de dados: 117
Autores: Saens N,Rodrigo; Lobos A,Germán; Rivera A,Edinson.
International evidence shows that the positive relationship between product and agricultural labor has weakened during the last 30 years, especially in emergent economies. Chilean agriculture has not been left out of this phenomenon The main purpose of this reseach was to estimate the causality relationships that govern the product, employment and salaries in the Chilean silviculture-agricultural-livestock sector, using a cointegration approach. Quarterly data from the 1996-2005 period were employed to estimate agricultural labor demand. A Cobb-Douglas agricultural production function was employed and from it were derived the minimum cost function and the labor demand as bases of this study; the latter was approximated log-linearly to find different...
Tipo: Journal article
Palavras-chave: Agricultural labor; Cobb-Douglas; Employment-product elasticity; Employment-salary elasticity.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400009

Effect of Including Extruded, Rolled or Ground Corn in Dairy Cow Diets Based on Direct Cut Grass Silage
Provedor de dados: 117
Autores: Alvarado G,Christian; Anrique G,René; Navarrete Q,Soledad.
A study was conducted to determine the effect of corn (Zea mays L.) grain processing on intake, digestibility of nutrients and milk production and composition. The effect of extrusion on nutrient digestibility was evaluated in trial 1, using ground corn as a control. In trial 2, the effect of extrusion on intake was evaluated, comparing extruded corn of two densities (357 and 308 g L-1) with rolled corn (507 g L-1) as a control. In trial 3, the effects of extrusion on milk production, digestibility and intake were evaluated; using steam rolled corn and ground corn as controls. No effects on dry matter and metabolizable energy intakes due to differences in the extruded corn grains were observed. Digestibility of dry matter, organic matter, crude protein,...
Tipo: Journal article
Palavras-chave: Extruded corn; Intake; Digestibility; Milk production.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300008

Advances in Apple Transformation Technology to Confer Resistance to Fungal Diseases in Apple Crops: A Chilean Perspective
Provedor de dados: 117
Autores: Polanco,Víctor; Paredes,Mario; Becerra,Viviana; Pérez,Eduardo.
Apple (Malus domestica Borkh.) is one of the most consumed fruit in the world. Genetic transformation is a key process to sustain this demand by permitting the potential enhancement of existing cultivars as well as the development of new cultivars resistant to pests, diseases, and storage problems that occur in the major production areas. This review summarizes the advances of genetic engineering applied to the development of resistant apple cultivars to fungus disease, with particular attention in the generation of apples resistant to Venturia inaequalis (Cooke) G.Winter, the main phytosanitary problem that affects apple crops in Chile.
Tipo: Journal article
Palavras-chave: Apple; Fungal disease; Transgenic; Cisgenesis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200013

Glyphosate Use in Forest Plantations
Provedor de dados: 117
Autores: Kogan,Marcelo; Alister,Claudio.
Under Chilean conditions the lack of weed control at forest tree establishment results in an average of at least 60% less biomass accumulation during the first year of growth of radiate pine or eucaliptus, and glyphosate offers a series of advantages in forestry weed management because its activity in both herbaceous weed groups, monocots and dicots, as well as annuals, biennials and perennials. Also, its efficacy in woody undesirable vegetation makes glyphosate a very important herbicide that can be applied to control herbaceous and woody weeds as pre-planting and during the second or third years of trees growth as strip applications. The aim of this review is to discuss the main uses of glyphosate in reforestation worldwide, during the first 2 yr after...
Tipo: Journal article
Palavras-chave: Pine; Eucalyptus; Rainfastness; Woody plants.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400017

Exogenous Application of Polyamines Improves Germination and Early Seedling Growth of Hot Pepper
Provedor de dados: 117
Autores: Aziz Khan,Hammad; Ziaf,Khurram; Amjad,Muhammad; Iqbal,Qumer.
Polyamines are low molecular weight organic compounds involved in diverse range of biological processes in all living organisms. Seed priming is a technique that improves seed performance by rapid and uniform germination with normal and vigorous seedlings. A laboratory study was performed to explore the benefits of seed priming with polyamines on seed germination and seedling growth of hot pepper (Capsicum annuum L.) Hot pepper seeds were primed in aerated solution of putrescine, spermine, or spermidine (25, 50, 75, and 100 mM) for 48 h at 25 ± 2 °C. Significant results (P &lt; 0.05) were observed for different attributes of seed germination and early seedling growth. Polyamines priming resulted in earlier and synchronized germination via improving final...
Tipo: Journal article
Palavras-chave: Seed priming; Capsicum annuum; Polyamines.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300018

Nematicide Effect of Various Organic Soil Amendments on Meloidogyne ethiopica Whitehead, 1968, on Potted Vine Plants
Provedor de dados: 117
Autores: Rivera,Lucia; Aballay,Erwin.
Five organic soil amendments were evaluated for their nematicide effect on root-knot Meloidogyne ethiopica Whitehead, 1968, on potted Vitis vinifera L. var. Chardonnay plants. The amendments included two immature composts: Compost A made with tea (Camellia sinensis (L.) Kuntze) residues, broiler litter and grape pomace; Compost B made with tea residues, rachis and grape pomace; and separately dried tea residues, grape pomace and broiler litter. These amendments were either incorporated or applied as cover to the substrate in 5 L pots at the beginning of spring. A chemical treatment with the nematicide fenamiphos and a control with substrate only were added for comparisons. The assay was composed of 11 treatments with six replicates, with a grape plant as...
Tipo: Journal article
Palavras-chave: Nematode control; Compost; Grape pomace; Tea residues; Chicken manure.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300009

Topoclimatic Modeling of Thermopluviometric Variables for the Bío Bío and La Araucanía Regions, Chile
Provedor de dados: 117
Autores: Díaz M,Diego; Morales S,Luis; Castellaro G,Giorgio; Neira R,Fernando.
Climatic mapping in the Bío Bío and La Araucanía Regions of Chile is primarily in analog form (paper) and delineation of contours, making it unsuitable for digital handling by geographic information systems (GIS). Therefore, in this study, topoclimatic models were created and spatially represented to explain the spatial and temporal variation of monthly mean temperature and precipitation, as a function of variability and singularity of the physiographic characteristics of the Bío Bío and La Araucanía Regions. The physiographic factors considered were latitude, longitude, altitude, aspect and distance to coastline. To elaborate equations, data from thermopluviometric stations of the study area were compiled and systematized. These stations were standardized...
Tipo: Journal article
Palavras-chave: Topoclimatic models; Mean temperature; Mean precipitation; Pluviometric cartographic; GIS; Topoclimáticos; Temperaturas medias; Precipitaciones medias; Cartografía termopluviométrica; SIG.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400011

Relationship between Root Growth of &amp;#39;Thompson Seedless&amp;#39; Grapevines and Soil Temperature
Provedor de dados: 117
Autores: Callejas R,Rodrigo; Canales P,Pablo; García de Cortázar G. de C,Víctor.
With the purpose of characterizing the growth of the root system of table grapes (Vitis vinifera L.) cv. Thompson Seedless and its relationship with soil temperature, research was carried out during the 2004-2005 growing season in vineyards in the Copiapó and Huasco Valleys. Four plants were chosen and rhizotrons were used to measure the growth of the root system. Measurements were performed once a week from September 2004 to September 2005, estimating the intensity of root growth and its annual distribution in the ranges of 0 to 40, 40 to 80 and 80 to 120 cm of soil depth. Temperature sensors were installed in four plants at 25, 50, 75 and 100 cm of soil depth, and the temperature was registered every 1 h. The thermal diffusivity of the soil was...
Tipo: Journal article
Palavras-chave: Roots; Thermal diffusivity; Tablegrape.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400003

Effects of Biofertilizers Combined with Different Soil Amendments on Potted Rice Plants
Provedor de dados: 117
Autores: Javaid,Arshad.
This pot study investigated the effect of the combined application of two commercial biofertilizers viz. Biopower and EM (Effective Microorganisms) on rice (Oryza sativa L.) growth and yield in soils amended with farmyard manure, green manure, and NPK fertilizers. Biopower is a product of the Nuclear Institute for Biotechnology and Genetic Engineering (NIBGE), Pakistan, which contains species of associative and endophytic diazotrophs. EM (effective microorganisms), a product developed by Japanese scientists, consists of co-existing beneficial microorganisms, mainly species of photosynthetic and lactic acid bacteria, as well as yeast. Applying Biopower adversely affected plant growth and yield in NPK fertilizer amendment. Conversely, this biofertilizer...
Tipo: Journal article
Palavras-chave: Associated N2-fixers; Biopower; Effective microorganisms; Rice; Soil amendments.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100019

Heterosis for Yield and Yield Components in Okra (Abelmoschus esculentus (L.) Moench)
Provedor de dados: 117
Autores: Reddy Medagam,Thirupathi; Kadiyala,Haribabu; Mutyala,Ganesh; Hameedunnisa,Begum.
The study of heterosis would help in selection of heterotic crosses for commercial exploitation of F1 hybrids in okra (Abelmoschus esculentus (L.) Moench). Forty five F1S were developed by crossing 10 elite lines of okra: P1(IC282248), P2(IC27826-A), P3(IC29119-B), P4(IC31398-A), P5(IC45732), P6(IC89819), Py(IC89976), P8(IC90107), P9(IC99716), and P10(IC111443), in half diallel fashion during summer 2009. All 45 F1s along with their 10 parents and one standard control (Mahyco Hybrid N° 10) were evaluated in a randomized complete block design with three replicates during early kharif (June to September) 2009 at the Vegetable Research Station, Rajendranagar, Andhra Pradesh, India, for heterosis of yield and its components of okra. Significance of mean...
Tipo: Journal article
Palavras-chave: Abelmoschus esculentus; F1 hybrids; Half diallel crosses; Heterotic pattern; Hybrid vigour; Mean performance; Parental lines.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300003

Comparison of Four Techniques to Estimate Forage Intake by Rams Grazing on a Panicum coloratum L. Pasture
Provedor de dados: 117
Autores: Ferri,Carlos   M; Stritzler,Néstor  P; Brizuela,Miguel  A; Pagella,Horacio   J.
The estimation of daily feed intake is important in the determination of animal production The objective of this experiment was to compare measurements of animal forage intake obtained by the use of four techniques: pre- and post-grazing difference in standing forage mass, total daily feces collection in combination with in vitro diet digestibility, total daily feces collection in combination with diet digestibility estimated by the fecal nitrogen index and the n-alkane technique. The experiment was carried out on a stockpiled Panicum coloratum L. pasture during two growing seasons. The treatments for the first season comprised standing forage mass accumulated after mid-October, mid-January and mid-February mechanical harvest to 8-cm stubble. In the second...
Tipo: Journal article
Palavras-chave: C4 grass; Fecal nitrogen; Forage intake; N-alkanes.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300004

Life, Seasonal Cycles, and Population Fluctuation of Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae), in the Central Plain of La Araucanía Region, Chile
Provedor de dados: 117
Autores: Rebolledo,Ramón; Sheriff,Johnny; Parra,Leonardo; Aguilera,Alfonso.
This study was performed on an alfalfa crop located on the central plain of a Araucanía Region, Chile and in the Laboratorio de Entomología Aplicada de la Facultad de Ciencias Agropecuarias y Forestales at the Universidad de La Frontera. Certain aspects of the biology of Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) were determined, more specifically in relation to its life cycle, seasonality, and population fluctuation. It was established that this coccinellid requires 190.32 ± 10.2 degree-days to complete a generation under laboratory conditions. This information along with the field samplings made it possible to calculate that H. variegata completes four generations per season in the alfalfa crop (Medicago sativa L.).
Tipo: Journal article
Palavras-chave: Life cycle; Seasonal cycle; Population fluctuation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200020

Genetic Characterization of Old Grapevines collected in Oases of the Atacama Desert
Provedor de dados: 117
Autores: Poblete,Ingrid; Pinto,Manuel; de Andrés,María Teresa; Hinrichsen,Patricio.
Old grapevine (Vitis vinifera L.) accessions are a source of genes that could be rescued for use per se or in modern breeding programs. The first step in this rescuing is collecting and characterizing the germplasm from a particular region. This study presents the genetic characterization of 21 grapevine accessions collected from the Atacama Desert in the far North of Chile. Characterization was based on 12 microsatellites (Simple Sequence Repeats, or SSRs) supplemented with Amplified Fragment Length Polymorphic (AFLP) markers. Most of the collected accessions produced red berries and shared the genetic characteristics of the cv. País, an old genotype found throughout America. However, among those red-berried accessions, one showed a severe abortive...
Tipo: Journal article
Palavras-chave: SSR; AFLP; Atacama Desert; Germplasm; ‘Listán Prieto’.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300020

Effect of Scarification, Self-Inhibition, and Sowing Depth on Seed Germination of Lupinus campestris
Provedor de dados: 117
Autores: Gutiérrez Nava,Pedro; De León González,Fernando; Etchevers Barra,Jorge; Casas Fernández,Alejandro.
Lupinus campestris Schltdl. &amp;amp; Cham. grows in shallow fields and disturbed areas of Central Mexico. It has potential to improve soil fertility and as fodder. Seeds of L. campestris show dormancy, and the technology needed to increase its potential use requires information about conditions favouring seed germination. The aim of this study was to evaluate the seed germination responseof L. campestris under controlled (laboratory) and natural field conditions. Under laboratory conditions, 2 yr old seeds had a maximum germination percentage (50%) when they were scarified with sulphuric acid for 90 min prior to sowing and when laboratory light (0.5 µmol m-2 s-1) was maintained during the diurnal period. Without scarification, only about 3% of the seeds...
Tipo: Journal article
Palavras-chave: Seed dormancy; Sowing depth; Green manure.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300003

Irrigation Water Management in Latin America
Provedor de dados: 117
Autores: de Oliveira,Aureo S; Trezza,Ricardo; Holzapfel,Eduardo; Lorite,Ignacio; Paz,Vital Pedro S.
Latin American countries show a great potential for expanding their irrigated areas. Irrigation is important for strengthening local and regional economy and for enhancing food security. The present paper aimed at providing a brief review on key aspects of irrigation management in Latin America. Poor irrigation management can have great impact on crop production and on environment while good management reduces the waste of soil and water and help farmers maximizing their profits. It was found that additional research is needed to allow a better understanding of crop water requirements under Latin American conditions as well as to provide farmers with local derived information for irrigation scheduling. The advantages of deficit irrigation practices and the...
Tipo: Journal article
Palavras-chave: Irrigation; Evapotranspiration; Deficit irrigation; Remote sensing.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500002

Evaluation of On-Farm Quick Tests on Slurries from Southern Chile Dairy Farms
Provedor de dados: 117
Autores: Salazar S,Francisco; Rosas U,Marianela.
Currently in Chile, there is a lack of tools to determine the real-time nutrient contribution of slurries. This study aims to evaluate three quick tests for their accuracy in estimating the total contents of N (TN), P (TP), K (TK), and ammonium-N (N-NH4+) in dairy slurries. The quick tests included the Agros Nova Meter, Quantofix N Volumeter, and a hydrometer. While the Agros and Quantofix meters directly measure the ammonium-N content; the hydrometer indirectly estimates the total content of N, P, and K based on linear relationships with the slurry DM. Samples (73) were collected from dairy farms along Southern Chile (39° to 44° S and 71 to 73° W). Analyses were carried out on laboratory conditions using conventional techniques as well as using each of...
Tipo: Journal article
Palavras-chave: Slurry; Organic residue; Chemical analysis; Nutrients.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300021

CO2 and N2O emissions from an Andisol in Chile under a no-till system using non-fixed closed chambers
Provedor de dados: 117
Autores: Muñoz,Cristina; Paulino,Leandro; Vera,Jenniffer; Zagal,Erick.
Chile has different types of soil and climate conditions that favor a wide range of agricultural activities that can generate potential atmospheric contamination like greenhouse gases (GHG). Nevertheless, the contribution of agricultural soils to atmospheric emissions has yet to be measured in Chile. The aim of this study was to assess seasonal variability of CO2 and N2O effluxes in situ from a volcanic ash-derived soil under different agronomic management practices. Gas samples were obtained from headspaces of non-fixed closed chambers in an annual crop rotation under a no-till system in an Andisol in southern Chile (36° S). Two N-sources (NH4+ and NO3-) and ammonium fertilization plus two lime doses (0.5 and 1 Mg ha-1) were considered for soil treatments...
Tipo: Journal article
Palavras-chave: Greenhouse gases; Agriculture; Nitrogen; Global change; Air pollution.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200013

Simulation of Dry Matter Productivity and Water Dynamics in a Chilean Patagonian Range
Provedor de dados: 117
Autores: Castellaro G,Giorgio; Morales S,Luis; Ahumada,Mario; Barozzi,Azelio.
This paper describes a simulation model combining the main components of water balance and growth of perennial grassland steppe in Chilean Patagonia, to estimate long-term annual production (Yr, kg ha-1) and sheep carrying capacity (GC, sheep equivalent [EO] ha-1). The model is based on climate-water balance relationships, where the basic process is evapotranspiration. The model calculates Yr depending on the accumulation of transpiration and the water use efficiency from the time of growth initiation until the grassland accumulates the maximum amount of dry matter (DM). Depending on Yr, the DM requirement of EO, the proper use factor of grassland and a slope correction factor, a range site GC is calculated. Simulations were performed using actual climate...
Tipo: Journal article
Palavras-chave: Grassland simulation models; Grazing capacity; Patagonian steppe range; Capacidad de carga; Modelos de simulación de praderas; Pastizales esteparios de la Patagonia.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300009

Zinc Fertilization Effects on Seed Cadmium Accumulation in Oilseed and Grain Crops Grown on North Dakota Soils
Provedor de dados: 117
Autores: Rojas-Cifuentes,Gonzalo A; Johnson,Burton L; Berti,Marisol T; Norvell,Wendell A.
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Tipo: Journal article
Palavras-chave: Soil series; Seed; Uptake; Nutrients; Contamination.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100019

Rootstock Effect on the Tolerance of cv. Hass Avocado Plants to Nacl Stress
Provedor de dados: 117
Autores: Castro V,Mónica; Iturrieta E,Rodrigo; Fassio O,Claudia.
The avocado tree (Persea americana Mill.) is one of the species most sensitive to salinity. Since the root system of this species is particularly affected by this type of stress, it is crucial to find a rootstock that is tolerant to saline water irrigation. Plant material from the cv. Hass was grafted on five rootstocks to find possible candidates: the clonal ‘Duke 7’, ‘Nabal’, ‘Degania 117’,’Mexicola’, and ‘Zutano’ seedlings. One year-old plants were placed in 55 L pots; river sand was used as substrate, and the plants were fertilized with a modified Hoagland solution. Vegetative growth and internal nutrient content were compared with control plants with 30 mg L-1 of Cl-, and plants treated with 200 mg L-1 Cl- for 130 days using NaCl in the nutrient...
Tipo: Journal article
Palavras-chave: Chloride; Sodium; NaCl; Salinity stress; Rootstocks.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300003

Insecticidal Effect of Fruit Extracts from Xylopia aethiopica and Dennettia tripetala (Annonaceae) against Sitophilus oryzae (Coleoptera: Curculionidae)
Provedor de dados: 117
Autores: Ukeh,Donald A; Oku,Ene E; Udo,Idorenyin A; Nta,Abo I; Ukeh,Jude A.
The insecticidal and repellent activities of fruit extracts of Xylopia aethiopica (Dunal) A. Rich. and Dennettia tripetala (Baker f.) G.E. Schatz belonging to the family Annonaceae was studied against Sitophilus oryzae (L.), an economic, primary post-harvest pest of rice, and other cereal products. Infested rice grains (100 g) treated with 1, 2, 3, 4, and 5% (w/w) powders of both plants were evaluated for toxicity against S. oryzae every 24 h for 3 d, and during Fi progeny emergence. The essential oils of both plants were also applied at 0.5, 1, 1.5 and 2 mg cm-2 filter paper in Petri dishes for toxicity bioassays at 24 h exposure. Repellence bioassay with 10 &amp;#956;L solution of essential oils on filter paper was performed in a Y-Tube airflow...
Tipo: Journal article
Palavras-chave: Essential oils; Powders; Repellence; Toxicity; Y-Tube olfactometer.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200005

Low Genetic Diversity Among Garlic (Allium sativum L.) Accessions Detected Using Random Amplified Polymorphic DNA (RAPD)
Provedor de dados: 117
Autores: Paredes C,Mario; Becerra V,Viviana; González A,María I.
Garlic (Allium sativum L.) is a species of vegetative propagation, showing high morphological diversity. Besides, its clones have specific adaptations to different agroclimatic regions. The objective of this study was to determine the genetic diversity of 65 garlic clones collected in Chile and introduced from different countries, by using RAPD (Random Amplified Polymorphic DNA). Fourty random primers of 10 mers generated a total of 398 bands with an 87% of polymorphism. Each primer amplified between two and 20 bands. The size of the fragments obtained fluctuated between 3200 and 369 bp. The results showed that the clones analyzed had a genetic similarity rate of 94%. In addition, 70% of them were clustered in one major group. However, in spite of that...
Tipo: Journal article
Palavras-chave: Germplasm; Genetic diversity; RAPD diversity.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100001

Temporal and spatial variability of structure dependent properties of a volcanic ash soil under pasture in southern Chile
Provedor de dados: 117
Autores: Dec,Dorota; Dörner,José; Balocchi,Oscar.
Prairies are a main source for livestock feeding in southern Chile. The aim of this research was to define how grazing events and natural wetting and drying cycles (WD) affect the spatial and temporal variability of the soil’s structural properties. The investigation was conducted in a Duric Hapludand, Valdivia Series. Penetration resistance (PR) and volumetric water content (WC), measured in situ, were used to prepare maps which show i) temporal (1383 to 3047 kPa for 46 to 16% WC) and spatial changes, and ii) grazing events as an important factor influencing spatial changes in PR (differences of 3421 kPa between max and min values). Grazing and WD cycles induced changes in the soil’s mechanical stability and pore functions, which indicate that...
Tipo: Journal article
Palavras-chave: Penetration resistance; Water content; Mechanical strength; Porous system; Andisol.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200015

Comparison of Regression and Neural Networks Models to Estimate Solar Radiation
Provedor de dados: 117
Autores: Bocco,Mónica; Willington,Enrique; Arias,Mónica.
The incident solar radiation on soil is an important variable used in agricultural applications; it is also relevant in hydrology, meteorology and soil physics, among others. To estimate this variable, empirical models have been developed using several parameters and, recently, prognostic and prediction models based on artificial intelligence techniques such as neural networks. The aim of this work was to develop linear models and neural networks, multilayer perceptron, to estimate daily global solar radiation and compare their efficiency in its application to a region of the Province of Salta, Argentina. Relative sunshine duration, maximum and minimum temperature, rainfall, binary rainfall and extraterrestrial solar radiation data for the period...
Tipo: Journal article
Palavras-chave: Modeling; Prediction; Linear regression; Multilayer perceptron.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300010

Expression of Early Light Induced Protein in Grapevine and Pea, under Different Conditions and its Relation with Photoinhibition
Provedor de dados: 117
Autores: Berti,Maritza; Pinto,Manuel.
Early light induced proteins (ELIP) are a type of proteins which are expressed before than other chloroplast proteins in the presence of light. These proteins have been studied in a large number of annual species such as pea (Pisum sativum L.), barley (Hordeum vulgare L.) and Arabidopsis sp. In perennials plants the studies about ELIPs are very scarce. The possible photoprotective function of the ELIPs has motivated the interest in investigating the presence of this type of proteins in a perennial plant such as grapevine (Vitis vinifera L.) and if their characteristics differ from those found in annual plants. In this paper a comparative study was conducted on the ELIPs expression in grapevine and pea to investigate whether there are differences regarding...
Tipo: Journal article
Palavras-chave: Photoinhibition; ELIPs induction; Abiotic stress; Vitis vinifera; Pisum sativum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300011

Influence of Rootstocks on Nitrogen, Phosphorus and Potassium Content in Petioles of Four Table Grape Varieties
Provedor de dados: 117
Autores: Ibacache G,Antonio; Sierra B,Carlos.
Four field trials were conducted at Vicuña Experimental Center (30°02' S, 70°44' W) located in the Coquimbo Region, Chile, over four seasons, 2002-2003 to 2005-2006, to determine the influence of 10 rootstocks (Freedom, Harmony, Saint George, Salt Creek, SO4, 1613C, 1103P, 99R, 110R, 140Ru, as well as own roots vines) on nutrient content in petioles of vars. Flame Seedless, Thompson Seedless, Superior Seedless and Red Globe grapevines (Vitis vinifera L.). The trials took place at a site that had previously planted to vineyard. The experimental design was randomized complete block with four replicates. Petioles opposite to clusters were taken at bloom as samples and analyzed for total N, P and K content. Significant differences in nutrient levels due to...
Tipo: Journal article
Palavras-chave: Grapevine; Mineral nutrition; Rootstocks; Petiole analysis; Chile.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400004

Analysis of Hydraulic Conductance Components in Field Grown, Mature Sweet Cherry Trees
Provedor de dados: 117
Autores: Oyarzún,Ricardo; Stöckle,Claudio; Whiting,Matthew.
As a necessary step towards understanding soil water extraction and plant water relationships, the components of hydraulic conductance (K) of mature sweet cherry (Prunus avium L.) trees were evaluated in situ based on a Ohm´s law analog method. In June 2004, K was determined for 10-yr-old ‘Bing’/‘Gisela® 5’ trees, from simultaneous measurements of whole canopy gas exchange and leaf (sunlit and shaded) and stem water potentials (&amp;#936;). Leaf water potential of sunlit leaves was lower than shaded leaves, reaching minimum values of ca. -2.3 MPa around 14:00 h (solar time). Average total hydraulic conductance was 60 ± 6 mmol s-1 MPa-1, presenting a slight decreasing trend as the season progressed. The analysis of tree K components showed that it was...
Tipo: Journal article
Palavras-chave: Plant water relations; Transpiration; Water potential; Whole-canopy gas exchange.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100006

Comparative Efficacy of Different Weed Management Strategies in Wheat
Provedor de dados: 117
Autores: Ehsan Safdar,Muhammad; Asif,Muhammad; Ali,Amjed; Aziz,Ahsan; Yasin,Muhammad; Aziz,Mudassir; Afzal,Muhammad; Ali,Asghar.
Weed management programs should focus on environmental safety along with benefits to the farmer. We evaluated the effects of various weed control methods: ‘daab’ practice (stale seed bed technique), manual hoeing, and the chemical method (mixture of Buctril Super 60EC [bromoxynil + MCPA]0.45 kg ai ha-1 and Puma Super 75EW [fenoxaprop-P-ethyl] 0.75 kg ai ha-1) in combination with different planting geometries: 22.5 cm apart single row, 22.5 cm apart crisscross double row, 30 cm apart single row and broadcast sowings on weed control and grain yield of spring wheat (Triticum aestivum L.) var. Sehar 2006 at the University College of Agriculture, University of Sargodha, Pakistan, during the winters of 2009 and 2010. The chemical method, manual hoeing and ‘daab’...
Tipo: Journal article
Palavras-chave: Weed control; Sowing pattern; ‘daab’ practice; Crisscross sowing; Yield components.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200003

Pathogenic and Genetic Diversity among Iranian Isolates of Macrophomina phaseolina
Provedor de dados: 117
Autores: Rayatpanah,Siavosh; Nanagulyan,Siranoush G; Alav,Seyed V; Razavi,Mohammad; Ghanbari-Malidarreh,Abbas.
Charcoal rot, caused by Macrophomina phaseolina (Tassi) Goid., is an economically important disease of oilseed plants in Northern Iran. Seventy isolates of M. phaseolina were obtained from different hosts, including soybean (Glycine max L.), and sunflower (Helianthus annuus L.) in the northern oilseed planting regions of Iran. RAPD-PCR amplification profiles, by using of six random OPA primers (kit A) showed polymorphisms among the isolates. The primer OPA-13 (5'_ CAGCACCCAC_3') amplified the genomic DNA of all isolates of M.phaseolina producing 4-12 bands of sizes between 0.25 and 2.3 kb. Unweighted pair-group method with arithmetic mean (UPGMA) analysis classified the isolates into the nine major groups with 64% similarity. Pathogenicity of isolates was...
Tipo: Journal article
Palavras-chave: Charcoal rot; Oilseed plants; Disease index.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100007

Encapsulated Somatic Embryos and Zygotic Embryos for Obtaining Artificial Seeds of Rauli-Beech (Nothofagus alpina (Poepp. &amp;amp; Endl.) Oerst.)
Provedor de dados: 117
Autores: Cartes R,Priscila; Castellanos B,Hermes; Ríos L,Darcy; Sáez C,Katia; Spierccolli H,Scarlette; Sánchez O,Manuel.
Somatic and zygotic embryos from mature seeds of rauli-beech, Nothofagus alpina (Poepp. &amp;amp; Endl.) Oerst., were encapsulated in different artificial endosperms in order to generate a cover that fulfills the function of nourishment and protection of the embryos, facilitating their later germination. The content of sodium alginate varied by 4%, 3%, and 2%, as did the immersion time in calcium chloride (CaCl2), which acts as complexing agent. The artificial endosperm components of the Murashige and Skoog medium (MS) were added, supplemented with 0.5 mg L-1 indolacetic acid (IAA), 0.5 mg L-1 naphthaleneacetic acid (NAA), 2 mg L-1 6-benzylaminopurine (BAP) and 30 g L-1 sucrose. The germinative behaviors of encapsulated somatic and zygotic embryos were...
Tipo: Journal article
Palavras-chave: Rauli-beech; Somatic embryogenesis; Synthetic seed; Sodium alginate.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100014

Improving Harvesting Techniques to Ensure Sphagnum Regeneration in Chilean Peatlands
Provedor de dados: 117
Autores: Diaz,Maria F; Silva,Wladimir.
Sphagnum species, primarily Sphagnum magellanicum Brid., are used internationally as a substrate for horticulture. Market demands have promoted indiscriminate exploitation leading to a number of potentially negative ecological and social consequences, including disruption of Sphagnum ecosystems, changes in water storage capacity of moss wetlands affecting water supply to rural communities and reduction of biodiversity. This study proposes improvements in harvesting techniques to ensure moss regeneration and promote sustainability of moss cover in harvested areas. The aim of this study was to determine the maximum harvesting depth for moss regeneration. Samples were taken and divided into sections associated with different depths. We recorded and marked the...
Tipo: Journal article
Palavras-chave: Sphagnum moss; Sustainable management; Wetlands.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200021

Continuous Stabilization of Chardonnay with Ion-Exchage Resin: Influence on Protein and Phenolic Profile of Wine
Provedor de dados: 117
Autores: de Bruijn,Johannes; Valdebenito,Ana; Loyola,Cristina; Serra,Ignacio; Salazar,Fernando; López,Francisco.
Unstable proteins may react with polyphenols, forming haze and precipitation in white wines. Therefore, the adsorption of these wine proteins is an essential step in the production of white wines. The objective of this study was to determine the influence of adsorption of these proteins on the stability, and protein and phenolic composition of a Chardonnay wine. In this work, protein stabilization of Chardonnay wine was done by continuous adsorption using a packed bed with a SP-Trisacryl-M adsorbent (Sigma-Aldrich). A more pronounced breakthrough of proteins and turbidity causing compounds was found after treating 65 bed volumes of wine by the resin. An increased retention of the protein fraction of 20-50 kDa during the first 62 bed volumes of treated wine...
Tipo: Journal article
Palavras-chave: Adsorption; Trisacryl; Fining; Chile.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100007

Effect of Feeding Distillery Dried Grains to Lactating Cows on Farms in the Southern Dairy Region of Chile
Provedor de dados: 117
Autores: Shaver,Randy; Ehrenfeld,Ricardo; Olivares,Mario; Cuellar,Jaime; Inostroza,Francisco.
A field trial was conducted on five farms to determine the effect of feeding distillery dried grains (DDGS) on milk production in the southern dairy region of Chile. The trial was repeated on each farm during winter (July and August; primarily silage-based rations) and spring (November and December; pasture-based rations). Only for one farm could the treatments be applied concurrently by feeding different iso-nitrogenous concentrate mixes to randomly assigned cows in the milking parlor with data analyzed as a randomized complete block design. Milk yield tended (P &lt; 0.07) to be greater for cows fed DDGS (2.0 kg cow-1 d-1) by 1.9 kg d-1 in winter and 1.8 kg d-1 in spring. In winter, milk protein yield was (P &lt; 0.02) greater for cows fed DDGS by 73 g...
Tipo: Journal article
Palavras-chave: Dairy cows; Distillery dried grains; Milk production; Pasture.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200018

Identification of Two Species of Fusarium Link that Cause Wilting of Colored Callas (Zantedeschia aethiopica (L.) Spreng.) Cultivated under Greenhouse Conditions in Chile
Provedor de dados: 117
Autores: Ciampi P,Luigi; Nissen M,Juan; Venegas G,Elizabeth; Fuentes P,Ricardo; Costa L,Marcia; Schöbitz T,Renate; Alvarez D,Eduardo; Alvarado A,Pilar.
Calla (Zantedeschia aethiopica (L.) Spreng.) is a flower that is conquering international markets. It is very important to maintain the healthiness of the crop during its development in order to obtain high quality plants that meet the demands of the markets. The objective of this investigation was to determine the etiological agent(s) of a pathology never observed before in Chile that causes vascular wilt during the cultivation of colored calla developed under greenhouse conditions. Fungal isolates were collected from infected plants. Pathogenicity tests, microscopic observations, and scanning electronic microscopy evaluations were also conducted. Healthy calla tubers were inoculated with isolates of the genus Fusarium Link. Plants grown during 5 months...
Tipo: Journal article
Palavras-chave: Colored calla.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000400006

Pistillate Flower Abcission Symptoms of ‘Serr’ Walnut (Juglans RegiaL.)
Provedor de dados: 117
Autores: González R,Cristián; Lemus S,Gamalier; Reginato,Gabino.
Pistillate flower abscission (PFA) severely affects walnut (Juglans regia L.) production, mainly of the cultivar ‘Serr’. A study on symptoms of flower abortion in walnut ‘Serr’, induced by excess or lack of pollen, was carried out following the evolution of flowers and peduncles. Hand pollinated flowers, with different pollen concentrations: 0, 1, 5, 25, 50 and 100% pollen diluted (w/w) in talcum powder, showed external and internal abortion symptoms. External symptoms were recorded directly from the tree, while for internal symptoms, flower excisions stained with blue Toluidin-O at 0.05%, were analyzed under an optical microscope. Excess pollen abortion produced flowers with rapid damage. The growth rate was very low, involucre brightness was lost and the...
Tipo: Journal article
Palavras-chave: Lack of pollen; Excess of pollen; Pollination.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200008

Insecticied effect of silver and zinc nanoparticles against Aphis nerii Boyer of fonscolombe (Hemiptera: Aphididae)
Provedor de dados: 117
Autores: Rouhani,Mohammad; Amin Samih,Mohammad; Kalantari,Salma.
The oleander aphid, Aphis nerii Boyer de Fonscolombe, is one of the common pests of ornamental plants in the families of Apocynaceae and Sclepiadaceae and distributed throughout the world, which has been responsible for the mortality of a large number of oleander (Nerium oleander L.) shrubs each year. In this research, the insecticidal activity of Ag nanoparticles against the A. nerii was investigated. Nanoparticles of Ag and Ag-Zn were synthesized through a solvothermal method, and using them, insecticidal solutions of different concentrations were prepared and tested on A. nerii. For comparison purposes, imidacloprid was also used as a conventional insecticide. In the experiments, the LC50 value for imidacloprid, Ag and Ag-Zn nanoparticles were...
Tipo: Journal article
Palavras-chave: Imidacloprid; Oleander aphid; Nerium oleander; Solvothermal method.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400020

Field Insect Pests and Crop Damage Assessment of Pigeon Pea (Cajanus cajan [L.] Huth) grown under Ratoon and in Mixture with Maize
Provedor de dados: 117
Autores: Dasbak,Madang A; Echezona,Bonaventure C; Asiegbu,Jerry E.
The widespread adoption of cropping systems that are sustainable and environmentally friendly is vital for the macroeconomic survival of civilization. Intercropping could ensure stability of insect populations in a system. A 3-yr (2005-2007) field trial was therefore carried out in Nigeria under regular and ratoon crops to evaluate five recently developed pigeon pea (Cajanus cajan [L.] Huth) genotypes (ICPL 87, ICPL 161, ICPL 85063, ICP 7120, and ICPL 87119) from the International Crops Research Institute for Semi-Arid Tropics (ICRISAT) and one local variety for their relative performance and susceptibility to insect pests. The pigeon pea genotypes were in a mixture with two maize genotypes (Zea mays L., open-pollinated and hybrid) in regular crops for 2...
Tipo: Journal article
Palavras-chave: Cropping system; Ratoon crops; Regular crop.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100008

Selection of a Representative Core Collection from the Chilean Common Bean Germplasm
Provedor de dados: 117
Autores: Paredes C,Mario; Becerra V,Viviana; Tay U,Juan; Blair,Matthew  W; Bascur B,Gabriel.
Race Chile is an important component of the genetic structure of the common bean (Phaseolus vulgaris L.). The germplasm bank of the Instituto de Investigaciones Agropecuarias INIA contains 1200 accessions distributed mainly into two Active Working Germplasm Banks at INIA La Platina (Santiago) and at INIA Quilamapu (Chillán) and also the Germplasm Base Bank at INIA Intihuasi (La Serena). The Chilean collection possesses accessions collected throughout the country. One way to study and use the germplasm stored at the Seed Banks is the formation of a core collection. The objectives of this work were: a) To establish a common bean core collection with the germplasm collected throughout the country, and b) to evaluate its representatives based on phenotypic...
Tipo: Journal article
Palavras-chave: Phenotypic variability; Bean gene pools; Race Chile.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100001

Influence of Municipal Solid Waste Compost on Soil Properties and Plant Reestablishment in Peri-Urban Environments
Provedor de dados: 117
Autores: Civeira,Gabriela.
Soils in urban areas often present characteristics that might submit these environments to erosion processes. Applying municipal solid wastes (MSW) composts to soils have been suggested as a means to improve physical and chemical properties. A field experiment with a completely randomized design was conducted in a Typic Argiudoll from a degraded area in Buenos Aires City. The objective was to evaluate the effect of MSW compost application on soil properties, residue decomposition and Poa (Poa pratensis L.) reestablishment. At the beginning of the trial, compost was prepared and applied in a bare soil on 0.25 m² square plots afterwards litterbags were incorporated and Poa was sown. Compost amounts were: 0 (control); 2 (low); 4 (medium) and 7 kg m-2 (high)...
Tipo: Journal article
Palavras-chave: Soil restoration; Municipal solid waste compost; Soil properties.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300012

Combining Multivariate Analysis and Pollen Count to Classify Honey Samples Accordingly to Different Botanical Origins
Provedor de dados: 117
Autores: Corbella,Eduardo; Cozzolino,Daniel.
This study reports the combination of multivariate techniques and pollen count analysis to classify honey samples accordingly to botanical sources, in samples from Uruguay. Honey samples from different botanical origins, namely Eucalyptus spp. (n = 10), Lotus spp. (n = 12), Salix spp. (n = 5), “mil flores” (Myrtaceae spp.) (n = 12) and coronilla (Scutia buxifolia Reissek) (n = 10) were analysed using Melissopalynology (pollen identification). Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify the honey samples accordingly to their botanical origin based on a pollen count. Honey samples of higher percentage (&gt; 70%) of Eucalyptus, Lotus and Scutia pollen were 100% correctly classified, whilst samples from...
Tipo: Journal article
Palavras-chave: Honey; Uruguay; Principal component analysis; Linear discriminant analysis; Pollen analysis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100010

Allelopathic Effects of Sunflower Residue on Growth of Rice and Subsequent Wheat Crop
Provedor de dados: 117
Autores: Bashir,Uzma; Javaid,Arshad; Bajwa,Rukhsana.
Sunflower (Helianthus annuus L.) is a well known allelopathic plant species. However, Pakistani farmers generally incorporate the sunflower residue in the soil with the aim to enhance soil fertility and organic matter. Field experiments were, therefore, carried out to evaluate the effect of sunflower residue incorporation on growth and yield of rice (Oryza sativa L.) and subsequent wheat (Triticum aestivum L.) crop. For rice crop, there were four treatments viz. control, sunflower residue incorporation (RI), NPK fertilizers, and NPK+RI. Two rice varieties (Basmati Pak and Basmati Super) were cultivated. Incorporation of sunflower residue markedly reduced plant growth and yield in 'Basmati Pak'. There was 34% reduction in yield of this variety due to RI....
Tipo: Journal article
Palavras-chave: Allelopathy; Genotypic tolerance; Oryza sativa; Helianthus annuus; Triticum aestivum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300004

Water Erosion Prediction Using the Revised Universal Soil Loss Equation (RUSLE) in a GIS Framework, Central Chile
Provedor de dados: 117
Autores: Bonilla,Carlos A; Reyes,José L; Magri,Antoni.
Soil erosion is a growing problem in Central Chile, particularly in coastal dry lands, where it can significantly decrease the productivity of rainfed agriculture and forestry. In this study, the Revised Universal Soil Loss Equation (RUSLE) was integrated into a Geographic Information System (GIS), and used to evaluate the effects of different combinations of vegetative cover on soil erosion rates for Santo Domingo County in Central Chile. Implementing RUSLE in the GIS required a complete description of the county’s soils, climate, topography and current land use/land cover. This information was compiled in rasters of 25 x 25 m cells. RUSLE parameter values were assigned to each cell and annual soil loss estimates were generated on a cell by cell basis....
Tipo: Journal article
Palavras-chave: RUSLE; Water erosion; Soil conservation; Forestry; Changes in land use/land cover; Central Chile.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100017

Evaluation of Resistance of Cucumber Cultivars to the Vegetable Leafminer (Liriomyza sativae Blanchard) (Diptera: Agromyzidae) in Greenhouse
Provedor de dados: 117
Autores: Basij,Moslem; Askarianzaeh,Alireza; Asgari,Shahriyar; Moharramipou,Saeid; Rafezi,Ramin.
The leafminer, Liriomyza sativae Blanchard, is distributed around the world and is an important pest of vegetables and ornamentals. Given the resistance potential of the leafminer to current insecticides, the use of resistant plant cultivars and parasitoids could be effective integrated pest management (IPM) strategies against it. Cucumber (Cucumis sativus L.) is a preferred host for this insect. Seventeen cultivars of cucumber have been evaluated to study resistance mechanisms to L. sativae. All cucumber cultivars were evaluated in screening tests in greenhouse with indices such as the number of leafminer stings, the number of larval mines, the proportion of larval mines to leafminer stings, and the rate of injury. Significant differences (p &lt; 0.01)...
Tipo: Journal article
Palavras-chave: Cucumber cultivar; Screening; Antibiosis; Screening.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300008

The Karyotype of Alstroemeria diluta Ehr. Bayer subsp. chrysantha (Alstroemeriaceae)
Provedor de dados: 117
Autores: Baeza,Carlos M; Ruiz,Eduardo; Novoa,Patricio.
The karyotype of Alstroemeria diluta subsp. chrysantha Ehr. Bayer from Chile was examined. The species has 2n = 2x = 16 chromosomes, with 4m + 4sm + 2st-sat + 4t + 2t-sat. The reported karyotype is very asymmetrical (AsK % = 71.4 and Syi = 40.0%). This karyotype is similar to that published previously for Alstroemeria graminea Phil.
Tipo: Journal article
Palavras-chave: Karyotype; Ornamental plant; Chile.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400018

Adaptability and Genotype x Environment Interaction of Spring Wheat Cultivars in Chile using Regression Analysis, AMMI, and SRAG
Provedor de dados: 117
Autores: Castillo,Dalma; Matus,Iván; del Pozo,Alejandro; Madariaga,Ricardo; Mellado,Mario.
Wheat (Triticum aestivum L.) genetic improvement objectives include obtaining cultivars capable of expressing their maximum potential yield and quality in diverse environments. This make necessary to know and define the environment in which a variety can express its maximum potential yield and quality. The objective of this study was to assess which method is the most efficient to study cultivars response in multiple environments. For this, we analyze the adaptability, stability, and genotype x environment (GxE) interaction effect, grain yield, sedimentation, and wet gluten content of 13 spring wheat cultivars sown in six environments in the central-south and southern zones of Chile during two seasons. The data were analyzed by regression analysis,...
Tipo: Journal article
Palavras-chave: AMMI; SREG; GxE; Bread wheat.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200001

Ethylene, Enzymatic and Respiratory Pattern Evolution in Loquat (Eriobotrya japonica (Thunb.) Lindl.) cv. Golden Nugget in the Last four Sequential Stages of Maturation
Provedor de dados: 117
Autores: Undurraga M,Pedro L; Olaeta C,José A; Cancino,Cristian.
There is some controversy regarding the respiratory pattern of loquat (Eriobotrya japonica [Thunb.] Lindl.). Thus in order to provide information on this aspect of loquat, fruit of 50-70 g, from cv. Golden Nugget were harvested in four stages of maturity: green (BBCH 709), color break (BBCH 801), yellow (BBCH 807), and orange (BBCH 809). The parameters evaluated in each stage were: soluble solids, titratable acidity, respiration, ethylene generation, and activity of the enzymes pectin methyl esterase (PME), peroxidase, polyphenoloxidase (PPO), polygalacturonase (PG), and cellulose, and the soluble solids:acidity ratio was calculated. The results show that ethylene concentration increased at the time of color break, which was not the case for the change in...
Tipo: Journal article
Palavras-chave: Color skin; Peroxidase; CO2; Fruit quality; Polygalacturonase.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400005

Effect of Irrigation Levels on Dissolved Organic Carbon Soil Distribution and the Depth Mobility of Chlorpyrifos
Provedor de dados: 117
Autores: Junod,Julio; Zagal,Erick; Sandoval,Marco; Barra,Ricardo; Vidal,Gladys; Villarroel,Mario.
Water flows provided by irrigation systems may be associated with dissolved organic carbon (DOC) content in the soil solution and may modify the mobility of pesticides, such as chlorpyrifos (CHP). These compounds were analyzed under field conditions, evaluating their distribution in the soil profile under excessive irrigation in a Humic Haploxerand soil. The trial was carried out in soil columns located under the canopy of apple trees (Malus domestica Borkh.) in an orchard located in the Bío-Bío Region, Chile. The insecticide CHP was applied 120 g hL-1, and later the natural run off was collected from the foliage to the columns. Surface irrigation was used as a control, the equivalent to 4 L h-1 weekly, plus two treatments over the columns of 6 and 8 L h-1...
Tipo: Journal article
Palavras-chave: Pesticides; Organic matter; Volcanic soil.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300017

Integral Study of Atrazine Behaviour in Field Lysimeters in Argentinean Humid Pampas Soils
Provedor de dados: 117
Autores: Hang,Susana; Andriulo,Adrián; Sasal,Carolina; Nassetta,Mirtha M; Portela,Silvina; Cañas,Ana I.
Atrazine behavior during crop maize (Zea mays L.) production in soils of Argentine humid pampas was investigated. Lysimeters (3.3 x 3.3 x 1.4 m) with a Typic Argiudoll (Pergamino) and others with a Typic Hapludoll (Junín) were monitored for drainage water content and atrazine concentrations in soil and water. Soil profiles were sampled in four depths in three dates, and water drainage pooled in four periods. Most of atrazine loss in drainage occurred within 30 d of atrazine application being 0.13% and 0.03% of the total atrazine applied for Pergamino and Junín, respectively. Under laboratory conditions half-life average in both profiles was 16 d. Atrazine extractable residues (AER) in lysimeters showed differences in quantity and distribution between both...
Tipo: Journal article
Palavras-chave: Atrazine extractable residues; Preferential flow; Half-life; Contamination risk.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100011

Controlled Rhizogenesis and Mycorrhization of Hazelnut (Corylus avellana L.) Cuttings with Black Truffle (Tuber melanosporum Vitt.)
Provedor de dados: 117
Autores: Santelices,Rómulo; Palfner,Götz.
Hazelnut (Corylus avellana L.) is commonly used as mycorrhizal host for Tuber melanosporum Vitt. (black truffle). Black truffle orchards have been established in and outside its natural distribution area, currently also in Chile. Hazelnut can be propagated rapidly by cuttings, which, however, may not easily form mycorrhizal symbiosis under laboratory conditions. We successfully inoculated hazelnut cuttings with T. melanosporum and studied the effects of culture conditions, plant material and inoculum age on rhizogenesis and mycorrhization. Cuttings from sucker shoots showed the highest rooting rate (88.5%). Perlite and vermiculite as substrate increased root length (9.6 cm ). Treatment with auxin significantly increased root yield (up to 27 roots per...
Tipo: Journal article
Palavras-chave: Cuttings; Rhizogenesis; Mycorrhizae; Culture conditions.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200003

Parasitoidism Rate and Life Table Parameters of Aphytis diaspidis (Howard) (Hymenoptera: Aphelinidae) and Hemiberlesia lataniae (Signoret) (Hemiptera: Diaspididae)
Provedor de dados: 117
Autores: Navea O,Dennis; Vargas M,Robinson.
Latania scale, Hemiberlesia lataniae (Signoret), has become a major pest of avocado (Persea americana Mill.) in Chile and has reached high populations in the fruit because of limited natural control. The objective of this study was to identify the biological parameters of the parasitoid Aphytis diaspidis (Howard) as a control agent of latania scale. Postembryonic development, parasitoidism rate, and life table parameters of the parasitoid and scale were determined under laboratory conditions. Aphytis diaspidis postembryonic development and parasitoidism rate varied significantly when evaluated on distinct latania scale stages with the highest survival (56%) occurring at the third scale stage, it also had the shortest development time between egg and adult...
Tipo: Journal article
Palavras-chave: Postembryonic development; Life tables; Parasitoidism; Biological control; White scale; Avocado.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300006

Nitrogen Mineralization and Released Nutrients in a Volcanic Soil Amended with Poultry Litter
Provedor de dados: 117
Autores: Hirzel,Juan; Undurraga,Pablo; Walter,Ingrid.
Optimum application rates of poultry litter (PL) spread out on the farmer´s field is a valuable source of available plant nutrients. The aim of this study was to compare the effect of two rates of PL and conventional fertilization (CF) on N mineralization and P, K, Zn, and Cu availability in an Andisol from Southern Chile under controlled conditions. Aerobic incubation was carried out for a 16-wk period. N mineralization rates were higher (61.5%) with the two PL treatments than with conventional fertilizer (23%). CF was associated with high N availability prior to the start of incubation and slight immobilization during the first week, perhaps due to a more rapid conversion of urea into NH4 which was then temporarily immobilized by the microbial biomass....
Tipo: Journal article
Palavras-chave: Aerobic incubation; Poultry litter; Nitrogen mineralization; Nutrient availability; Volcanic soil.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100012

Influence of double cropping on growth and yield of dry beans with colored plastic mulches
Provedor de dados: 117
Autores: Ibarra-Jiménez,Luis; Valdez-Aguilar,Luis Alonso; Cárdenas-Flores,Antonio; Lira-Saldivar,Hugo; Lozano-del Río,Javier; Lozano Cavazos,Carlos.
There are numerous studies of the use of plastic mulches in vegetable production, but there is little documentation of their use with dry beans (Phaseolus vulgaris L.) in single and double cropping. The objective of this study was to grow dry beans over two consecutive growing seasons using the same plastic mulch of different colors and examine the influence of soil temperature on growth and yield. The experiment was conducted in Saltillo, Coahuila, Mexico, in the spring and summer of 2008. The treatments included four colored plastic mulches: white-on-black, black, silver-on-black, aluminum-on-black, and bare soil as a control. The experimental design was a randomized complete block with four replicates. The percentage of photosynthetically active...
Tipo: Journal article
Palavras-chave: Phaseolus vulgaris; Soil temperature; Photosynthesis; PAR; Plasticulture.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400002

Effect of soil depth and increasing fertilization rate on yield and its components of two durum wheat varieties
Provedor de dados: 117
Autores: Hirzel,Juan; Matus,Iván.
Agronomic practices, climatic variables, and soil conditions are key factors in crop productivity. Although the effects of soil chemical properties and water and agronomic crop management are known, there is little information about effective soil depth and its influence on crop productivity. Since most crop fertilization systems are based on the productive potential associated with climatic conditions and chemical properties of the first 20 cm of soil depth, the objective of this study was to determine the importance of effective depth in terms of increasing fertilization rates on durum wheat (Triticum turgidum L. var. durum) productivity. Two experiments were conducted in the 2006-2007 season in the Santa Rosa Experimental Station (71°54' S, 36°31' W,...
Tipo: Journal article
Palavras-chave: Durum wheat; Soil depth; Fertilization; Triticum turgidum.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100008

Fungistatic Activity Of Essential Oils Extracted from Peumus boldus Mol., Laureliopsis philippiana (Looser) Schodde and Laurelia sempervirens (Ruiz &amp;amp; Pav.) Tul. (Chilean Monimiaceae)
Provedor de dados: 117
Autores: Bittner,Magalis; Aguilera,Milenko A; Hernández,Víctor; Arbert,Cecilia; Becerra,José; Casanueva,María E.
Components of essential oils from the Chilean Monimiaceae, boldo (Peumus boldus Mol.), tepa (Laureliopsis philippiana (Looser) Schodde), and laurel (Laurelia sempervirens (Ruiz &amp;amp; Pav.) Tul.) were determined using Gas Chromatography- Mass Spectrometry (GCMS) and fungistatic activity of the essential oils was tested against Rhizoctonia solani Kühn (Donk), Pythium irregulare Buisman, Ceratocystis pilifera (Fr.) C. Moreau, Phragmidium violaceum (Schultz) G. Winter, and Fusarium oxysporum Schltdl. The essential oils of the Monimiaceae species shared some common components; all three had the 3-carene, &amp;#945;-phellandrene, and &amp;#945;-pinene terpenes. L. philippiana and L. sempervirens also had safrole.The main components were ascaridol in P....
Tipo: Journal article
Palavras-chave: Chilean native trees; Chemical components; Natural fungistatic activity; In vitro analysis.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100004

Utility to Consumers and Consumer Acceptance of Information on Beef Labels in Southern Chile
Provedor de dados: 117
Autores: Schnettler M,Berta; Silva F,Roberto; Sepúlveda B,Néstor.
Credence attributes (production system, animal welfare, traceability, among others) have acquired importance for meat products in developed countries, representing information that must be included on label. A personal survey was administered to 770 consumers in the Bío-Bío and La Araucanía Regions, Chile, to determine the utility of information contained on the label and acceptance of information referred to as credence attributes, as well as to distinguish different consumer segments. The packaging and expiry dates were the most useful aspects of the current information. The greatest degree of agreement with respect to information that should be included was a quality seal, type of animal, handling regarding animal welfare, production system and feeding....
Tipo: Journal article
Palavras-chave: Beef; Label; Animal welfare; Production systems; Traceability.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300010

Borage (Borago officinalis L.) Response to N, P, K, and S Fertilization in South Central Chile
Provedor de dados: 117
Autores: Berti,Marisol T.; Fischer,Susana U.; Wilckens,Rosemarie L.; Hevia,María F.; Johnson,Burton L.
Borage (Borago officinalis L.) is an oilseed with a high gamma-linolenic acid (GLA) content in its seed. The objective of this study was to determine the response of borage seed yield, oil content, and fatty acid composition to N, P, K, and S fertilizer treatments. Three experiments were conducted in Osorno (40º22’ S, 73º04’ W; 72 m.a.s.l.), Chile. The first experiment was conducted during the 2005-2006 growing season, with four N rates (0, 100, 200, and 300 kg N ha-1), three P rates (0, 60, and 120 kg P2O5 ha-1) and two K rates (0 and 150 kg K2O ha-1). The second experiment was conducted in 2006-2007 and evaluated only the effect of four N rates (0, 50, 100 and 150 kg N ha-1) was evaluated because there was no response to P and K in the first experiment....
Tipo: Journal article
Palavras-chave: Seed yield; Gamma-linolenic acid.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200006

Effect of Nitrogen Inhibitors on Nitrous Oxide Emissions and Pasture Growth After an Autumn Application in Volcanic Soil
Provedor de dados: 117
Autores: Vistoso,Erika; Alfaro,Marta; Saggar,Surinder; Salazar,Francisco.
A range of technologies is available to reduce greenhouse gas emissions from agricultural systems. Among these, applying N transformation inhibitors is promising in reducing nitrous oxide (N2O) emissions in both arable and pastoral soils. A randomized complete block design with six replicates was used to quantify the effect of urease (UI) and nitrification (NI) inhibitors on N2O emissions and pasture production from permanent pasture in an Andisol after autumn-applied urea. The N2O emissions were measured periodically for 8 wk with PVC stationary chambers. Mineral N, DM yield, N concentration, and N uptake were analyzed. Our results show that adding fertilizer (40 kg N ha-1) significantly increased N2O emissions by 281% over the control treatment (P &lt;...
Tipo: Journal article
Palavras-chave: Andisol; Emission factor; Urease inhibitor; Nitrification inhibitor; Urea.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100021

Influence of the Genotype on the Anthocyanin Composition, Antioxidant Capacity and color of Chilean Pomegranate (Punica granatum L.) Juices
Provedor de dados: 117
Autores: Sepúlveda,Elena; Sáenz,Carmen; Peña,Álvaro; Robert,Paz; Bartolomé,Begoña; Gómez-Cordovés,Carmen.
The bioactive compounds content in pomegranate (Punica granatum L.) juice is variable and depends on agronomic factors, genetic and fruit maturity. In Chile, the areas with this crop have increased more than 65% in the last 5 years. This paper aims to determine the phenolic composition, antioxidant capacity and chromatic parameters of juices from eight Chilean pomegranate genotypes (PG2 to PG9), containing red (PG2 to PG6) or pink arils (PG7 to PG9). Color, total polyphenol content (using Folin-Ciocalteu reagent), total anthocyanins (by differences in absorbance at different pHs of the juice) and antioxidant capacity (oxygen-radical absorbance capacity, ORAC) were determined. Anthocyanins were identified and quantify using HPLC-DAD and HPLC/ESI-MS, the...
Tipo: Journal article
Palavras-chave: Polyphenols; Bioactive compounds.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100005

Variability of Soil Types in Wetland Meadows in the South of the Chilean Patagonia
Provedor de dados: 117
Autores: Filipová,Ladislava; Hédl,Radim; Covacevich C.,Nilo.
The wetland meadows and pastures (vegas) of the agricultural zone of the Magallanes Region and the Chilean Patagonia are productive and intensively exploited ecosystems. However, there is scarce data about the typology and the physical and chemical properties of the soils that determine the agricultural potential of vegas sites. Sampling of the main horizons of 47 soil profiles was conducted throughout the area. The profiles were described in the field and consequently classified according to the soil typology system of the WRB (IUSS Working Group WRB, 2006). Analyses of bulk and particle densities, capillary water capacity, pH (H2O), pH (CaCl2), texture, organic material, C:N ratio, electrical conductivity, effective cation exchange capacity, N, P,...
Tipo: Journal article
Palavras-chave: Histosols; Fluvisols; Peat; Soil properties; Salinization; Soil degradation.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200010

Integrated Water Resources Management for Sustainable Irrigation at the Basin Scale
Provedor de dados: 117
Autores: Billib,Max; Bardowicks,Karin; Arumí,José Luis.
The objective of this paper is to review the state of art on integrated water resources management (IWRM) approaches for sustainable irrigation at the basin scale under semi-arid and arid climatic conditions, with main emphasis on Latin America, but including case studies of other semi-arid and arid regions in the world. In Latin America the general concept of IWRM has proved to be hard to implement. Case studies recommend to develop the approach from lower to upper scale and oriented at the end-user. As IWRM is an interdisciplinary approach and used for very different objectives, the main emphasis is given to IWRM approaches for sustainable irrigation and their environmental aspects. The review shows that in Latin America the environmental impact is...
Tipo: Journal article
Palavras-chave: Water resources management; Basin; Sustainability; Irrigation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500007

Population Growth of Rhopalosiphum padi L. (Homoptera: Aphididae) on Different Cereal Crops from the Semiarid Pampas of Argentina under Laboratory Conditions
Provedor de dados: 117
Autores: Descamps,Lilian R; Sánchez Chopa,Carolina.
The bird cherry-oat aphid Rhopalosiphum padi L. (Homoptera: Aphididae) is one of the main pests in a number of crops in the semiarid Pampas of Argentina. In the present study, the effect of different host plants, including Triticum aestivum L., ×Triticosecale Wittm., Hordeum vulgare L., Hordeum distichum L., Avena sativa L., and Secale cereale L. on biological parameters of R. padi L. was studied in the laboratory at 24 ± 1 °C, 65 ± 10% RH and a 14:10 photoperiod. Longevity, intrinsic rate of natural increase (r m), net reproductive rate (R0), mean generation time (T), doubling time (DT), and finite rate of increase (&amp;#955;) of the bird cherry-oat aphid on the different cereal crops were estimated. Differences in fertility life table parameters of R....
Tipo: Journal article
Palavras-chave: Intrinsic rate; Life span; Bird cherry-oat aphid; Winter crops.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300007

Chemical properties of volcanic soil affected by seven-year rotations
Provedor de dados: 117
Autores: Hirzel,Juan; Undurraga,Pablo; González,Jorge.
Long-term crop rotation systems can benefit soil chemical-physical properties and crop productivity. The lack of information on the effect of long-term crop rotations on soil chemical-physical properties for volcanic soils in Chile could restrict reaping real benefits, and make it difficult to take agricultural management decisions, which could lead to possible negative consequences on some soil chemical-physical properties and the environment. The development of information associated with the effect on soil chemical-physical properties with respect to long-term rotation systems and their fertilization management contribute to improving agronomic management decisions for these soils. A study was carried out to assess the effect of six rotation systems...
Tipo: Journal article
Palavras-chave: Crop rotation; Andisol; Nutrient management; Soil fertility.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200016

Genetic Analysis of Relative Cell Injury Percentage and Some Yield Contributing Traits in Wheat Under Nomral and Heat Stress Conditions
Provedor de dados: 117
Autores: Farooq,Jehanzeb; Khaliq,Ihsan; Kashif,Muhammad; Ali,Qurban; Mahpara,Shahzadi.
Several wheat genotypes were screened against heat stress. Seven wheat (Triticum aestivum L.) cultivars obtained after screening against heat classified as tolerant, moderately tolerant, and susceptible to heat stress, were mated in a complete diallel mating system to study the inheritance pattern of relative cell injury percentage (cell injury %) and some yield contributing parameters under normal and heat stress conditions. Significant genotypic differences were found (P &lt; 0.01) for all the studied traits under both regimes. The scaling test disclosed partial adequacy for traits such as days to heading and days to maturity, but for flag leaf area and relative cell injury %, it showed full sufficiency under both environments. The model for grain yield...
Tipo: Journal article
Palavras-chave: Relative cell injury percentage; Additive components; Adequacy test; Heritability; Wheat; Diallel.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400003

Flaxseed Response To N, P, and K Fertilization in South Central Chile
Provedor de dados: 117
Autores: Berti,Marisol; Fischer,Susana; Wilckens,Rosemarie; Hevia,Felicitas.
Flaxseed (Linum usitatissimum L.) is a minor crop in Chile. There is interest to increase the number of crops on the current rotation in South Central Chile and also to increase oilseed feedstocks for salmon feed. There is little information published about seed yield and oil content response to N, P, and K fertilizers on flaxseed in Chile. The objective of this study was to determine the effect of N, P, and K fertilization on flaxseed yield, oil content, and composition. The study was conducted at two locations during two growing seasons (environments), in Chillán 2004-2005, 2005-2006, and in Osorno 2004-2005, 2006-2007. Treatments were four levels of N (0, 100, 200, and 300 kg N ha-1), three levels of P (0,100, and 200 kg P2O5 ha-1), and two levels of K...
Tipo: Journal article
Palavras-chave: Seed yield; Oil content; Oil composition; A-linolenic acid.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200003

Kinetic Study of Convective Drying of Blueberry Variety O’neil (Vaccinium corymbosum L.)
Provedor de dados: 117
Autores: Vega-Gálvez,A; Lemus-Mondaca,R; Tello-Ireland,C; Miranda,M; Yagnam,F.
The aim of this research was to study and to model the drying kinetics of the blueberry Vaccinium corymbosum L.) at three temperatures (60, 70 and 80 ºC) with an airflow of 2.0 ± 0.2 m s-1. Modeling of the desorption isotherm was carried out with the GAB (Guggenheim, Anderson and de Boer) equation, showing a good fit to experimental moisture data, giving as a result a monolayer moisture level of 0.084 g water g-1 dm. Newton, Henderson-Pabis, Page, Modified Page and Logarithmic mathematical models were applied in the study and in the modeling of the drying kinetics of this fruit. Kinetic parameters k of each model showed dependence on temperature, and were evaluated by an Arrhenius-type equation, with an activation energy of between 36.2 and 54.5 kJ mol-1....
Tipo: Journal article
Palavras-chave: Blueberry; GAB; Drying; Modeling; Statistical tests.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200006

Combining Ability Analysis for Achene Yield and Related Traits in Sunflower (Helianthus annuus L.)
Provedor de dados: 117
Autores: Waqas Ahmad,Muhammad; Shahzad Ahmed,Muhammad; Nadeem Tahir,Hammad.
Ten sunflower (Helianthus annuus L.) lines, five testers, and 50 crosses developed in line x tester fashion were evaluated for general combining ability (GCA) and specific combining ability (SCA) effects in a triplicate randomized complete block design, in Faisalabad, during 2009-2010. Genetic variability among genotypes was assessed for days to flowering, days to maturity, plant height, internodal length, leaf area, number of leaves per plant, head diameter, stem girth, percentage of filled achenes, 100 achene weight, achene yield per plant. A-1, A-7, A-27 and A-39 had significant general combining ability effects for days to flowering, days to maturity, internodal length, leaf area, and achene yield per plant. Among testers, A-26 and HBRS-1 were good...
Tipo: Journal article
Palavras-chave: GCA; SCA; Line x tester and yield.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100004

Effect of Culture Medium in Callogenesis from Adult Walnut Leaves (Juglans regia L.)
Provedor de dados: 117
Autores: Avilés,Fabiola; Ríos,Darcy; González,Ricardo; Sánchez-Olate,Manuel.
To define preliminary aspects of walnut (Juglans regia L.) callogenesis in indirect propagation systems, this work analyzed callogenic induction in adult leaves of walnut in broadleaf trees (BTM), Murashige and Skoog (MS) Driver Kuniyuki Walnut (DKW) and Woody Plant (WPM) media. Leaf segments of 1 cm², previously sterilized, were placed in each culture medium, supplemented with 21.4 µM naphtalene acetic acid (NAA) and 8.8 µM 6-benzylaminopurine (BAP). A completely random design was used; the experimental unit was a Petri dish with six callus explants. Each treatment was composed of seven Petri dishes. Callogenesis (%), nodular calli (%) and histology of calli explants were evaluated at 4 weeks by staining 10 µm slices with safranine-fastgreen. There were...
Tipo: Journal article
Palavras-chave: Auxins; Citoquinines; Walnut; Callus; Leaves.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300020

Impact of insecticides used to control Spodoptera frugiperda (J.E. Smith) in corn on survival, sex ratio, and reproduction of Trichogramma pretiosum Riley offspring
Provedor de dados: 117
Autores: Souza,Jander R; Carvalho,Geraldo A; Moura,Alexandre P; Couto,Marcelo H.G; Maia,Jader B.
Corn (Zea mays L.) is cultivated in large areas and considered one of the world's major cereal crops. There are several arthropod pests that can reduce its production such as the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lep.: Noctuidae), which is considered to be the main pest for corn. Fall armyworm is primarily controlled by insecticides. The use of biological control agents to manage this pest is growing with an emphasis on the egg parasitoid Trichogramma pretiosum Riley (Hym.: Trichogrammatidae). Thus, the aim of this research was to evaluate the impact of the following insecticides (g ai L-1) beta-cypermethrin (0.03), chlorfenapyr (0.60), chlorpyrifos (0.96), spinosad (0.16), etofenprox (0.10), triflumuron (0.08),...
Tipo: Journal article
Palavras-chave: Integrated pest management; Parasitoid; Selectivity; Triflumuron; Zea mays.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000200006

Effect of Pressure on the Quality of Pesticide Application in Orchards
Provedor de dados: 117
Autores: Di Prinzio,Alcides; Behmer,Sergio; Magdalena,Jorge; Chersicla,Germán.
Only part of the active ingredient used in agrochemical applications in orchards is retained on the trees. The product that is not retained is lost as sedimentation in the soil and as drift, the latter being a major source of environmental pollution. Unfavorable atmospheric conditions affect the uniformity of distribution and increase product loss. This can be mitigated by the utilization of larger drops. The objective of the present work was to evaluate the effect of service pressure on distribution in the trees and product loss by using a conventional hydro pneumatic sprayer. A fluorescent tracer was applied on fruit trees by an airblast sprayer, with two treatments: high pressure (1800 kPa) and low pressure (500 kPa). Samples were collected from the...
Tipo: Journal article
Palavras-chave: Orchards; Sprayers; Drift; Service pressure.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400020

Diversity of Genetic Resources and Genetic Association Analyses of Green and Dry Chillies of Eastern India
Provedor de dados: 117
Autores: Chattopadhyay,Arup; Baran Sharangi,Amit; Dai,Nuka; Dutta,Subrata.
Chilli (Capsicum annuum L.) is regarded as one of the main commercial vegetable and spice crops at the global level. Maximum diversity can be noted among the cultivars/landraces available in India with respect to shape, size, yield, quality, and other traits. The present experiment was conducted to identify the most promising chilli variety suited for green and dry purposes, to study the genetic variability for different traits and to assess the association of different yield attributing traits with the green and dry yield of chilli. Thirty four genotypes were characterized during a 2-yr period. Most of the genotypes possessed the character constellation of C. annuum. Two genotypes, ‘Chaitali Pointed’ and ‘BC CH Sel-4’ were found most promising with...
Tipo: Journal article
Palavras-chave: Quantitative traits; Qualitative traits; Genetic variability; Heritability; Selection index.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300002

Genetic Structure and Diversity of Four Chilean Sheep Breeds
Provedor de dados: 117
Autores: de la Barra,Rodrigo; Uribe,Héctor; Latorre,Etel; San Primitivo,Fermín; Arranz,Juan.
Chilean sheep breeds have a significant founder effect since they descend from very few parents, in some cases population inbreeding has increased and in others there have been significant differentiation processes as compared to their original population. The objective of this study was to estimate the current status of genetic diversity in sheep herds, which comprise the main sheep breeds in Chile, using molecular methods. Animals from four breeding herds were sampled and analyzed. The breeds studied were Corriedale, Suffolk Down, Romney Marsh and Chilota, these are the predominant numerical pure breeds in Chile. From each breed population 40 animals were sampled. Genetic characterization was done using nine microsatellite molecular markers (SSR)...
Tipo: Journal article
Palavras-chave: Microsatellite; Diversity; Sheep; Chile.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400016

Non-Parametric Statistical Methods and Data Transformations in Agricultural Pest Population Studies
Provedor de dados: 117
Autores: Cabrera Campos,Alcides; Guerra Bustillo,Caridad W; Herrera Villafranca,Magaly; Suris Campos,Moraima.
Analyzing data from agricultural pest populations regularly detects that they do not fulfill the theoretical requirements to implement classical ANOVA. Box-Cox transformations and nonparametric statistical methods are commonly used as alternatives to solve this problem. In this paper, we describe the results of applying these techniques to data from Thrips palmi Karny sampled in potato (Solanum tuberosum L.) plantations. The X² test was used for the goodness-of-fit of negative binomial distribution and as a test of independence to investigate the relationship between plant strata and insect stages. Seven data transformations were also applied to meet the requirements of classical ANOVA, which failed to eliminate the relationship between mean and variance....
Tipo: Journal article
Palavras-chave: Kruskal-Wallis test; Negative binomial distribution; Box-Cox transformations; Thrips palmi; Solanum tuberosum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300020

Weed Dynamics in Wheat-Canola Intercropping Systems
Provedor de dados: 117
Autores: Naeem,Muhammad; Ata Cheema,Zahid; Ahmad,Azraf-ul-Haq; Wahid,Abdul; Kamaran,Muhammad; Arif,Muhammad.
Weeds cause huge losses due to their competition with crops. Intercropping of wheat (Triticum aestivum L.) with canola (Brassica napus L.) under different spatial arrangements was evaluated for their effects on weeds and interaction between the crops at the Agronomic Research Area, University of Agriculture, Faisalabad, Pakistan, during 2009-2010. The treatments included wheat (line sowing), canola (line sowing), wheat (broadcast method), one row of wheat + one row of canola (30 cm apart), two rows of wheat + two rows of canola (45 cm apart), four rows of wheat + four rows of canola (75 cm apart) and mixed cropping of wheat + canola (broadcast method). The results revealed that all intercropping treatments significantly affected weed density and dry weight...
Tipo: Journal article
Palavras-chave: Intercropping; Brassica napus; Triticum aestivum; Weeds.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300019

Mycorrhizal Propagule Persistence in a Succession of Cereals in a Disturbed and Undisturbed Andisol Fertilized with Two Nitrogen Sources
Provedor de dados: 117
Autores: Cornejo,Pablo ; Rubio,Rosa ; Borie,Fernando .
Arbuscular mycorrhizal fungi (AMF) form symbiosis with plant roots, improving its establishment, nutrition, and tolerance to adverse soil conditions. In annual crop rotations, some aspects such as the type of N fertilizer and tillage system used can affect the AMF propagule density and its functionality in the following crop. To analyze the effect of the agronomic practices previously mentioned on the persistence and density of AMF propagules, a study in a succession of cereals was carried out. For this, soil previously cropped with wheat (Triticum aestivum L.) and fertilized with urea (NH4+) or sodium nitrate (NO3-) was disturbed in each case by simulating conventional tillage (CT) or maintained without disturbing, simulating no-tillage (NT). It was then...
Tipo: Journal article
Palavras-chave: Arbuscular mycorrhiza; Mycorrhizal propagules; Soil disturbing; Soil pH; Wheat-oat succession.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300016

Soil properties influencing phytoparasitic nematode population on Chilean vineyards
Provedor de dados: 117
Autores: Fajardo P,Mario; Aballay E,Erwin; Casanova P,Manuel.
Lifecycle of phytoparasitic nematode takes place in the rhizosphere, therefore their breeding, parasitism and mobility dynamics are inevitably influenced by the soil-root interaction, A study was performed to evaluate the influence of Vitis rootstocks to some plant parasitic nematodes under different soil conditions. Nematode populations were assessed in Vitis vinifera L. var ‘Chardonnay’ plants grafted on two rootstocks (K5BB, SO4) and ungrafted ‘Chardonnay’ as a control in three diferent alluvial soils in the central zone of Chile. Soils were two Inceptisols of the Casablanca Valley (Valparaíso Region), the first one without soil structure and with a densification zone in depth (S1) and the second one with sandy textural class (S3). A third soil was a...
Tipo: Journal article
Palavras-chave: Nematodes; Rootstocks; K5BB; SO4; Chardonnay; Rizosphere soil.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200009

Hommage to Dr. Norman E. Borlaug
Provedor de dados: 117
Autores: Mellado Z,Mario.
Tipo: Journal article
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300001

Phosphate Solubilizers from the Rhizosphere of Piper nigrum L. in Karnataka, India
Provedor de dados: 117
Autores: Seshachala,Usha; Tallapragada,Padmavathi.
Black pepper (Piper nigrum L.) is a climbing vine known for its pungent fruit used as a spice worldwide. The aim of this study was to evaluate the available P content in the native soils where pepper is grown as a crop plant. The native population of phosphate solubilising microbes (PSM) was studied from the rhizosphere of P. nigrum plants grown in the Western Ghats of Karnataka, India. A variety of phosphate solubilising bacteria and fungi were isolated from the rhizosphere soil samples. Phosphate solubilising capacity of different isolates was studied on Pikovskaya's medium. The isolates were tested for their phosphate solubilising capacity in vitro with three different phosphate sources, tricalcium phosphate (TCP), potassium dihydrogen phosphate (KHP),...
Tipo: Journal article
Palavras-chave: Aspergillus; Bacillus phosphate solubilising microbes 16s rDNA analysis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300014

Expression of LHC Genes and their Relation to Photo-Oxidative Stress Tolerance Tolerance in Solanum lycopersicum L. and Solanum chilense (Dunal) Reiche
Provedor de dados: 117
Autores: Chilian,Javier; Verdugo,Isabel; Poblete,Fernando; Ruiz-Lara,Simón; Casaretto,José A; González,Enrique.
Simultaneous exposition to low temperature and high light radiation cause photoinhibition of photosynthetic apparatus, affecting the productivity and geographical distribution of agricultural crops. In several Solanaceous species, tolerance to low temperature stress in combination with high light has been associated with some stimulation in non-photochemical quenching (NPQ), which involved reorganization in light-harvesting complex (LHC) proteins. To study photosynthetic performance in Solanum lycopersicum L. and S. chilense (Dunal) Reiche, and to investigate transcriptional regulation of genes encoding LHC proteins and their involvement in the NPQ, plants of both species were exposed to low temperature (4 °C) and high light radiation (1300 /&lt;mol m-2...
Tipo: Journal article
Palavras-chave: Lipid-peroxidation; Photoinhibition; Photochemical quenching; Zeaxanthin.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400002

Udder Morphological Traits and Milk Yield of Chilota and Suffolk Down Sheep Breeds
Provedor de dados: 117
Autores: Martínez,María E; Calderón,Cecilia; de la Barra,Rodrigo; de la Fuente,L. Fernando; Gonzalo,Carlos.
Morphological traits of the whole udder (circumference, width, height, and length), teats (angle, length and width), udder cistern (teat opening and cistern height), and milk yield were measured over one lactation in a total of 18 ewes (nine Chilota and nine Suffolk Down sheep) belonging to the same experimental flock (Centro Experimental INIA Butalcura, Chiloé, Chile). Analysis of variance showed significant effects for breed, sheep within breed, and stage of lactation. Chilota ewes evidenced greater udder circumference (433 mm), udder length (86 mm), teat opening (96º), and milk yield (947 mL d-1) than Suffolk Down ewes (410 mm, 77 mm, 93º, and 559 mL d-1, respectively). Udder circumference, udder width, udder length, cistern height and teat size...
Tipo: Journal article
Palavras-chave: Mammary morphology; Teats; Dairy; Sheep.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100011

Light quality management in fruit orchards: physiological and technological aspects
Provedor de dados: 117
Autores: M. Bastías,Richard; Corelli-Grappadelli,Luca.
Light quality (sunlight spectrum) management promises to provide a new technological alternative to sustainable production in horticultural crops. However, little information exists about physiological and technological aspects on light quality management in fruit crops. Sunlight composition changes widely in orchard canopies, inducing different plant responses in fruit trees mediated by phytochrome (PHY) and cryptochrome (CRY) activity. High proportion of far-red (FR) in relation to red (R) light increases shoot elongation, while blue (B) light induces shoot dwarfing. Red and ultraviolet (UV) light increases fruit skin anthocyanin synthesis, while FR light shows a negative effect. Red and B light can also alter leaf morpho-physiological traits in fruit...
Tipo: Journal article
Palavras-chave: Red; Far-red and blue light; Phytochrome; Cryptochrome; Photo-morphogenesis; Reflective films; Colored nets.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400018

Phosphorus absorption and use efficiency by Lotus spp. under water stress conditions in two soils: A pot experiment
Provedor de dados: 117
Autores: Castillo,Carolina; Acuña,Hernán; Zagal,Erick; Inostroza,Luis.
The response to P and water deficiencies of forage Lotus species has not been sufficiently studied in the Andisol and Vertisol soil orders in Chile's marginal areas. A pot experiment under cover was carried out between October 2007 and March 2008 to study the effects of P and soil water availability (SWA) on DM production, P absorption, and P use efficiency in Lotus spp. The experiment included three Lotus (L. corniculatus L., L. tenuis Waldst. &amp;amp; Kit. ex Willd., and L. uliginosus Schkuhr) species, two soils (Andisol and Vertisol), two contrasting P levels (low and high), and two SWA levels (10% and 100%). A completely randomized design with a 3 x 2 x 2 x 2 factorial arrangement with four replicates was used. Accumulated shoot and root DM, P...
Tipo: Journal article
Palavras-chave: Lotus spp.; Volcanic soils; Clay soils; Mycorrhizal colonization.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100005

Sensitivity and Variability of Two Plant Water Stress Indicators: Exploring Criteria for Choosing a plant Monitoring Method for Avocado Irrigation Management
Provedor de dados: 117
Autores: Celedón,José M; Gil,Pilar M; Ferreyra,Raul; Maldonado,Patricio; Barrera,Cristián.
Avocado (Persea americana Mill.) is a fruit-tree species highly susceptible to water deficit, which makes irrigation management a difficult task for growers. When irrigation is inadequate, trees suffer growth reduction, fruit losses, and roots damage. This study addressed the question of how to assess water stress in avocado trees and the considerations to choose an indicator to measure the plant water stress. In this work the sensitivity and variability of two water stress indicators in response to water deficit were analyzed: stem water potential (SWP) and maximum daily trunk shrinkage (MDTS). During a period of high water demand, avocado trees planted in a clay loam soil were subjected to water stress by withholding irrigation and compared to control...
Tipo: Journal article
Palavras-chave: Dendrometers; Stem water potential; Environmental stress; Persea americana.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300012

Decomposition of the Rubber Tree Hevea brasiliensis Litter at Two Depths
Provedor de dados: 117
Autores: Gréggio,Thiago Claudino; Assis,Luiz Carlos; Nahas,Ely.
The decomposition of soil litter contributes to maintaining agricultural sustainability, since the nutrients released by microbial activity are determinants of the net productivity of the agroecosystem. The decomposition of rubber tree (Hevea brasiliensis [Willd. ex A. Juss.] Müll. Arg.) leaves located on the surface and buried in at 10 cm depth in Forest and Savannah (Cerradão) soils (Oxisols) was studied, with emphasis on the production of CO2 and the monthly variation of the remaining amounts of litter mass, soluble substances, cellulose and lignin. To evaluate CO2 production, H. brasiliensis leaves were incubated for 30 days in soils from the 0-2 cm and 10-12 cm layers. CO2 production increased in the 0-2 cm layer in comparison to the 10-12 cm layer....
Tipo: Journal article
Palavras-chave: Litter mass; Cellulose; Lignin; Soluble substances; Litter-bags.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200002

Faraón-INIA, a new Winter Triticale (×Triticosecale Wittmack) for Southern Chile
Provedor de dados: 117
Autores: Jobet,Claudio; Matus,Iván; Campillo,Ricardo; Romero,Oriela; Madariaga,Ricardo; Alfaro,Cristian.
Faraón-INIA is a new winter triticale (×Triticosecale Wittmack) cultivar released by the National Wheat Program of the Instituto de Investigaciones Agropecuarias INIA in Chile. It is derived from an F9 material received from Nordsaat, Germany, under a germplasm exchange agreement signed in 2006 by both institutions. The crossing was Piano/Focus with Nord93.7548 pedigree. Faraón-INIA has a winter growth habit, a short stem (semi-dwarf), with a mean height of 106 cm. The spike is long, compact, decumbent, white, and awned. The grain is soft, yellow, with 1000-grain weight of 36 g, and a mean of hectoliter weight of 76 kg hL-1. It is resistant to stripe rust (Puccinia striiformis West. f. sp. tritici) and leaf rust (Puccinia triticina Erikss.) as well as...
Tipo: Journal article
Palavras-chave: Winter triticale; High-yielding cultivar; Quality.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400019

Comparison and Characterization of Garlic (Allium sativum L.) Bulbs Extracts and Their Effect on Mortality and Repellency of Tetranychus urticae Koch (Acari: Tetranychidae)
Provedor de dados: 117
Autores: Hincapié Ll,Carlos Augusto; López P,Gloria Eugenia; Torres Ch,Ricardo.
Tetranychus urticae Koch is a pest that causes great economic losses because it attacks a wide range of host plants. Also, some populations have developed resistance against commercial acaricides. This work compares different extracts from garlic (Allium sativum L.) bulbs measuring their toxicity and repellency effects on T. urticae. Extracts were obtained using as solvents CO2 in supercritical conditions (CSC), ethanol and petroleum ether using soxhlet and soaking methods and soaking in water. The supercritical fluid extraction technique allows for obtaining extracts at low temperature using high pressures, avoiding compound degradation and making possible solvent separation by exposing the extract at room temperature. Mites were bred on bean plants...
Tipo: Journal article
Palavras-chave: Two-spotted spider mite; Plant extracts; Miticidal effect; Liliaceae.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400001

Valinia INIA, a New Early Storage Onion Variety for Central South Chile
Provedor de dados: 117
Autores: González A,María Inés; Herrera V,Patricia.
In Central South Chile, storage onion varieties (Allium cepa L.) sold domestically usually begin the maturation process in March, which implies that a large proportion of bulbs do not mature adequately and do not resist prolonged storage. This situation led the Quilamapu vegetable program of the Instituto de Investigaciones Agropecuarias INIA to select an early maturing onion variety. This breeding method involved a recurrent selection with free plant crossing that began in 1994 on a population of 2000 plants of the 'Valenciana' commercial variety. Plants were first selected when they reached physiological maturity (tops down before 28 February), and then for shape, size, storage capacity, and single-centered bulbs. The result of the program was 'Valinia...
Tipo: Journal article
Palavras-chave: Cultivar; Precocity; Storage capacity; Single center.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100003

Glycogen Determination in Bovine Muscle: A Proposal for Rapid Determination
Provedor de dados: 117
Autores: Hargreaves B,Antonio; Barrales V,Luis; Barrales Z,Daniela; Riveros F,José Luis; Peña R,Iván.
A practical, rapid and inexpensive method for muscle glucose determination is proposed. The method is based on acid digestion of the sample, followed by neutralization of the solution and the subsequent glucose determination using a domestic glucometer for human blood glucose level control. In a pre-experimental phase, the accuracy of this methodology and the titration method was determined, comparing results to pre-established glucose concentrations. There were significant differences between the glucose reading given by the glucometer and the pre-established glucose concentrations and the results given by the titration method. Nevertheless, when discrepancies (bias) were identified, differences resulted non-significant (P = 0.85). Subsequently, muscle...
Tipo: Journal article
Palavras-chave: Muscle; Glucose; Glycogen; Titration; Glycolytic potential.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300009

Alstroemeria presliana Herb. (Alstroemeriaceae) in Chile from a Cytogenetic Perspective
Provedor de dados: 117
Autores: Baeza,Carlos M; Schrader,Otto; Ruiz,Eduardo; Negritto,M.
Alstroemeria (Alstroemeriaceae) is an endemic genus of South America with two major distribution centers in the continent: Chile and Brazil. In Chile the genus is distributed from the North, near Iquique (20º13’ S, 70º09’ W) to the Chilean and Argentine Patagonia (53º10’ S, 70º54’ W). The central zone of Chile presents the highest number of species. A. presliana Herb. grows from Curicó (34º59’ S, 71º14’ W) to Cautín (38º45’ S, 72º34’ W) in Chile and Neuquén (36º50’ S, 71º05’ W), Argentina. A comparative karyotype study was made between a population of A. presliana subsp. presliana and a population of A. presliana subsp. australis Ehr. Bayer. Both populations presented asymmetric karyotypes, with 2n = 2x = 16 chromosomes, but with different chromosome...
Tipo: Journal article
Palavras-chave: Alstroemeriaceae; Karyotype; Chromosome numbers; Chile.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400002

Effects of Nitrate and Labile Carbon on Denitrification of Southern Temperate Forest Soils
Provedor de dados: 117
Autores: Pérez,Cecilia A; Carmona,Martín R.; Fariña,José M.; Armesto,Juan J.
The pressure for anthropogenic land use changes and logging of temperate forests in southern Chile is rapidly increasing, with its potentially high impacts on the capacity of soils to retain important limiting elements. We tested the hypotheses that logging increases the denitrification rates and nitrate and C limitation of denitrifiers activity would be higher in soils of unlogged, old-growth forests than in soils of logged forests. Potential denitrification rates were estimated by the acetylene inhibition assay in intact soil cores in laboratory short-term aerobic incubations using the following treatments: 0.7 mmol NO3-N addition, the same nitrate addition plus 23.3 mmol C-glucose, and controls (no additions) with and without 10% v/v acetylene. Forest...
Tipo: Journal article
Palavras-chave: Acetylene inhibition assay; Lowland evergreen forests; Selective logging; Nitrogen availability.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200008

Effect of Agricultural Intervention on the Spatial Variability of some Soils Chemical Properties in the Eastern Plains of Colombia
Provedor de dados: 117
Autores: Camacho-Tamayo,Jesús H; Luengas,Carlos A; Leiva,Fabio R.
Growing demand for food exerts pressure on natural resources and may lead to the expansion of agricultural frontiers in developing countries. Most of this pressure appears in tropical zones, in native savannahs, with naturally infertile soils prone to degradation. Crop management in these regions is based on generalized estimates, leaving aside the inherent soil variability, leading to low production efficiency and high risk of environmental damage. This study aims at determining the spatial variability of some chemical properties, including organic carbon, pH, exchangeable acidity, exchangeable aluminum, P, Ca, Mg, K and Na for two Oxisols with different levels of agricultural intervention, in Puerto Lopez, Colombia, in order to identify guidelines for...
Tipo: Journal article
Palavras-chave: Geostatistics; Kriging; Soil management; Precision agriculture; Kriging.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100005

Phytochemical Evaluation of Wild and Cultivated Pepper (Capsicum annuum L. and C. pubescens Ruiz &amp;amp; Pav.) from Oaxaca, Mexico
Provedor de dados: 117
Autores: Vera-Guzmán,Araceli Minerva; Chávez-Servia,José Luis; Carrillo-Rodríguez,José Cruz; G. López,Mercedes.
Reports of the last decade show that some types of food and spices included in the human diet, such as pepper (Capsicum annuum L.) can have a positive effect on human health. The Mexican pepper germplasm is poorly documented with regard to variety and the amount of phytochemical compounds that it contains. In the present study, the variation of phytochemical compounds was evaluated in nine fruit variants (morphotypes) of wild and cultivated pepper grown in Oaxaca. ANOVA detected significant differences among pepper morphotypes and ripeness stages of fruits; vitamin C, total phenols, flavonoids, P-carotene, coordinated chromatic of color, and capsaicinoids. The highest values of vitamin C were found in 'Tabaquero', 'Guero' and 'Costeño' morphotypes (151.6...
Tipo: Journal article
Palavras-chave: Capsaicionids; Carotenoids; Phenols; Flavonoids; Vitamin C.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400013

Short Term Impact of the Chilean Journal of Agricultural Research: A Bibliometric Analysis
Provedor de dados: 117
Autores: Krauskopf,Erwin.
In January 2007, the Chilean Journal of Agricultural Research was indexed by the Institute of Scientific Information (ISI). This paper reviews the research that has been published since 2007 by using records extracted from the Web of Science database. The papers published were mostly affiliated to researchers from Chile, and six out of the ten most-contributing countries were from Latin America. The analysis by institutions showed Universidad de Concepcion as the most prolific, although this result is not valid. A lack of standardization in the manner the Instituto de Investigaciones Agropecuarias (INIA) subscribed its address on each paper caused a disaggregation of the information. This was proven by the manual curation of each record that was affiliated...
Tipo: Journal article
Palavras-chave: Bibliometric; Epistemometry; Scientific productivity; Chile.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100026

Invasiveness of Cut-Leaf Ground-Cherry (Physalis angulata L.) Populations and Impact of Soil Water and Nutrient Availability
Provedor de dados: 117
Autores: Travlos,Ilias S.
Biological invasions are a major threat to natural ecosystems and agroecosystems, while weed flora is noticeably changing globally. In this study we evaluated the potential of cut-leaf ground-cherry (Physalis angulata L.), a species native to America, to invade the semi-arid regions of Greece. Greenhouse and laboratory experiments were conducted to evaluate the effects of different environmental resources (nutrient and water availability) on seedling growth, biomass production, fecundity, and seed germination of four populations of cut-leaf ground-cherry. Our results suggest that cut-leaf ground-cherry does not tolerate extreme drought during the first growth stages, while it can survive and produce adequate and rapidly germinated seed (&gt; 85%) under low...
Tipo: Journal article
Palavras-chave: Physalis angulata; Invasion; Greece; Water stress.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300009

Genetic variation within three populations of Phycella australis (Phil.) Ravenna from Biobío Region, Chile, evaluated using ISSR markers
Provedor de dados: 117
Autores: Flores,Cristian; Delaveau,Catherine; Alvarez,Carolina; Vergara,Dafne; Baeza,Carlos; Ruiz,Eduardo; Uribe,Matilde.
Phycella australis (Phil.) Ravenna is a Chilean plant with high ornamental potential; however, the intensive extraction as a cut flower might be detrimental for the conservational state by ignoring the state of genetic variation. The objective of this investigation was to assess genetic variability within and between three populations of P. australis in the Biobío Region using inter-simple sequence repeat (ISSR) markers. The evaluated areas correspond to three locations in the province of Concepción, Biobío Region: Desembocadura (36°48' S, 73°10' W), Santa Juana (36°58' S, 72°58' W), and Lipinhue (37°00' S, 72°58' W). Six ISSR primers were used obtaining 51 fragments, from which 72.5% were polymorphic. From the three evaluated sites Santa Juana showed a...
Tipo: Journal article
Palavras-chave: Amaryllidaceae; Genetic variability; Molecular marker; Ornamental plant.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100012

Technological Change and Technical Efficiency for Diary Farms in Three Countries of South America
Provedor de dados: 117
Autores: Bravo-Ureta,Boris E; Moreira,Víctor H; Arzubi,Amilcar A; Schilder,Ernesto D; Álvarez,Jorge; Molina,Carlos.
The progressive liberalization of agricultural markets, along with the threat that imported products can pose to local producers, reveals the importance of productivity growth as a mechanism to improve competitiveness. Technical efficiency measurement is the most studied component of productivity because it can help to generate valuable information for policy formulation and farm level decisions focused on the improvement of farm performance. This study uses unbalanced panel data sets for dairy farms from Argentina, Chile and Uruguay, to estimate stochastic production frontier models. These frontiers are then used to estimate economies of size, technological change and technical efficiency. All estimations are based on the Battese and Coelli (1992) model,...
Tipo: Journal article
Palavras-chave: Stochastic frontiers; Dairy farms; Argentina; Chile; Uruguay.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400006

Implementation of a Molecular System for Traceability of Beef Based on Microsatellite Markers
Provedor de dados: 117
Autores: Felmer D,Ricardo; Sagredo D,Boris; Chávez R,Renato; Iraira H,Sergio; Folch M,Carolina; Parra G,Lorena; Catrileo S,Adrián; Ortiz L,Manuel.
Animal products traceability has acquired considerable importance as a security measure in EEC member countries since the food crisis of the mid-nineties. This has led to reinforcing the capacity to manage cattle product quality, with traceability emerging as the main tool to prevent risks to product security and quality as demanded by consumers in developed countries. The practical application of a traceability system for beef, based on molecular markers requires the election of a panel of microsatellites, as well as the optimization of methods of sampling and DNA analysis. In this work, a traceability system for beef based on a panel of 10 microsatellites markers was implemented. Different biological samples were evaluated, such as hair, blood, tissue...
Tipo: Journal article
Palavras-chave: Traceability; Microsatellites; Individual identification; Beef.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000400004

Green Index to Estimate Crop Nitrogen Status in Potato Processing Varieties
Provedor de dados: 117
Autores: Giletto,Claudia Marcela; Díaz,Cecilia; Rattín,Jorge Edgardo; Echeverría,Hernán Eduardo; Caldiz,Daniel Osmar.
Nitrogen is the most important nutrient in growing potatoes (Solanum tuberosum L.) because either a deficit or excess in its supply can affect yield and quality, resulting in economic losses. To make a rational use of this nutrient, it is necessary to monitor N status during crop development. The green index (IV) could be a valuable method to assess N sufficiency. In experiments with variable N supply, the IV was assessed during crop growth and an N sufficiency index was derived (ISN-IV). The relationship between tuber yield and the IV and ISN-IV was established, as well as the association between the IV and ISN-IV and N concentration in the following varieties: Innovator, Bannock Russet and Gem Russet. During the vegetative growth stage, the IV and ISN-IV...
Tipo: Journal article
Palavras-chave: Nitrogen; Chlorophyll meter; Potato varieties.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100015

Effects of Source and Rate of Nitrogen Fertilizer on Yield, Yield Components and Quality of Winter Rapeseed (Brassica napus L.)
Provedor de dados: 117
Autores: Öztürk,Özden.
Winter rapeseed (Brassica napus L.) has potential to become an alternate oilseed crop both for edible oil production and energy agriculture (biofuel production) for Turkey. This study was conducted to determine the effect of year, N sources and doses on the yield and quality traits of winter rapeseed in a cereal system in calcareous soils over two seasons, 2000-2001 and 2001-2002, in Central Anatolia. Three N sources, ammonium sulfate, ammonium nitrate and urea, were applied as hand broadcast on the soil surface at five doses (0, 50, 100, 150, and 200 kg N ha-1). The traits investigated were plant height, number of branches and pods per plant, number of seed per pod, thousand seed weight, seed yield, oil and protein content. There were significantly...
Tipo: Journal article
Palavras-chave: Winter rapeseed; Seed yield; Oil content; Protein content.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100014

Assessment of Blood Chemistry, Weight Gain and Linear Body Measurements of Pre-Puberal Buck Rabbits Fed Different Levels of Neem (Azadirachta indica A. Juss.) Leaf Meals
Provedor de dados: 117
Autores: Ogbuewu,I.P; Uchegbu,M.C; Okoli,I.C; Iloeje,M.U.
A 16 week feeding trial was carried out to investigate the effect of dietary Neem (Azadirachta indica A. Juss.) leaf meal (NLM) on body weight gain, linear body measurements and blood chemistry of pre-puberal buck rabbits. Four treatment diets were formulated to contain the NLM at inclusion levels of 0 (control), 5, 10 and 15%. Thirty six crossbred New Zealand white × Chinchilla pre-puberal buck rabbits aged 5 to 6 mo were divided into four groups of nine rabbits and each group was further replicated into three of three rabbits each. The rabbits were randomly assigned to the four dietary treatments. Lymphocyte count of rabbits fed control diet (8.32 × 10(9) mm-3) was significantly higher than the group fed 15% NLM (4.60 × 10(9) mm-3). The mean cell...
Tipo: Journal article
Palavras-chave: Neem leaf meal; Body weight gain; Blood chemistry; Linear body measurements; Buck rabbits.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300020

Dissolved Organic Carbon and Nitrogen in Andisol for Six Crop Rotations with Different Soil Management Intensity
Provedor de dados: 117
Autores: Undurraga D,Pablo; Zagal V,Erick; Sepúlveda W,Gloria; Valderrama V,Natalia.
Soil organic matter (OM) content is a quality indicator, but is an inadequate indicator in the short-term because these changes take place slowly, so dissolved organic components have emerged as an alternative. In volcanic soil subjected to different crop rotations with distinct land use intensity, dissolved organic C and N (DOC and DON) were determined as well as their relationship with total C and N contents in the soil, considering the effects of crop rotation, fertilization level, and soil depth. In humid samples of Humic Haploxerands collected at four depths up to 40 cm, DOC and DON contents were determined by extraction with K2SO4 and filtered. Results indicated interaction between the studied factors, DOC fluctuated between 67.8 and 151.7 mg kg-1...
Tipo: Journal article
Palavras-chave: Organic matter; Dissolved organic matter; Total C; Total N; Volcanic soil.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300018

Arrowleaf Clover (Trifolium vesiculosum Savi): A New Species of Annual Legumes for High Rainfall Areas of the Mediterranean Climate Zone of Chile
Provedor de dados: 117
Autores: Ovalle M,Carlos; del Pozo,Alejandro; Fernández,Fernando; Chavarría,Jorge; Arredondo,Susana.
The present review examines the main attributes and agronomic characteristics of arrowleaf clover (Trifolium vesiculosum Savi) and its incorporation into production systems in dryland areas of the Andean foothills of the humid Mediterranean climate zone of Chile. It is a new species of annual legume in Chile for light and medium textured soils. The root system can reach a depth of 1.5 m and its seeds have a high percentage of hardseedness (99.8%). It is an upright plant, with purplish-white flowers. The mature plant has large arrow-shaped leaves up to 50 mm long, often marked with a large white “V”. Dry matter and seed production in the Andean foothills is high (3.9-8.8 t DM ha-1 and 700-900 kg ha-1, respectively), surpassing the productivity of sub clover...
Tipo: Journal article
Palavras-chave: Arrowleaf clover; Annual legume pastures; Dryland Andean foothills; Mediterranean pastures.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100018

Seasonal Induction of Cluster Roots in Embothrium coccineum J.R. Forst. &amp;amp; G. Forst. in the Field: Factors that Regulate their Development
Provedor de dados: 117
Autores: Donoso-Ñanculao,Gabriel; Castro,Mauricio; Navarrete,Darío; Bravo,León A; Corcuera,Luis J.
Embothrium coccineum J.R. Forst. &amp;amp; G. Forst. (Proteaceae) is a tree that grows successfully in nutrient poor soils of southern Chile at full sunlight. Under these conditions it develops cluster roots (CR).However, the induction of CR on this species has not been studied completely. The aim of this work was to study the effect of seasonality, soil and weeds in the development of CR in E. coccineum. The present study was performed in Los Lagos Region (41º72’ S lat), Chile. Plants of E. coccineum were grown in sandy soils in presence or absence of weeds, using two concentrations of organic matter. The number of CR per plant, CR mass and P concentration in leaves was measured during the four seasons in E. coccineum plants. The CR development in the...
Tipo: Journal article
Palavras-chave: Cluster roots; Phosphorus deficiency; Root development.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400005

Effect of Quantity and Distribution of Rainfalls on Hordeum murinum L. Growth and Development
Provedor de dados: 117
The growth and development of Hordeum murinum L. seeds growing with extreme pluviometric regimes in cool greenhouse conditions were evaluated. Seven treatments according to quantity and distribution of real rainfalls of the semiarid zone of the Metropolitan Region, Chile were applied: rainy-late, normal-late, dry-early, rainy-normal, normal-early and dry-late, plus a reference without water stress, at 2/3 field capacity. The experimental design was randomized complete blocks with five replicate pots. Seeds produced in the last year were sown in pots with disinfected soil leaving the more uniform plants after emergence. Evaluations were made of phytomass production, spearing shoots of roots, the quantity of floral stems and seeds, their total weight and the...
Tipo: Journal article
Palavras-chave: Pluviometric regime; Reproductive efficiency; Naturalized poacea.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200008

Genetic Variability of the Tomato Leaf Miner (Tuta absoluta Meirick; Lepidoptera: Gelechiidae), in Tunisia, Inferred from RAPD-PCR
Provedor de dados: 117
Autores: Bettaibi,Asma; Mezghani-Khemakhem,Maha; Bouktila,Dhia; Makni,Hanem; Makni,Mohamed.
The tomato leaf miner Tuta absoluta Meyrick has invaded tomato (Solanum lycopersicum L.) crop in Tunisia since 2008 and is representing today a major threat to the production of this crop. In this study, we used the Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) technology to assess the genetic variability within and among seven populations of T. absoluta, collected on tomato from different regions in Tunisia. Using five RAPD-PCR primers and 108 individuals, 140 polymorphic fragments were recorded. From 335 different RAPD phenotypes generated, 71 were redundant and 264 unique to a specific population. The genetic structure of T. absoluta was investigated using analysis of molecular variance (AMOVA), genetic distances (Fst) and...
Tipo: Journal article
Palavras-chave: Invasive species; Molecular markers; Insect populations; Gene flow.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200008

Nymphicidal and Ovipositional Efficacy of Seaweed Sargassum tenerrimum (J. Agardh) against Dysdercus cingulatus (Fab.) (Pyrrhocoridae)
Provedor de dados: 117
Autores: Sahayaraj,Kitherian; Jeeva,Y. Mary.
We investigated the role of a brown seaweed alga, Sargassum tenerrimum (J. Agardh), against Dysdercus cingulatus (Fab.), which is an economically important cotton pest in many parts of Asia. Sargassum tenerrimum has been used as a source of fertilizers and drugs, but there is no information available in the literature about its use in ecofriendly pest management. The impact of benzene (BN), chloroform (CH), and a mixture of benzene and chloroform (BNCH) extracts, as well as two chromatographic fractions of BNCH (FR1 and FR2) were investigated for their insecticidal and ovipositional properties against D. cingulatus. The BE extract showed the best insecticidal activity (LC50 = 0.009%), higher than BNCH (LC50 = 0.021%) and CH extracts (LC50 = 0.2481%), and...
Tipo: Journal article
Palavras-chave: Cotton pest; Nymphicidal; Ovipositional; Seaweed; Pest management.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100024

Effect of breed and feeding on the carcass characteristics of the Chilote breed lamb
Provedor de dados: 117
Autores: Ramírez-Retamal,Jorge; Morales,Rodrigo; Martínez,M. Eugenia; de la Barra,Rodrigo.
The Chilote sheep has been developed in an isolated environment, based on grazing lands with low nutritive value belonging to small-scale producers, because of which there is little information about the use of this breed for meat production. The objective of this work was to determine the effects on lamb carcasses of two breeds with different productive purposes and fed on pastures with different nutritional quality. Three groups of lambs were used. The first and second groups were composed of 13 and 11 Chilote lambs respectively, and the third composed of six Suffolk Down lambs. Lambs remained with their mothers, the first group on naturalized pasture and the rest on rangeland. Animals were slaughtered at 90 d of age. Live weight, carcass weight and...
Tipo: Journal article
Palavras-chave: Lambs; Pasture; Carcass quality; Meat yield.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100007

Cracking in sweet cherries: A comprehensive review from a physiological, molecular, and genomic perspective
Provedor de dados: 117
Autores: Balbontín,Cristián; Ayala,Héctor; M. Bastías,Richard; Tapia,Gerardo; Ellena,Miguel; Torres,Carolina; Yuri,José Antonio; Quero-García,José; Ríos,Juan Carlos; Silva,Herman.
Rain-induced cracking in fruits of sweet cherry (Prunus avium L.) is a problem in most producing areas of the world and causes significant economic losses. Different orchard management practices have been employed to reduce the severity of this problem, although a complete solution is not yet available. Fruit cracking is a complex phenomenon and there are many factors that seem to be involved in its development. During the last decade, genomic and biochemical approaches have provided new insights on the different mechanisms that could be involved in the differential susceptibility shown by commercial cultivars. For instance, sweet cherry genome and transcriptome sequencing information have provided new opportunities to study the expression and structure of...
Tipo: Journal article
Palavras-chave: Physiology; Functional genomics; RNA seq.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100010

Effect of Pollen from Different Plant Species on Development of Typhlodromus pyri (Sheuten) (Acari: Phytoseiidae)
Provedor de dados: 117
Autores: Bermúdez,Paulina; Vargas,Robinson; Cardemil,Antonieta; López,Eugenio.
Typhlodromus pyri (Sheuten) (Acari: Phytoseiidae) is a phytoseiid mite with a high potential in controlling the false Chilean mite (Brevipalpus chilensis Baker; Acari: Tenuipalpidae). The purpose of this study was to determine the effect of different plant species pollen as a complementary food in the development of T. pyri when its prey is in low levels of availability. Mites were individually placed on black plastic boxes with pollen and maintained at a temperature of 26 ± 2 °C, 70 ± 5% relative humidity (RH), and a photoperiod of 16:8 h (L:D). Postembryonic development of T. pyri was studied in 11 pollen species, as well as in a mixed diet of Hirschfeldia incana (L.) and B. chilensis. Results show that H. incana was the only pollen in which there was no...
Tipo: Journal article
Palavras-chave: Phytoseiid mite; Complementary food; Survival curve.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300008

Use of the Dynamic Model for the Assessment of Winter Chilling in a Temperate and a Subtropical Climatic Zone of Chile
Provedor de dados: 117
Autores: Pérez,Francisco J; Ormeño N,Juan; Reynaert,Bryan; Rubio,Sebastián.
Accumulated chilling was estimated by applying three different models to the hourly autumn-winter temperature records from Santiago (33°34 S lat; 625 m.a.s.l.) and Vicuña (30°02´ S lat; 643 m.a.s.l.) for the years 2005 and 2006. The model of chilling hours, currently used in Chile as an agroclimatic indicator, was of limited use for effectively contrasting a subtropical condition (Vicuña) with a temperate area such as Santiago. The application of the Utah model gave negative values from March to May, and even up to June in Vicuña, since in this model the chilling effect is “negated” by warmer temperatures. However, a modified version of the Utah model named Positive Chilling Units (PCU), in which negative values are omitted, showed differences in the...
Tipo: Journal article
Palavras-chave: Accumulated winter-chill; Bud dormancy; Dynamic model.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200010

Control of Botrytis cinerea in Eucalyptus globulus Mini-Cuttings Using Clonostachys and Trichoderma Strains
Provedor de dados: 117
Autores: Zaldúa,Salomé; Sanfuentes,Eugenio.
Botrytis cinerea Pers. ex Fr. causes the disease known as gray mold in more than 200 hosts. It is one of the most important pathogens in Chilean forest nurseries and Eucalyptus globulus Labill. is one of the most susceptible species, especially in vegetative reproduction systems. Clonostachys and Trichoderma strains were selected as potential biocontrol agents of gray mold in previous research by the authors. The objective of this study was to evaluate the effectiveness of antagonistic fungi to control B. cinerea in E. globulus mini-cuttings. Five fungi strains were tested and applied weekly, two Clonostachys and three Trichoderma (5 x 10(6) conidia mL-1). In addition, comparison treatments were also used: absolute control (water) and fungicide...
Tipo: Journal article
Palavras-chave: Biocontrol agents; Forest nurseries; Eucalyptus; Gray mold; Antagonistic fungi.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400007

Investigations of the Plum pox virus in Chile in the past 20 years
Provedor de dados: 117
Autores: Herrera,Guido.
Sharka disease, which is caused by Plum pox virus (PPV), is one of the most serious diseases affecting stone fruit trees around the world. Identified in Bulgaria in 1931, it was restricted to the European continent until 1992 when the virus was identified in Chile. It was subsequently verified in the USA, Canada, and Argentina. After 20 years since first detecting PPV in Chile, it seems clear that the disease cannot be eradicated in spite of various measures. Considering the seriousness of this problem for the domestic industry, a series of studies have been conducted to determine the distribution and degree of transmission of the disease, its biological and molecular characterization and epidemiological aspects, etc. The available information has allowed...
Tipo: Journal article
Palavras-chave: Sharka disease; Virus; Stone fruit.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100009

Nitrogen Losses under Different Cattle Grazing Frequencies and Intensities in a Volcanic Soil of Southern Chile
Provedor de dados: 117
Autores: Núñez,Pedro A.; Demanet,Rolando; Misselbrook,Tom H.; Alfaro,Marta; Mora,María de la Luz.
Chilean livestock production systems have intensified over the last years, with increasing amounts of N fertilizer inputs creating the potentiality for environmental damage through N pollution of water and air, so that alternative production strategies have been developed to reduce such environmental impacts. This study assesses N losses under different grazing frequencies and intensities on permanent pasture (Lolium perenne L., Festuca arundinacea Schreb., Dactylis glomerata L., and Trifolium repens L.) on an Andisol in Southern Chile. Four grazing strategies were evaluated: frequent-heavy (FH), frequent-light (FL), infrequent-heavy (IH), infrequent-light (IL), and a no grazing control (C) treatment, and each with three replicates in a randomized complete...
Tipo: Journal article
Palavras-chave: Ammonium; Grazing; Leaching; Nitrate; NH3 volatilization.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200007

Evaluation of a SCAR RYSC3 Marker of the Ry adg Gene to Select Resistant Genotypes to Potato Virus Y (PVY) in the INIA Potato Breeding Program
Provedor de dados: 117
Autores: Sagredo D,Boris; Mathias R,Mónica; Barrientos P,Claudia; Acuña B,Ivette; Kalazich B,Julio; Santos Rojas,José.
The Potato virus Y (PVY) is distributed worldwide and is one of the most damaging viruses in terms of yield reduction in the potato (Solanum tuberosum L.) crop with losses sometimes reaching 80%. To reduce its impact, there is great interest in obtaining varieties carrying the Ry adg gene that provides extreme resistance to this virus. This could be facilitated with SCAR (sequence characterized amplified region) RYSC3 by molecular marker-assisted selection (MAS). This study compared the effectiveness of the RYSC3 marker in the detection of the Ry adg gene vs. biological tests on populations of the Potato Breeding Program of the Instituto de Investigaciones Agropecuarias (INIA), Chile. Within the group of 71 progenitors, 30 plants had some kind of...
Tipo: Journal article
Palavras-chave: MAS; Extreme resistance.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300002

Inventory of Ammonia Emissions from Livestock Production in Los Lagos and Los Ríos Regions, Chile
Provedor de dados: 117
Autores: Martínez-Lagos,Josué; Salazar,Francisco; Alfaro,Marta; Misselbrook,Tom  H.
This paper presents the first inventory of ammonia emissions from livestock production in Los Lagos and Los Ríos Regions of Chile. The inventory was focused in this area because is where cattle production is concentrated. This study aimed to quantify the amount of N losses due to ammonia volatilization from livestock production in these regions of the country, and to provide its spatial representation identifying their main sources. Calculations have been carried out for 1997 and 2007, and also projections to 2017 and 2027 were obtained. Calculated emissions were 6097 and 6206 t NH3-N for 1997 and 2007, respectively. Major sources of NH3-N emissions were cattle accounting for more than 85%, followed by horses and pigs. Farm management practices as grazing,...
Tipo: Journal article
Palavras-chave: Ammonia; Inventory; Livestock production; Emissions.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100010

Influence of Arbuscular Mycorrhizal Fungi and Pseudomonas fluorescens at Different Superphosphate Levels on Linseed (Linum usitatissimum L.) Growth Response
Provedor de dados: 117
Autores: Neetu,Neetu; Aggarwal,Ashok; Tanwar,Anju; Alpa,Alpa.
The aim of this study was to investigate the influence of arbuscular mycorrhizal fungi (AMF) Glomus mosseae (T.H. Nicolson &amp;amp; Gerd.) Gerd. &amp;amp; Trappe and Acaulospora laevis (Gerd. &amp;amp; Trappe) on linseed (Linum usitatissimum L.) growth response with phosphate solubilizing bacteria Pseudomonas fluorescens; different doses of superphosphate were used: 20 kg ha4 (half recommended dose), 40 kg ha4 (recommended dose), and 80 kg ha4 (double recommended dose) in earthen pots filled with sterilized soil under greenhouse conditions. Among all the growth parameters, the following were the highest in the G. mosseae + P. fluorescens combination at the medium concentration (recommended superphosphate dose): plant height (78.74 ± 1.8 cm), fresh shoot...
Tipo: Journal article
Palavras-chave: AM fungi; P uptake; P activity.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200012

Effect of Californian Red Worm (Eisenia foetida) on the Nutrient Dynamics of a Mixture of Semicomposted Materials
Provedor de dados: 117
Autores: Castillo,Hugo; Hernández,Adriana; Dominguez,David; Ojeda,Damaris.
The efficiency of composting processes with and without the addition of Californian red worms (Eisenia foetida) was evaluated, using manure of dairy cows to generate organic fertilizer. Several parameters were assessed as physio-chemical indicators of maturity, such as temperature, pH, C/N ratio, phytotoxicity and macro and micronutrients at 25 and 54 ws (mature and stored products, respectively). A linear model was used in the statistical analysis, with four replicates that included as fixed effects, the composting systems and time. At 25 wk, both systems reduced the C/N ratio to values of 15.5 in vermicompost and 17.1 in semi-compost. The content of total N, N-NO3, Ca and some micronutrients also increased. K and Na concentrations were higher in the...
Tipo: Journal article
Palavras-chave: Fertilizer; Organic; Maturation; Stability.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300014

Long term salinity stress in relation to lipid peroxidation, super oxide dismutase activity and proline content of salt-sensitive and salt-tolerant wheat cultivars
Provedor de dados: 117
Autores: Borzouei,Azam; Kafi,Mohammad; Akbari-Ghogdi,Elahe; Mousavi-Shalmani,MirAhmad.
Salinity is a widespread root medium problem limiting productivity of cereal crops worldwide. The ability of plants to tolerate salt is determined by multiple biochemical pathways that facilitate retention and/or acquisition of water, protect chloroplast functions, and maintain ion homeostasis. Therefore, the ability of salt-sensitive ('Tajan') and salt-tolerant cultivar ('Bam') of Triticum aestivum L. to adapt to a saline environment were evaluated in a set of greenhouse experiments under salt stress during three growth stages (tillering, 50% anthesis, and 10 d after anthesis). Plants were irrigated by different saline waters with electrical conductivities of 1.3, 6, 8, 10, and 12 dS m-1, which were obtained by adding NaCl:CaCl2 in 10:1 molar ratio to...
Tipo: Journal article
Palavras-chave: Triticum aestivum; Salt stress; NaCl; Malondialdehyde.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400003

Evaluation of a Non-Destructive Impact Sensor to Determine On-Line Fruit Firmness
Provedor de dados: 117
Autores: Homer,Ian; García-Ramos,Francisco Javier; Ortiz-Cañavate,Jaime; Ruiz-Altisent,Margarita.
A non-destructive impact sensor to measure on-line fruit firmness was evaluated. This sensor is an adaptation of a static model used in the laboratory to measure fruit quality and was installed in an experimental fruit packing line with a commercial sizer chain. The firmness index is related to the acceleration-time curve supplied by an accelerometer attached to an impacting arm. The main objective of this study was to evaluate sensor performance and sources of variation. We made classification trials on three fruits: peaches (Prunus persica (L.) Batsch), apples (Malus domestica Borkh.), and pears (Pyrus communis L.), as well as working trials, such as placing the fruit, orientation, and others. The sensor works correctly at a speed of 7 fruits s-1 (0.63 m...
Tipo: Journal article
Palavras-chave: Packing line; Fruit quality; Peach; Low-energy impact; Sorting.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100007

Volatile Compounds in Honey Produced in the Central Valley of Ñuble Province, Chile
Provedor de dados: 117
Autores: Gianelli Barra,María Pía; Ponce-Díaz,María Cristina; Venegas-Gallegos,César.
Headspace solid-phase microextraction (SPME) with an 85 µm Carboxen polydimethylsiloxane (CAR/PDMS) fiber was used to extract volatile compounds, and a gas chromatograph equipped with a mass spectometry detector (GC-MS) was used to identify the volatile compounds in honeys. Thirty-four different volatile compounds from the headspace of honey produced in the central valley of Ñuble Province, Chile, were extracted with fiber coating CAR/PDMS. The identified compounds were: 10 alcohols, 9 acids, 6 ketones, 3 aldehydes, 2 furans, 2 terpenes and 2 lactones. Only four of the volatile compounds had never been reported before as honey compounds; these being: 1,3-propanodiol, 2-methyl butanoic acid, 3,4-dimethyl-3-hexen-2-one, and 6-methyl-5-octen-2-one. These four...
Tipo: Journal article
Palavras-chave: Solid phase microextraction; Volatile compounds; Honey.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100008

Evaluation of the ORYZA2000 Rice Growth Model under Nitrogen-Limited Conditions in an Irrigated Mediterranean Environment
Provedor de dados: 117
Autores: Artacho,Pamela; Meza,Francisco; Alcalde,José Antonio.
ORYZA2000 is a growth model for tropical lowland rice ( Oryza sativa L.) developed by the International Rice Research Institute and Wageningen University. This model has been evaluated extensively in a wide range of environments. However, reports examining japonica cultivars growing in temperate climates are scarce. In this study, ORYZA2000 was calibrated and evaluated using data from experiments carried out in the South-Central area of Chile. These experiments were performed on a japonica rice cultivar growing under an irrigated Mediterranean environment at various N rates. ORYZA2000 was then applied to explore potential yield and grain yield response to N fertilization under likely weather conditions in the major rice-producing area in Chile. ORYZA2000...
Tipo: Journal article
Palavras-chave: ORYZA2000 model; Irrigated rice; Nitrogen; Mediterranean environment; Chile.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100003

Productivity and Persistence of Yellow Serradela (Ornithopus compressus L.) and Biserrula (Biserrula pelecinus L.) in the Mediterranean Climate Region of Central Chile
Provedor de dados: 117
Autores: del Pozo,Alejandro; Ovalle,Carlos.
The production and sustainability of non-irrigated pastures in the Mediterranean climate region of central Chile is currently limited by the low diversity of valuable species and cultivars of annual forage legumes, able to persist in zones with highly variable annual rainfall, and low fertility or poorly drained soils. In this work, DM production, seed yield, hardseededness and pasture persistence were evaluated for cultivars of yellow serradella (Ornithopus compressus L.) and biserrula (Biserrula pelecinus L.), in field experiments conducted in the subhumid portion of the Mediterranean climate region of Chile. Burr medic (Medicago polymorpha L.) and sub clover (Trifolium subterraneum L.) were used as a reference plants. A remarkable DM production and seed...
Tipo: Journal article
Palavras-chave: Annual legumes; Hard-seed; Espinal; Plant density; Seed yield.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300006

Environmental Effects of Irrigation in Arid and Semi-Arid Regions
Provedor de dados: 117
Autores: Fernández Cirelli,Alicia; Arumí,José Luis; Rivera,Diego; Boochs,Peter  W.
This article reviews the state of the art with respect to the environmental effects of irrigated agriculture on water and soil quality in arid and semi-arid regions on a field scale. Information is scarce and fragmentary. Examples in selected areas of other arid and semi-arid regions in the world clearly show the importance of studying the environmental impact of irrigation practices on water and soil quality. Studies mainly refer to waterlogging and salinization. As regards agrochemicals, fertilizers have been taken into account through nitrate leaching. The impact of micropollutants such as pesticides and heavy metals on water and soil quality is studied mainly by modeling. Pharmaceutical compounds emerge as pollutants when wastewater is used for...
Tipo: Journal article
Palavras-chave: Irrigation; Water quality; Soil quality; Agrochemicals; Micropollutants.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000500004

Ovicidal effect of some insecticides on the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae)
Provedor de dados: 117
Autores: Mahmoudvand,Mohammad; Sheikhi Garjan,Aziz; Abbasipour,Habib.
The diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae), is a serious threat to Brassica vegetables in Iran, including Tehran province. The ovicidal effects of different classes of insecticides on P. xylostella were investigated, using three fixed doses (based on commercial formulations). At the lowest concentration (500 mg L-1), the mortality effect of hexaflumuron and pyridalyl was higher than the other insecticides examined. Fipronil, hexaflumuron and spinosad and pyridalyl, however, showed high toxic effects at the median dose (1000 mg L-1). On the other hand, at high concentration (2000 mg L-1), all insecticides except lufenuron and indoxacarb (EC formulation) caused more than 85% mortality. Overall, these findings indicate that...
Tipo: Journal article
Palavras-chave: Diamondback moth; Insecticides; Ovicidal effect.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200007

A Study of Dairy Farm Technical Efficiency Using Meta-Regression: An International Perspective
Provedor de dados: 117
This paper develops a meta-regression analysis to explain the variation of mean technical efficiency (PETP) measurements from a total of 65 frontier studies that report technical efficiency (ET) measurements at the dairy farm level in the literature published in English and Spanish. The analysis includes the effect of methodology on ET measurements, as well as the effect of the econometric procedure on the meta-regression estimates. Eight models were estimated, and two of these were selected: a fixed effects specification with dummy variables for the most significant studies without geographical effects (EFS), and a specification where the multiple observations are averaged and geographical effects included (OP). Based on model performance, the EFS option...
Tipo: Journal article
Palavras-chave: Meta-regression; Frontier models; Technical efficiency; Dairy farms.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200011

Chemical composition and antifungal activity of Piper auritum Kunth and Piper holtonii C. DC. against phytopathogenic fungi
Provedor de dados: 117
Autores: Pineda M,Rodrigo; Vizcaíno P,Samuel; García P,Carlos M; Gil G,Jesús H; Durango R,Diego L.
The growth of fungi during pre - and postharvest of fruits may cause spoilage and result in a reduction in quality and quantity. The aim of the present work was to investigate the efficacy of four extracts (n-hexane, dichlorometane, ethyl acetate, and methanol) and the essential oil of Piper auritum Kunth and P. holtonii C. DC. on the growth inhibition of three important postharvest pathogens of fruits (Colletotrichum acutatum, C. gloeosporioides, and Botryodiplodia theobromae). The in vitro antifungal activity was assayed following the poisoned food technique. The results showed that both n-hexane extract (HE) as essential oil (EO) displayed a relative good control against the three pathogens, being the originating materials of P. holtonii the most...
Tipo: Journal article
Palavras-chave: Piperaceae; Essential oil; Apiol; Colletotrichum; Botryodiplodia.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400008

Nutritional Aspects of Six Quinoa (Chenopodium quinoa Willd.) Ecotypes from three Geographical Areas of Chile
Provedor de dados: 117
Autores: Miranda,Margarita; Vega-Gálvez,Antonio; Quispe-Fuentes,Issis; Rodríguez,María José; Maureira,Héctor; Martínez,Enrique A.
This study explored the diversity of the quinoa crop in Chile from a nutritional perspective. Nutritional properties, minerals, vitamins, and saponin content were assessed in seeds of six Chilean quinoa (Chenopodium quinoa Willd.) ecotypes grown in three main production areas with distinctive climatic and edaphic conditions: Ancovinto and Cancosa in the North-Altiplano or High Plateau, Cáhuil and Faro in the central coastal area, and Regalona and Villarrica in the south of the country. There were significant differences (P &lt; 0.05) in all the nutritional properties of the quinoa seeds in all three areas. Quinoa of the Villarrica ecotype showed the highest protein content (16.10 g 100 g-1 DM) and the highest content of vitamins E and C (4.644 ± 0.240 and...
Tipo: Journal article
Palavras-chave: Quinoa; Vitamins; Minerals; Saponin content; Nutritional properties.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200002

Consumer Perception of Animal Welfare and Livestock Production in the Araucania Region , Chile
Provedor de dados: 117
Autores: Schnettler M,Berta; Vidal M,Ricardo; Silva F,Roberto; Vallejos C,Lisette; Sepúlveda B,Néstor.
Given the importance of animal welfare (AW) in developed countries, a survey was carried out among 384 consumers in Temuco, Chile, to establish their knowledge and perceptions about animals handling during production, to detect preferences for meat produced under AW principles, their willingness to pay a higher price for this and to distinguish different consumer segments. Approximately 60% of people surveyed knew about livestock management practices, half of them considered that these practices had a negative effect on the animals, but only 32.1% have changed their meat consumption habits due to this. Seventy percent of the people surveyed had over 50% of knowledge about AW aspects. There is a strong preference and willingness to pay a higher price for...
Tipo: Journal article
Palavras-chave: Animal welfare; Market segmentation; Cluster analysis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100008

Characterization of Anatomical, Chemical, and Biodegradable Properties of Fibers from Corn, Wheat, and Rice Residues
Provedor de dados: 117
Autores: Garay M,Rose Marie; Rallo de la B,Mónica; Carmona C,René; Araya C,Jaime.
Anatomical, chemical, and biodegradation properties of fibers from wheat (Triticum aestivum L.), rice (Oryza sativa L.), and corn (Zea mays L.) plant residues and from rice hull were characterized to generate scientific and technical knowledge to support decision making regarding their use. The anatomical and chemical properties were determined following standard procedures. The degree of biodeterioration was analyzed from growth of white rot fungus Pleurotus ostreatus (Jaq.) Quél. in 30 d under favorable conditions. Afterwards, weight loss was evaluated for each residue. Three replicates were used, plus a control of radiata pine (Pinus radiata D. Don) woodchips. The greatest proportion of a-cellulose was found in residues of rice plants (45.1%), with a...
Tipo: Journal article
Palavras-chave: Agriculture fibers; Biodeterioration; Crop residues; White rot.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300014

Alterations of the Antioxidant Enzyme Activities are not General Characteristics of the Colonization Process by Arbuscular Mycorrhizal Fungi
Provedor de dados: 117
Autores: Rodríguez,Yakelin; Vierheilig,Horst; Mazorra,Luis M.
Antioxidant system is involved in arbuscular mycorrhizal symbiosis, but its role during the colonization process is still poorly understood. To gain new insights into the role of antioxidant system during root colonization by arbuscular mycorrhizal fungi, the activities of key antioxidant enzymes were evaluated in tomato (Solanum lycopersicum L.) roots inoculated with six strains of different genera and species: two Glomus mosseae, Glomus cubense, Glomus intraradices, Glomus sp. and Acaulospora scrobiculata. Glomus cubense and A. scrobiculata strains reached the highest infectivity levels with maximum values of colonization frequency and intensity of 29-10.88% and 18-9.20%, respectively; G. mosseae strains showed an intermediate infectivity, both with 15%...
Tipo: Journal article
Palavras-chave: Peroxidases; Polyphenol oxidases; Superoxide dismutase; Colonization intensity; Solanum lycopersicum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300016

House Fly (Musca domestica L.) (Diptera Muscidae) Development in Different Types of Manure
Provedor de dados: 117
Autores: Larraín S,Patricia; Salas F,Claudio.
Animal production units with different management systems can be found along the Huasco Valley, Region of Atacama, Chile. These constitute sources of house flies (Musca domestica L.) and other vector fly species that cause damage to animals and nuisance problems in urban areas. In order to asses the importance of fly breeding sources, an experiment was carried out under laboratory conditions to evaluate different types of animal manure and composted swine manure. Time of larval development, larva mortality, pupa size, and weight and time of development to the adult stage were assessed. Results show that swine, poultry and calf manure produced a significantly higher number of adult flies, shorter life cycles and larger and heavier pupae. Cow, dog, goat and...
Tipo: Journal article
Palavras-chave: Flies; Animal manures; Compost.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200009

Antifeeding and Insecticide Properties of Aqueous and Ethanolic Fruit Extracts from Melia azedarach L.on the Elm Leaf Beetle Xanthogaleruca luteola Müller
Provedor de dados: 117
Autores: Chiffelle,Italo; Huerta,Amanda; Azúa,Fernando; Puga,Karla; Araya,Jaime E.
Xanthogaleruca luteola Müller (Coleoptera: Chrysomelidae), a defoliator of Ulmus species currently present in several regions of central Chile, causes severe damage to trees, mainly in park areas, street tree-lines and gardens. The antifeeding and insecticidal activities of extracts from immature fruit of Melia azedarach L. (Meliaceae) were determined on adults of X. luteola in laboratory bioassays. Several concentrations of the extracts obtained with water and ethanol were used and their effectiveness and LC50 were determined. The antifeeding action of the water extracts caused 100% deterrence over concentrations of 3.6% w/v. Both extracts were effective insecticides against adults, causing 86% mortality (2.4% w/v), with a better performance of the...
Tipo: Journal article
Palavras-chave: Botanical insecticides; Ethanol extract; Water extract.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200006

Biological Activity in a Degraded Alfisol Amended with Sewage Sludge and Cropped with Yellow Serradela (Ornithopus compressus L.)
Provedor de dados: 117
Autores: Celis H,José; Machuca H,Angela; Sandoval E,Marco; Morales C,Patricia.
There are few studies about the impact of sewage sludge on the biological properties in Alfisols of the Chilean Coastal Range drylands. Hence, the objective of this study was to evaluate its effect on the microbial respiration and enzymatic activities of a degraded Alfisol located in the Bío Bío Region (Chile) that was cropped with yellow serradela (Ornithopus compressus L.). Sludge was added to the soil at rates of 15, 30, and 60 t ha-1; he following treatments were defined: L15-P = 15 t ha-1 sludge + O. compressus; L30-P = 30 t ha-1 sludge + O. compressus; L60-P = 60 t ha-1 sludge + O. compressus; L15 = 15 t ha-1 sludge; L30 = 30 t ha-1 sludge; L60 = 60 t ha-1 sludge; CP = non-amended soil, cropped; and C = non-amended soil, no crop. Soil microorganism...
Tipo: Journal article
Palavras-chave: Biosolids; Respiration; Enzymatic activity; Degraded soils; Remediation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000100020

Effect of Ethylene Inhibitors on Quality Attributes of Apricot cv. Modesto and Patterson during Storage
Provedor de dados: 117
Autores: Valdés,Héctor; Pizarro,Melissa; Campos-Vargas,Reinaldo; Infante,Rodrigo; G. Defilippi,Bruno.
Apricot (Prunus armeniaca L.) fruit are highly susceptible to flesh softening, loss of flavor and fruit decay, particularly during postharvest storage. Most of these quality changes observed during fruit ripening are under ethylene regulation. We performed a study with the objective of determining the effect of 1-methylcyclopropene (1-MCP) and aminoethoxyvinylglycine (AVG) applications on quality attributes of Modesto and Patterson apricot cultivars. 1-MCP was applied at a rate of 1000 and 10 000 nL L-1 of SmartFresh™, and AVG at a rate 100 and 1000 mg L-1 of Retain®. Quality evaluations were performed after 20 and 30 days of cold storage and after a shelf-life period of 3-4 days at 20 °C. In general, both ethylene inhibitors were effective in reducing the...
Tipo: Journal article
Palavras-chave: Ripening; Quality; 1-methylcyclopropene; Aminoethoxyvinylglycine; Aroma.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200002

Lleuque-INIA, New High Yield Spring Durum Wheat Variety for Chile
Provedor de dados: 117
Autores: Matus,Iván; Madariaga,Ricardo; Alfaro,Christian; Jobet,Claudio.
The Lleuque-INIA spring durum wheat variety (Triticum turgidum var. durum L.) originated from a cross carried out by the Instituto de Investigaciones Agropecuarias (INIA), National Wheat Program, in the Centro Regional de Investigación La Platina, Santiago, Chile, in 1993. This variety has an upright growth habit in the seedling stage; the adult plant is of medium height and varies between 80 and 90 cm. The spike is medium-sized, white, and exhibits long whitish awns along its full length. The grain is large-sized, elongated, golden yellow, and vitreous. The variety was sown in mid-August in the Santa Rosa Experimental Station (36°31’ S; 71°54’ W), Chillán, head emergence occurred between 89 and 91 d after sowing, and was 6 to 8 d later than ‘Llareta-INIA’...
Tipo: Journal article
Palavras-chave: Durum wheat; Lleuque-INIA.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200020

Relative Aerial Biomass Yield of Intercroped Alfalfa with Winter Forage Cereals
Provedor de dados: 117
Autores: Pereyra,Telmo; Pagliaricci,Héctor; Ohanian,Alfredo.
In the tropical regions of the world, intercropping is mostly associated with food grain production, whereas it is receiving increased attention in temperate regions as a means of efficient forage production. The aim of this work was to determine the relative yield of aerial biomass in alfalfa or lucerne (Medicago sativa L.) and winter forage cereals intercrops. These were done in eight systems resulting from the combination of species sown at different dates. The biomass was measured in three situations: alfalfa and cereal sole-crop and alfalfa-cereal intercrops, the relative biomass yields were calculated by the relative yield index (RYI). The field experiment was conducted as a bifactorial array in a randomized complete block design of two replicates....
Tipo: Journal article
Palavras-chave: Intercrops; Lucerne; Winter forage cereals; Relative aerial biomass yield.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300005

Laboratory Trials of Metarhizium anisopliae var. acridum (Green Muscle®) Against the Saxaul Locust, Dericorys albidula Serville (Orthoptera: Dericorythidae)
Provedor de dados: 117
Autores: Valizadeh,Heydar; Abbasipour,Habib; Mahmoudvand,Mohammad; Askary,Hassan; Reza Moniri,Vahid.
The saxaul locust, Dericorys albidula Serville (Orthoptera: Dericorythidae) is a major pest of saxaul plants in Qom province of Iran. During 2005-2006, different nymphal instars of bands of D. albidula were treated by aerial spraying of Metarhizium anisopliae var. acridum (Green Muscle®). The gasoline formulation of M. anisopliae var. acridum isolate IMI 330189 was applied in different conidial concentrations (10(6), 10(7), 10(8), 10(9), 10(10) and 10(13) spores mL-1) that were prepared in sterile distilled gasoline. Results showed that various concentrations significantly affected the 2nd, 3rd, 4th and 5th nymphal instars of D. albidula compared to control. In addition, there were no differences in the effects of the different concentrations in 2005, but...
Tipo: Journal article
Palavras-chave: Saxaul plants; Fungal insecticide; Nymphal instars; Gasoline formulation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400008

Life Table Parameters and Consumption Rate of Cydnodromus picanus Ragusa, Amblyseius graminis Chant, and Galendromus occidentalis (Nesbitt) on Avocado Red Mite Oligonychus yothersi (McGregor) (Acari: Phytoseiidae, Tetranychidae)
Provedor de dados: 117
Autores: Rioja S,Tommy; Vargas M,Robinson.
The avocado red mite Oligonychus yothersi (McGregor) is the major leaf pest in Chile’s avocado orchards. Itaffects leaf physiology and makes it necessary to seek new natural enemies to interact with low population densities of O. yothersi. The potentiality of three predator mites: Cydnodromus picanus Ragusa, Amblyseius graminis Chant, and Galendromus occidentalis (Nesbitt) was evaluated under laboratory conditions (27 ± 1.93ºC, 87 ± 3.61% H.R. and 16:8 (L:D) photoperiod) on avocado leaf disks Persea americana Mill. var. Hass (Ø = 5 cm) by separately feeding eggs, immature, and adult females of O. yothersi, and registering postembryonic development, consumption, as well as life table parameters. The postembryonic development of C. picanus was significantly...
Tipo: Journal article
Palavras-chave: Postembryonic development; Predation; Pollen; Biological control.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200005

Nitrogen, Phosphorus and Potassium Losses in a Grazing System with Different Stocking Rates in a Volcanic Soil
Provedor de dados: 117
Autores: Alfaro,Marta; Salazar,Francisco; Iraira,Sergio; Teuber,Nolberto; Villarroel,Dagoberto; Ramírez,Luis.
In Chile there is little information on nutrient losses in livestock systems. The experiment was carried out between 2004 and 2006. Two stocking rates (3.5 and 5.0 steers ha-1) were tested under rotational grazing with Black and White Friesian steers on a permanent pasture (67.5 kg N and 40 kg P ha-1 yr-1). To quantify surface runoff losses (N, P, K), three surface lysimeters (5 x 5 m) per treatment were established. N and K leaching losses were estimated with ceramic cups. Runoff and leachate samples were individually analyzed for available and total N, reactive (RP) and total P, and K. Dissolved organic N (DON) and organic P (OP) were estimated as the difference between total and available forms. The stocking rate did not increase total N, P and K losses...
Tipo: Journal article
Palavras-chave: Eutrofication; Water quality; Grazing; Andisol; Beef production.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200004

Effect of Injecting Hydrogen Peroxide into Heavy Clay Loam Soil on Plant Water Status, NET CO2 Assimilation, Biomass, and Vascular Anatomy of Avocado Trees
Provedor de dados: 117
Autores: Gil M,Pilar M; Ferreyra E,Raúl; Barrera M,Cristián; Zúñiga E,Carlos; Gurovich R,Luis.
In Chile, avocado (Persea americana Mill.) orchards are often located in poorly drained, low-oxygen soils, situation which limits fruit production and quality. The objective of this study was to evaluate the effect of injecting soil with hydrogen peroxide (H2O2) as a source of molecular oxygen, on plant water status, net CO2 assimilation, biomass and anatomy of avocado trees set in clay loam soil with water content maintained at field capacity. Three-year-old ‘Hass’ avocado trees were planted outdoors in containers filled with heavy loam clay soil with moisture content sustained at field capacity. Plants were divided into two treatments, (a) H2O2 injected into the soil through subsurface drip irrigation and (b) soil with no H2O2 added (control). Stem and...
Tipo: Journal article
Palavras-chave: Stomatal closure; Net photosynthesis; Root histology; Oxygen injection; Root hypoxia; Subsurface drip irrigation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100012

Herbicidal Potential of Drechslera spp. Culture Filtrates Against Parthenium hysterophorus L.
Provedor de dados: 117
Autores: Javaid,Arshad; Javaid,Amna; Akbar,Muhammad.
Herbicidal activity of culture filtrates of four Drechslera spp., namely D. australiensis (Bugnic.) Subram. &amp;amp; B.L. Jain, D. biseptata (Sacc. &amp;amp; Roum.) M.J. Richardson &amp;amp; E.M. Fraser, D. hawaiiensis Bugnic. ex M.B. Ellis, and D. holmii (Luttr.) Subram. &amp;amp; P.C. Jain, prepared in malt extract broth was investigated against parthenium weed (Parthenium hysterophorus L.) in both laboratory bioassays and pots. In laboratory bioassays, the effect of original (100%) and diluted (50%) culture filtrates of the four Drechslera spp. was studied on parthenium germination and seedling growth in 90 mm diameter Petri plates. Original culture filtrate of all the four Drechslera species significantly reduced germination, shoot length, shoot fresh...
Tipo: Journal article
Palavras-chave: Fungal culture filtrates; Natural herbicides.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400020

Interrelationships between Grain Nitrogen Content and other Indicators of Nitrogen Accumulation and Utilization Efficiency in Wheat Plants
Provedor de dados: 117
Autores: Nikolic,Olivera; Zivanovic,Tomislav; Jelic,Miodrag; Djalovic,Ivica.
The topic of N wheat nutrition was prevalent during the last decades of the 20th century for many reasons such as energy crises, profitability of small grain production, and ecosystem protection and preservation. The objective of this study was to determine the interrelationships between wheat (Triticum aestivum L.) grain N content and other indicators of N nutrition efficiency to better understand the N nutrition process in wheat plants. The experiment included 30 wheat cultivars and experimental lines from Serbia. Plant samples of each genotype were taken at anthesis and maturity. The following parameters related to N accumulation and translocation within the wheat plant were calculated: N content (at anthesis, grain, straw, and total at maturity), N...
Tipo: Journal article
Palavras-chave: Interactions; Nitrogen nutrition; Path coefficients.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100018

Presence of a Phytoplasma Associated with Witches’-Broom Disease in Ugni molinae Turcz. and Gaultheria phillyreifolia (Pers.) Sleumer Determined by DAPI, PCR, and DNA Sequencing
Provedor de dados: 117
Autores: Arismendi S,Nolberto; Andrade S,Nancy; Riegel Sch,Ricardo; Carrillo Ll,Roberto.
Murta (Ugni molinae Turcz.) and common chaura (Gaultheria phillyreifolia (Pers.) Sleumer) are native species of Chile. Plants of both species have shown over-branching like witches' broom. The causal agents of these symptoms in many plants are phytoplasma. To verify the presence of these microorganisms, DAPI (4',6-diamidino-2-phenylindole) staining analysis and polymerase chain reaction (PCR) were performed in symptomatic and asymptomatic plants. Positive PCR samples were sequenced to identify the pathogens involved. In individuals of both species with witches’ broom symptoms, DAPI staining showed fluorescent bodies in the phloem tissues, but not in asymptomatic plants. Verification by nested-PCR, phytoplasmatic DNA was amplified from diseased murta and...
Tipo: Journal article
Palavras-chave: Native shrubs; Witches’ broom; Phytoplasma; Microscopic and molecular tools.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100003

Side Effects of Fungicides Used in Cucurbitaceous Crop on Trichogrammaatopovirilia Oatman &amp;amp; Platner (Hymenoptera: Trichogramatidae)
Provedor de dados: 117
Autores: Pratissoli,Dirceu; Milanez,André M.; Barbosa,Wagner F.; Celestino,Flávio N.; Andrade,Gilberto S.; Polanczyk,Ricardo A.
Trichogramma spp. (Hymenoptera: Trichogrammatidae) can control Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae). On the other hand, pesticides may reduce the efficiency of natural enemies. The objective was to evaluate the side-effects of fungicides used in the production of cucurbitaceous crops on Trichogramma atopovirilia Oatman &amp;amp; Platner parasitizing D. hyalinata eggs. The fungicides used in bioassays were: azoxystrobin (0.08 g active ingredient [ai] L-1), chlorothalonil (2.00 g ai L-1), mancozeb (1.60 g ai L-1), tebuconazole (0.25 g ai L-1) and thiophanate-methyl (0.49 g ai L-1). Cardboards with 30 D. hyalinata eggs previously immersedin fungicide solutions and distilled water (control) were offered separately to 20 newly emerged T....
Tipo: Journal article
Palavras-chave: Cucurbit borer; Pesticides; Egg parasitoid; Selectivity.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200016

In vitro Propagation of Cedar (Cedrela odorata L.) from Juvenile Shoots
Provedor de dados: 117
Autores: García-Gonzáles,Rolando; Delgado,Miladys; González,Yailín; González,Aníbal; Garriga,Miguel; Caligari,Peter  D.S; Carrasco,Basilio; Quiroz,Karla.
Cedrela odorata L. is one of the most important timber species currently traded in the Caribbean and Central America; however, it has been intensively exploited. In vitro techniques and clonal propagation can help to develop new plantations and assist in establishing improvement programs for this species. The aim of this study was to develop a protocol to establish in vitro conditions and to micropropagate this species from nodal explants from juvenile cuttings taken from field trees. Disinfection of node explants with 5% propiconazole CE 25 during 3 min resulted in 100% explant disinfection and 60% morphogenic response on those established explants. Shoot development was optimized by cultivating in vitro node explants in Murashige and Skoog basal medium...
Tipo: Journal article
Palavras-chave: Organogenesis; In vitro propagation; In vitro rooting; Plant growth regulators.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300005

Bioactivity of Lantana camara L. essential oil against Callosobruchus maculatus (Fabricius)
Provedor de dados: 117
Autores: Zandi-Sohani,Nooshin; Hojjati,Mohammad; Carbonell-Barrachina,Ángel A.
Lantana camara L. is a widespread plant species mostly native to subtropical and tropical regions of the world. In this study, insecticidal and repellent activities of L. camara essential oil were evaluated against Callosobruchus maculatus (Fabricius) (Col: Bruchidae). Analysis of chemical composition by gas chromatography/mass spectrometry (GC/MS) showed high amounts of sesquiterpenes, mainly &amp;#945;-humelene (23.3%) and cis-caryophyllene (16.2%). The results showed that the essential oil of L. camara has strong repellent activity against adults of C. maculatus at all tested concentrations. After 2 and 4 h, 97.4 and 100% repellency was seen at highest concentrations of 0.4 &amp;#956;L cm-2, respectively. Moreover, the oil was found to be toxic to...
Tipo: Journal article
Palavras-chave: Fumigant; Insecticidal activity; Bean protection; Lantana camara.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400007

Effect of Harvest Time and L-Cysteine as an Antioxidant on Flesh Browning of Fresh-Cut Cherimoya (Annona cherimola Mill.)
Provedor de dados: 117
Autores: Campos-Vargas,Reinaldo; Defilippi,Bruno G; Romero Q,Paula; Valdés G,Héctor; Robledo M,Paula; Prieto E,Humberto.
Browning development is the most important factor limiting the quality of fresh-cut cherimoya (Annona cherimola Mill.). However, there is little information available about its causes and methods of control. The effectiveness of L-cysteine (0.125, 0.25 and 0.5%) in fresh-cut cherimoya harvested on two occasions (October and November) and stored for 6 and 12 days at 0 °C was studied. In order to understand the biological basis of browning, polyphenol oxidase (PPO) enzyme activity and total phenolic content in fresh-cut pieces were measured. Quality measurements and sensory analysis indicated that 0.5% L-cysteine was somewhat effective in reducing browning development, without affecting other quality attributes. In terms of physiological parameters, PPO...
Tipo: Journal article
Palavras-chave: Antioxidants; Polyphenol oxidase; Phenolics; Sensorial evaluation.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300001

Physical and Chemical Characterization of Melia azedarach L. Fruit and Leaf for Use as Botanical Insecticide
Provedor de dados: 117
Autores: Chiffelle G,Italo; Huerta F,Amanda; Lizana R,Diego.
A study was undertaken of the physical and chemical characteristics and insecticide properties of melia (Melia azedarach L.) (Meliaceae) fruit and leaves; melia has been introduced in Chile for ornamental purposes. The physical and chemical properties were evaluated in two stages of fruit and leaf maturity, i.e., green /mature, and mature/juvenile, respectively. Laboratory bioassays were carried out on Drosophila melanogaster Meigen (Diptera: Drosophilidae) as an insect model. The diameter of M. azedarach fruit was in the lower limit in relation to other studies. The flour obtained from green fruit had an average dry weight inferior to that of mature fruit. The average dry leaf weights were similar in both juvenile and mature states. The green fruits had...
Tipo: Journal article
Palavras-chave: Chinaberry tree; Meliaceae; Phenolic compounds.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100005

Effect of Compost Application on Some Properties of a Volcanic Soil from Central South Chile
Provedor de dados: 117
Autores: Valarini,Pedro José; Curaqueo,Gustavo; Seguel,Alex; Manzano,Karina; Rubio,Rosa; Cornejo,Pablo; Borie,Fernando.
Soil compost application is a common soil management practice used by small farmers of Central-South Chile that produces positive effects on soil properties and also promotes presence and activity of arbuscular mycorrhizal fungi (AMF). This fungi form symbiosis with plant roots improving plant nutrition, as well as producing glomalin, a glycoprotein that has been associated with soil aggregation stability. Therefore, the aim of this study was to evaluate, in an Ultisol from Central-South Chile, the effect of different doses of compost on some soil characteristics at the end of the third year of a crop sequence including wheat (Triticum aestivum L.), bean (Phaseolus vulgaris L.), and grassland (Lolium multiflorum Lam. associated with Trifolium repens L.)....
Tipo: Journal article
Palavras-chave: Compost; Glomalin; Soil aggregation; Ultisol.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000300015

Effect of Two Entomopathogenic Fungi in Controlling Aleurodicus cocois (Curtis, 1846) (Hemiptera: Aleyrodidae)
Provedor de dados: 117
Autores: Núñez del Prado,Elizabeth; Iannacone,José; Gómez,Hilda.
Aleurodicus cocois (Curtis, 1846), the coconut whitefly, is a very damaging pest in Peru, mainly in avocado trees (Persea americana Mill.). It has been determined that entomopathogenic fungi can infect and kill white flies and can be used as biological control agents. The object of this research was to determine if there is any synergic action of the entomopathogenic fungi Paecilomyces fumosoroseus (Wize) Brown &amp;amp; Smith 1957 and Verticillium lecanii (Zimmerman, 1892) Viégas 1939, in controlling A. cocois. Plastic sterile dishes were prepared where 5 mL 2% agar were used for each stage; leaves infested with A. cocois were placed upon these. Three different treatments were applied by sprinkling: P. fumosoroseus (P), V. lecanii (V) or the mixture of...
Tipo: Journal article
Palavras-chave: Biocontrol; Pest; White flies.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100003

Effect of feeding Acacia saligna (Labill.) H.L. Wendl. on goats stabled during late pregnancy and lactation
Provedor de dados: 117
Autores: Meneses R,Raul; Olivares V,Yohana; Martinoli S,Milenko; Flores P,Hugo.
Acacia saligna (Labill.) H.L. Wendl. forage is an alternative feed supply for goats during dry periods It was used as feed during pregnancy and lactation to evaluate production response and some blood parameters. Six animals in each group were fed with 0, 25, 50, 75, and 100% of acacia as alfalfa (Medicago sativa L.) hay replacement in a completely randomized design. Forage chemical analysis was done to calculate nutrient intake. Blood samples were analyzed for albumin, urea N, globulin, total protein, Ca, and P. Productive parameters were analyzed by ANOVA, Duncan, and regression analyses between acacia and dry matter (DM), crude protein (CP), metabolizable energy (ME), and milk production. Acacia consumption during pregnancy was 65.5% of control,...
Tipo: Journal article
Palavras-chave: Acacia saligna; Pregnancy; Lactation; Milk production; Goats; Albumins.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400014

Allelopathic Activity of Crop Residue Incorporation Alone or Mixed Against Rice and its Associated Grass Weed Jungle Rice (Echinochloa colona [L.] Link)
Provedor de dados: 117
Autores: Khaliq,Abdul; Matloob,Amar; Ata Cheema,Zahid; Farooq,Muhammad.
Weed suppression is one of the several benefits achieved by soil incorporation of crop residues and such suppression is believed to be allelopathic in nature. The allelopathic potential of different crop residues: viz. sorghum (Sorghum bicolor [L.] Moench), sunflower (Helianthus annuus L.), brassica (Brassica campestris L.) was evaluated in rice (Oryza sativa L.) and jungle rice (Echinochloa colona [L.] Link). Chopped crop residues were soil-incorporated alone and mixed at 6 g kg-1 soil (12 t ha-1) and compared with a control without residues. Soil incorporation of residues substantially delayed germination of jungle rice. The time to start germination, time to 50% emergence, mean emergence time, emergence index, and final germination percentage were all...
Tipo: Journal article
Palavras-chave: Residues; Allelopathy; Sorghum; Sunflower; Brassica; Weed control.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300012

Paclobutrazol for Height Control of Petunias
Provedor de dados: 117
Autores: Francescangeli,Nora; Zagabria,Ana.
The effects of paclobutrazol on the height of Petunia × hybrida hort. ex E. Vilm. were studied. An experiment on 'Bravo F1' was performed at the National Institute for Agricultural Technology (INTA), San Pedro Agricultural Experimental Station (33º4’ S, 59º4’ W), Buenos Aires Province, Argentina, in the spring of 2006. Treatments consisted of three colours of flower (white, red and blue), four concentrations of paclobutrazol by irrigation (0, 5, 10 and 15 mg L-1 and three application times (at 10-12, 18-20 and 26-28 leaves). Height at 45 d after transplanting (dat), days to appearance, opening and fall of the first flower and number of flowers at 21 and 45 dat were registered. Differences between control plants due to flower colour were detected, and would...
Tipo: Journal article
Palavras-chave: Plant growth regulator; Plant architecture; Flower colour; Application time.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300012

Field Testing of Tomato Chilling Tolerance under Varying Light and Temperature Conditions
Provedor de dados: 117
Autores: Elizondo,Rafael; Oyanedel,Eduardo.
Chilling tolerance is a desirable trait in commercial tomato varieties, in order to extend the growing season and geographic range. Two Nearly Isogenic Lines (NILs) with introgressions in chromosome 2 and 3 of Solanum habrochaites S. Knapp &amp;amp; D.M. Spooner, a cold-resistant wild tomato, were evaluated in the field. Four plantings were established between 21 August and 2 October 2006 (day 232 and 274). Throughout the experiment the heat sum was interpreted using air temperature to calculate growing degree days (base 12 °C) and chilling hours (below 12 °C), with the daily light integral calculated as global solar radiation. The relative post-transplant growth rate, fruit set and yield, were evaluated over two successive 10-d periods. Chilling tolerance...
Tipo: Journal article
Palavras-chave: Linkage drag; NILs.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400004

Evaluation of Top-Cross Popcorn Hybrids Using Mixed Linear Model Methodology
Provedor de dados: 117
Autores: Arnhold,Emmanuel; Mora,Freddy; G. Silva,Ricardo; I.V. Good-God,Pedro; Rodovalho,Marcos A.
The market for popcorn (Zea mays L.) has been continuously growing in Brazil fact has required the development of cultivars adapted to local environmental conditions. For this reason, the analytical objectives of this study were to evaluate top-cross popcorn hybrids in relation to popping expansion and grain yield in three different eco-geographic regions of Brazil, in order to estimate variance components using Restricted Maximum Likelihood (REML) and predict breeding values using Best Linear Unbiased Prediction (BLUP). Genetic evaluation considered a linear model with heterogeneous residual (environmental) variances. The Restricted Likelihood Ratio Test (RLRT) evidenced significant differences (p &lt; 0.01) for the genotypic effect. Grain yield showed a...
Tipo: Journal article
Palavras-chave: Popping expansion; REML; BLUP; Improvement.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100006

Isolation and Selection of Epiphytic Yeast for Biocontrol of Botrytis cinerea Pers. on Table Grapes
Provedor de dados: 117
Autores: Vargas,Marisol; Garrido,Felipe; Zapata,Nelson; Tapia,Maritza.
Botrytis cinerea Pers., the causal agent of gray mold, infects more than 200 plant species. This pathogen has traditionally been controlled by fungicides. However, with the increasing demand for pesticide-free foods new control strategies are needed. The objective of this study was to isolate and select grapevine (Vitis vinifera L.) epiphytic yeasts for the biocontrol of B. cinerea in table grapes. Of the total isolated yeasts (n = 256), 32 exhibited mycelial growth inhibition in dual cultures with a halo &gt; 4 mm, and eight of these isolates inhibited &gt; 90% of conidial germination. When evaluating increasing concentrations on conidial germination inhibition, a dose-dependent response was observed with EC90 values from 0.45 x 10(5) to 0.22 x 10(8)...
Tipo: Journal article
Palavras-chave: Gray mold; Antagonistic yeast; Biocontrol agents; Vitis vinifera.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300005

Control of San Jose Scale Nymphs, Diaspidiotus perniciosus (Comstock), on Almond and Apple Orchards with Pyriproxyfen, Phenoxycarb, Chlorpyrifos, and Mineral Oil
Provedor de dados: 117
Autores: Sazo,Luis; Araya,Jaime E; Esparza,Sergio.
The effect of pyriproxyfen, phenoxycarb, chlorpyrifos, and mineral oil in the control of first generation nymphs of the San Jose scale (SJC), Diaspidiotus perniciosus (Comstock), in almond, Prunusdulcis (Mill.) D.A. Webb, and apple, Malusdomestica Borkh. orchards was studied in the 2001-2002 season in central Chile. One and two sprays of pyriproxyfen 0.07% and phenoxycarb 0.05% were applied, the first at the beginning of the appearance of nymphs in early spring (biofix), and the other 15 days later, and were compared with one spray of chlorpyrifos 0.08% applied at the biofix. Also, one and two sprays of mineral oil 1% were evaluated, the first applied 7 days after the biofix, and the second 15 days after the first spray. Evaluations were done in the...
Tipo: Journal article
Palavras-chave: Mineral oil; Phenoxycarb; Pyriproxyfen; San Jose scale.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000300008

Assessing the Transferability of Transpiration-use Efficiency Models of Biomass Production
Provedor de dados: 117
Autores: Kremer,Cristián; Stöckle,Claudio.
Transpiration-use efficiency (w), defined as the ratio of biomass produced per unit water transpired, has been used to evaluate crop performance under limited water supply. However, the lack of consistency of w values through different environmental conditions has not allowed, using it as a transferable parameter. Thus, simple approaches have been developed, including: 1) w = kDa Da¹ and; 2) w = kEto ETo-¹ where kDa and kETo are crop-dependent parameters, with the underlying concept that normalization by Da or ET0 would accounts for the effects of climate variations on w, while these parameters would be reasonably constant across diverse environments. The objective of this study was to assess the transferability of kDa and kET&amp;#094;0 for wheat...
Tipo: Journal article
Palavras-chave: Transpiration-use efficiency; Models of biomass production.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100002

Endogenous Quantification of Abscisic Acid and Indole-3-Acetic Acid in Somatic and Zigotic Embryos of Nothofagus alpina (Poepp. &amp;amp; Endl.) Oerst
Provedor de dados: 117
Autores: Cartes Riquelme,Pricila; Ríos Leal,Darcy; Sáez Carrillo,Kátia; Uribe Moraga,Matilde; Valenzuela Aguilar,Sofía; Joseph Bolus,Stephen; Sánchez Olate,Manuel.
Abscisic acid (ABA) and indole-3-acetic acid (IAA) participate in the propagation of plants by somatic embryogenesis, causing polar structural differentiation of the embryo. The goal of the assay was to compare endogenous levels of ABA and IAA between somatic embryos (SE) and zygotic embryos (ZE) of Nothofagus alpina (Poepp. &amp;amp; Endl.) Oerst. In this study, a somatic embryo maturation assay involving the addition of varying concentrations of exogenous ABA was performed on cotyledonary-stage of N. alpina. Furthermore, the endogenous levels of ABA and IAA were quantified in the immature ZE, the mature ZE, and the embryonic axis of a mature embryo of N. alpina. The current study utilized high performance liquid chromatography (HPLC) for quantification....
Tipo: Journal article
Palavras-chave: Somatic embryogenesis; Maturation; Germination; HPLC.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400007

Impact of Nursery Seeding Density, Nitrogen, and Seedling Age on Yield and Yield Attributes of Fine Rice
Provedor de dados: 117
Autores: Sarwar,Naeem; Maqsood,Muhammad; Aftab Wajid,Syed; Anwar-ul-Haq,Muhammad.
Producing vigorous seedlings and transplanting them at the appropriate age are the most important factors for obtaining high yield in rice (Oryza sativa L.) paddy production. The impact of seeding densities, N, and seedling age was evaluated in this experiment after transplanting 10, 20, 30 and 40-d old seedlings raised by using different seeding rates (high and low) and N conditions (with and without) in the 2008 and 2009 rice growing seasons. The study revealed that 10-d-old nursery seedlings, irrespective of seeding densities and fertilizer application, showed higher yields and yield attributes (productive tillers, plant height, 1000-grain weight, and straw yield), while at later stages significant interaction was observed with nursery management....
Tipo: Journal article
Palavras-chave: Rice; Nursery; Seedling age; Yield.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300001