Consulta: creatorFacets:"AGOSTINETTO,D."
Registros recuperados: 35
Data/hora: 09/06/2024 04:34:06

Fitness Cost and Competitive Ability to Different Ploidy Levels in Ryegrass Genotypes
Provedor de dados: Planta Daninha
Autores: SCHMITZ,M.F.; CECHIN,J.; HENCKES,J.R.; PIASECKI,C.; AGOSTINETTO,D.; VARGAS,L.
ABSTRACT: The intergenotypic competition of tetraploid ryegrass with natural diploid population may be a tool to reduce the frequency of resistant individuals in an area. This study aimed to identify and compare the phenological development, fitness cost, and competitive ability between diploid and tetraploid ryegrass genotypes. Genotypes were grown in pots, and the morphological variables of genotype growth were assessed every 15 days up to 120 days after emergence to evaluate the fitness cost. Phenological development and seed yield components were measured in a single time together with the fitness cost. Competitive ability was determined in a replacement-series experiment with proportions of tetraploid and diploid ryegrass, in which the number of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lolium multiflorum; Competition; Diploid; Tetraploid; Integrated weed management.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100189

Longevity of Horseweed Seed Bank Depending on the Burial Depth
Provedor de dados: Planta Daninha
Autores: VARGAS,A.A.M.; AGOSTINETTO,D.; ZANDONÁ,R.R.; FRAGA,D.S.; AVILA NETO,R.C.
ABSTRACT: Horseweed (Conyza spp.) is considered as one of the major weeds occurring in the agricultural areas of South America, especially in Brazil. This species stands out from the other weeds due to characteristics such as large seed production, continued seed production, dispersion over long distances and resistance to 5-enolpyruvoylshikimate 3-phosphate (EPSP) and acetolactate synthase (ALS) inhibiting herbicides, features that increase their management. Therefore, this study aimed at determining the physiological quality and longevity of horseweed seeds over 12 months. The experiment was established under field conditions, using a randomized block design with four replications. Fifty horseweed seeds were distributed into 50 g of dry soil, placed in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conyza spp.; Survival; Dormancy; Germination; Viability.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100249

Photosynthetic Performance of Glyphosate Resistant and Glyphosate Susceptible Hairy Fleabane under Light Intensity
Provedor de dados: Planta Daninha
Autores: SILVA,D.R.O.; VARGAS,L.; AGOSTINETTO,D.; SANTOS,F.M.
ABSTRACT: Herbicide resistance can confer lower competitive abilities; however scarse information is available about the photosynthetic performance between glyphosate-resistant and -susceptible hairy fleabane biotypes coming from areas with similar weed management history. Thus, the goal was to evaluate the photosynthetic performance under different light intensities between glyphosate-resistant and -susceptible hairy fleabane biotypes, from RR soybean fields with a similar weed management history. The tested factors were glyphosate resistant and susceptible biotypes and 12 levels of photosynthetic photon flux density. Plants were cultivated in plastic cups, and at the stage of 10-12 leaves they were subjected to treatments with artificial lighting...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conyza bonariensis; Ecological adaptability; Photosynthetic photon flux; Carbon assimilation rate; Gas exchange; Light response curve.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100285

Response of Soybean Cultivars in Rotation with Irrigated Rice Crops Cultivated in Clearfield® System
Provedor de dados: Planta Daninha
Autores: AGOSTINETTO,D.; FRAGA,D.S.; VARGAS,L.; OLIVEIRA,A.C.B.; ANDRES,A.; VILLELA,F.A.
ABSTRACT: Soybean crop rotation with irrigated rice is an alternative for the management of weedy rice (Oryza sativa) resistant to herbicides from the imidazolinone chemical group. This work had the purpose to evaluate the phytotoxicity of soybean crops containing the technologies Cultivance® (CV) and tolerance to sulphonylurea and Roundup Ready® (RR), deriving from increasing doses of the imazapyr and imazapic herbicide mixture, applied in the irrigated rice crop management. Thus, the experiment was performed on field, where treatments consisted in three soybean cultivars (BRS382CV, CD249STS and NA5909RR) and five doses of the imazapyr and imazapic herbicides mixture (0, 49, 98, 196 and 392 g a.i. ha-1). The evaluated variables were phytotoxicity, yield...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Glycine max; Cultivance®.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100250

Morphological and Biochemical Alterations of Paddy Rice in Response to Stress Caused by Herbicides and Total Plant Submersion
Provedor de dados: Planta Daninha
Autores: MARCHEZAN,M.G.; AVILA,L.A.; AGOSTINETTO,D.; SCHAEDLER,C.E.; LANGARO,A.C.; OLIVEIRA,C.; ZIMMER,M.; SCHREIBER,F.
ABSTRACT Herbicide selectivity in paddy rice varies in several aspects, among which are the environmental conditions. The aim of the study was to evaluate the effect of herbicide application and total plant submersion on morphological and biochemical changes in paddy rice. Total chlorophyll and carotenoids, catalase activity, ascorbate peroxidase and superoxide dismutase, total phenolic content, lipid peroxidation and hydrogen peroxide levels were assessed. Leaf samples were collected 24 hours and 7 days after the application of water regimes. The results observed in the first experiment show that cultivars Puitá INTA CL, IRGA 417 and IRGA 422 CL are more tolerant to total submersion. The most sensitive cultivars are IRGA 424, BRS Querência, EPAGRI 108 and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oxidative stress; Hypoxia; Oryza sativa; Herbicide selectivity.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100201

Biochemical and Physiological Changes in Rice Plants Due to the Application of Herbicides1
Provedor de dados: Planta Daninha
Autores: LANGARO,A.C.; AGOSTINETTO,D.; OLIVEIRA,C.; SILVA,J.D.G.; BRUNO,M.S.
ABSTRACT The application of herbicides, even if selective, can cause biochemical and physiological changes, resulting in oxidative stress. This stress comes from the accumulation of reactive oxygen species produced due to exposure to the herbicide. However, plants have developed defense strategies, which can be enzymatic or non-enzymatic. The objective of this study was to evaluate the morphological and metabolic changes such as photosynthetic parameters, oxidative damage and antioxidant enzyme activity of rice plants after applying herbicides. For this, a study was conducted in a greenhouse and laboratory and the treatments consisted of application of imazapic + imazapyr, quinclorac, bentazon, cyhalofop-butyl, penoxsulan, bispyribac-sodium and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Oxidative stress; Lipid peroxidation; Selectivity.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000200277

Glyphosate Applied at the Early Reproductive Stage Impairs Seed Production of Glyphosate-Resistant Hairy Fleabane
Provedor de dados: Planta Daninha
Autores: PIASECKI,C.; MAZON,A.S.; MONGE,A.; CAVALCANTE,J.A.; AGOSTINETTO,D.; VARGAS,L.
ABSTRACT: Glyphosate-resistant hairy fleabane [Conyza bonariensis (L.) Cronq.] is one of the most important weeds in the world. Among the factors that make this weed species widely distributed in the most diverse environments is the high seed production capacity and dispersal. Hairy fleabane plants not controlled by herbicide application regrowth and overcome crop canopy, use environmental resources, interfere with crops, and complete their life cycle by producing thousands of seeds and replenishing the seed bank. Management strategies that reduce production and viability of hairy fleabane seeds can be adopted within the integrated management to reduce the seed bank and prevent further infestations. In this way, experiments were carried out in a greenhouse...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conyza bonariensis; Resistance; Integrated weed management; Prevention; Soil seed bank.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100198

Rapid Detection of Horseweed and Black Picker Sensitivity Levels to Saflufenacil
Provedor de dados: Planta Daninha
Autores: VARGAS,L.; HENCKES,J.R.; GAVA,F.; AGOSTINETTO,D.; CARVALHO,I.R.; RAMOS,R.; RODRIGUES,R.
ABSTRACT: Resistance to herbicides is one of the main factors responsible for weed control failures. Once uncontrolled and stressed, resistant weeds demand a new application of herbicides from different modes of action, which results in higher monetary costs and environmental impact. Knowledge of weed sensitivity levels to herbicides before making decisions for their management in the field is paramount to increasing the efficiency of integrated weed management. Thus, methods that allow the rapid determination of sensitivity levels can help to the correct recommendation before the application, and thus, favor the greater technical, economic and environmental efficiency of weed management. The objective of this work was to validate a rapid method to detect...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Integrated weed management; Resistance; Control; Efficiency.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100222

Changes in the Metabolism of Soybean Plants Submitted to Herbicide Application in Different Weed Management Systems
Provedor de dados: Planta Daninha
Autores: FRAGA,D.S.; AGOSTINETTO,D.; RUCHEL,Q.; LANGARO,A. C.; OLIVEIRA,C.
ABSTRACT: Technologies that advocate the use of herbicide-resistant crops are alternatives to weed control, but they may cause oxidative stress and change secondary metabolism of plants. Therefore, this study aimed to evaluate changes in the secondary metabolism of soybean plants which contained Cultivance® (CV), sulfonylurea-tolerant soybean (STS) and Roundup Ready® (RR) technologies submitted to the application of the mixture of herbicides imazapyr and imazapic in “plant-apply” and “apply-plant” management systems. Two field experiments, in which soybean cultivars were submitted to increasing doses of the mixture of herbicides imazapyr and imazapic, were performed. Aerial parts of plants were collected 10 days after crop emergence and stored at -83oC,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Oxidative stress; Chemical control.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582020000100243

METABOLIC ACTIVITY OF WHEAT AND RYEGRASS PLANTS IN COMPETITION
Provedor de dados: Planta Daninha
Autores: AGOSTINETTO,D.; TAROUCO,C.P.; NOHATTO,M.A.; OLIVEIRA,C.; FRAGA,D.S.
ABSTRACT Ryegrass is an annual cycle Poacea, often considered as a weed in wheat crops. The goal of this study was to analyze oxidative stress and enzyme activity of wheat and ryegrass cultures in response to stress caused by the competition between crop and weed, in two development stages. The experiment was conducted in completely randomized design, with eight replications, in replacement series, with a population of 64 plants per pot. Treatments consisted of proportions of ryegrass and wheat plants arranged in replacement series. The tested proportions were: 100/0 (pure wheat stand), 75/25, 50/50, 25/75 and 0/100% (pure ryegrass stand). The evaluated variables were: hydrogen peroxide (H2O2) content, thiobarbituric acid-reactive species (TBARS),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Triticum aestivum; Lolium multiflorum; Stress; Competitiveness.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100233

Resistence of Radish Biotypes to Iodosulfuron and Alternative Control
Provedor de dados: Planta Daninha
Autores: CECHIN,J.; VARGAS,L.; AGOSTINETTO,D.; ZIMMER,V.; PERTILE,M.; GARCIA,J.R.
The repetitive use of iodosulfuron for the control of weeds in winter cereals in the south of Brazil has favored the emergence of resistant Raphanus sativus biotypes. The objective of this study was to evaluate: the response of Raphanus sativus biotypes susceptible and resistant to different dosages of iodosulfuron; the control of biotypes with alternative registered herbicides for the control of the species in crops of wheat, corn and soybean; and the existence of cross-resistance of the biotypes. Thus, four experiments were done in a greenhouse, with a completely randomized design and four replicates. The experimental units were composed of vases with a volumetric capacity of 0.75 L filled with substrate, containing a plant each. For the dose-response...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Raphanus sativus; Dose-response; Acetolactate synthase; Weed.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000100151

Criteria for Decision Making and Economic Threshold Level for Wild Radish in Wheat Crop
Provedor de dados: Planta Daninha
Autores: TAVARES,L.C.; LEMES,E.S.; RUCHEL,Q.; WESTENDORFF,N.R.; AGOSTINETTO,D.
ABSTRACT: Weed competition limits wheat yield by reducing the availability of essential resources for its growth and development. In this sense, this study aimed to estimate the economic threshold level (ETL) of wild radish (Raphanus raphanistrum) in competition with wheat cultivars. Treatments were arranged in a factorial scheme. The factor wheat cultivar consisted of early (BRS 328), medium (BRS 177), and late (BRS Umbu) cycles and the factor wild radish population ranged from 0 to 564 plants m-2 (10 populations) for the cultivar BRS 328, 0 to 472 plants m-2 for the cultivar BRS 177 (11 populations), and 0 to 724 plants m-2 for the cultivar BRS Umbu (10 populations). The early-cycle BRS 328 presented a higher competitive ability when compared to the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Triticum aestivum L.; Raphanus raphanistrum; Cultivars; Populations.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100204

Changes in Photosynthesis and Oxidative Stress in Wheat Plants Submmited to Herbicides Application
Provedor de dados: Planta Daninha
Autores: AGOSTINETTO,D.; PERBONI,L.T.; LANGARO,A.C.; GOMES,J.; FRAGA,D.S.; FRANCO,J.J.
The use of herbicides, even in tolerant crops, can cause stress evidenced by increase phytotoxicity affecting growth and development. The objectives of this study were to evaluate herbicides effect from different mechanisms of action in photosynthetic and oxidative stress parameters, as well visual phytotoxicity and wild radish control in wheat crop, cultivar Quartzo. Two trials were conducted where the first one evaluated the photosynthetic parameters on wheat plants in two seasons collection, following the application of herbicides bentazon, clodinafop, iodosulfuron, metribuzin, metsulfuron and 2,4-D; and the second one evaluated wild radish (Raphanus sativus) control, wheat phytotoxicity and yield due to bentazon, iodosulfuron, metribuzin, metsulfuron...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Triticum aestivum; Selectivity; ROS; Antioxidant enzymes.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000100001

Physiological and Molecular Responses in Rice, Weedy Rice and Barnyardgrass Exposed to Supra-Optimal Temperatures
Provedor de dados: Planta Daninha
Autores: OLIVEIRA,C.; AGOSTINETTO,D.; LANGARO,A.C.; GARCIA,J.R.; LAMEGO,F.P.
ABSTRACT: The global temperature to rise 0.3 to 4.8 oC to century. Supra-optimal temperatures can affect plants at different organizational levels, causing morphological, physiological, biochemical and gene expression alterations. Rice, weedy rice, and barnyardgrass may to response differently when subjected to supra-optimal temperatures. Thus, the aimed at determining the physiological response and expression of the genes APX2, HSP24.15 e HSP71.10 in rice, weedy rice, and barnyardgrass when in to supra-optimal temperatures. A greenhouse experiment was conducted in randomized complete desing with four repetitions, with a factorial combination of temperature x plantas, where: factor A consisted of two temperatures (25 oC and 40 oC); and factor B of three...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Echinochloa spp.; Photosynthesis; Oxidative stress; Gene expression.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100239

CHANGE IN PHYSIOLOGICAL FEATURES IN RYEGRASS BIOTYPES IN COMPETITION WITH SOYBEAN DUE RESISTANCE TO GLYPHOSATE
Provedor de dados: Planta Daninha
Autores: AGOSTINETTO,D.; OLIVEIRA,C.; LANGARO,A.C.; NOHATTO,M.A.; MANICA-BERTO,R.
ABSTRACT Herbicide resistance can cause biochemical, physiological, morphological and phenological changes in weeds, altering their competitive ability against crops. The aim of the study was to assess physiological changes and cellular damage in susceptible and resistant biotypes of ryegrass and soybeans under competition. Three experiments were conducted in a greenhouse using a completely randomized design with four replications performed in a replacement series. The ratios of soybean and to susceptible (experiment 1) and resistant ryegrass (experiment 2) and of susceptible to resistant (experiment 3) ryegrass were 100:0, 75:25, 50:50, 25:75 and 0:100. Forty days after the emergence of the soybean crop and 60 days after the emergence of the ryegrass...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oxidative stress; Antioxidant enzymes; Adaptability of herbicide resistant plants.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000300517

Influence of Nitrogen Fertilization on Herbicide Selectivity in Rice
Provedor de dados: Planta Daninha
Autores: LANGARO,A.C.; AGOSTINETTO,D.; OLIVEIRA,C.; FRANCO,J.J.; ZANDONÁ,R.R.; VARGAS,L.
ABSTRACT: Chemical weed control and nitrogen fertilization are common practices in irrigated rice crops. Nitrogen is an essential element for growth and development of plants and may influence herbicide selectivity. In this study, herbicide selectivity was evaluated according to nitrogen application time in irrigated rice crops. The experiment was conducted in the field in a split-plot design with four replications. Treatments were arranged in a factorial scheme: factor A consisted of different nitrogen application times (without nitrogen, all nitrogen applied before flooding, half of the nitrogen rate applied before flooding and the other half after flooding, all nitrogen applied after flooding); factor B consisted of the application of the herbicides...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Nitrogen; Selectivity; Weeds.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100318

Partitioning of Competition for Resources Between Soybean and Corn as Competitor Plant
Provedor de dados: Planta Daninha
Autores: CARATTI,F.C.; LAMEGO,F.P.; SILVA,J.D.G.; GARCIA,J.R.; AGOSTINETTO,D.
ABSTRACT Plants compete for resources present below and above the soil surface. The objective of this work was to separate the individual effects of the competition for resources between soybean and corn as competitor plants. The experiment was conducted in a greenhouse, in 2014/2015. The treatments consisted of soybean cultivars (TEC 5718 and TEC 6029) in competition conditions with corn (no competition, competition for soil resources, competition for solar radiation and total competition). The variables evaluated were plant height at 7, 14, 21, 28, 35 and 42 days after emergence (DAE), stem/culm diameter, leaf area, shoot dry mass, root dry mass and the chlorophyll index, at 42 (DAE). The competition for soil resources between soybean and corn is...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Zea mays; Water; Competitiveness; Solar radiation; Competitor plant.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000400657

Glyphosate Resistance Affect the Physiological Quality of Conyza bonariensis seeds
Provedor de dados: Planta Daninha
Autores: PIASECKI,C.; MAZON,A.S.; AGOSTINETTO,D.; VARGAS,L.
ABSTRACT: High seed production and dispersal capacity and glyphosate resistance are among the main factors that have made hairy fleabane (Conyza bonariensis) one of the most important and dispersed weeds in the world. Herbicide-resistant weeds populations may have fitness cost due to molecular, physiological, and biochemical changes. This study aimed to evaluate the physiological quality of seeds of Conyza spp. and determine whether glyphosate resistance causes fitness costs for resistant biotypes. Seeds from six hairy fleabane biotypes, three glyphosate-resistant and three -sensitive, with a resistance factor average of 11.7 were studied. Among the studied biotypes, five were identified as C. bonariensis and one as C. blakei. Seed analyses were performed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Herbicide resistance; Integrated weed management; Weed biology; Soil seed bank; Conyza blakei.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100157

Does the Glyphosate Treatment Interfere Negatively on RNA Integrity in Glyphosate-Resistant and -Sensitive Conyza bonariensis?
Provedor de dados: Planta Daninha
Autores: PIASECKI,C.; BENEMANN,D.; CARVALHO,I.R.; AGOSTINETTO,D.; STEWART Jr.,C.N.; VARGAS,L.
ABSTRACT: The hairy fleabane ( Conyza bonariensis (L.) Cronq.) is among the most problematic glyphosate-resistant weeds to manage around the world. In weed science, molecular approaches such as RNA sequencing (RNA-Seq) and quantitative reverse-transcription polymerase chain reaction (RT-qPCR) have been employed to study molecular responses to glyphosate treatment in  Conyza species. Glyphosate treatment leads to reactive oxygen species (ROS) production in plants which could damage the RNA. Degraded RNA is an issue and can compromise further molecular analysis. Thus, the objective of this study was to evaluate whether glyphosate treatment interferes negatively on RNA integrity of glyphosate-resistant and -sensitive hairy fleabane biotypes. Two experiments...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hairy fleabane; Molecular analysis; RNA integrity number (RIN).
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100175

CARACTERIZAÇÃO MORFOANATÔMICA, CONTAGEM CROMOSSÔMICA E VIABILIDADE POLÍNICA DE BIÓTIPOS DE AZEVÉM SUSCETÍVEL E RESISTENTES AO HERBICIDA GLYPHOSATE
Provedor de dados: Planta Daninha
Autores: RUCHEL,Q.; VARGAS,L.; AGOSTINETTO,D.; FERNANDO,J. A.; LÜDTKE,R.; BOBROWSKI,V. L.
RESUMOO azevém é uma planta daninha de ciclo anual, encontrada em praticamente todas as lavouras de inverno, em pomares e vinhedos da região Sul do Brasil. A espécie é normalmente controlada pelo herbicida glyphosate, no entanto, o uso continuado desse produto selecionou biótipos resistentes. Diferenças na suscetibilidade do azevém a herbicidas têm sido atribuídas a características morfológicas, anatômicas e genéticas das plantas. Os objetivos deste trabalho foram realizar a caracterização morfoanatômica, adequar metodologia para a análise citológica de cromossomos e indicar corantes para testes de viabilidade polínica de biótipos de azevém suscetível e resistentes ao herbicida glyphosate. As sementes dos biótipos de azevém suspeitos de resistência...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anatomia; Cromossomos; Lolium multiflorum; Morfologia; Poaceae.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582015000300567

Interference Periods in Soybean Crop as Affected by Emergence Times of Weeds
Provedor de dados: Planta Daninha
Autores: ZANDONÁ,R.R.; AGOSTINETTO,D.; SILVA,B.M.; RUCHEL,Q.; FRAGA,D.S.
ABSTRACT: Weeds emergence times modify competition with crops. Thus, the hypothesis was that the increase in weed emergence flow decreases the period prior to interference (PPI) in soybeans and increases the critical period of interference prevention (CPIP). The objective was to determine the PPI and the CPIP of weeds in soybean crops as affected by the preferred time of weeds emergence flow. Three experiments were conducted in the field in a randomized block design with four replications. The treatments were arranged in a factorial design with factor A consisting of coexistence or weed control in soybeans and factor B for eight periods (0, 7, 14, 21, 28, 35, 42 and 135 days after crop emergence (DAE)). The numbers of emerged plants and weed dry mass by...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Weed competition; Crop yield losses.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100246

Fitness Cost and Competitive Ability of Ryegrass Susceptible and with Multiple Resistance to Glyphosate, Iodosulfuron-Methyl, and Pyroxsulam
Provedor de dados: Planta Daninha
Autores: HENCKES,J.R.; CECHIN,J.; SCHMITZ,M.F.; PIASECKI,C.; VARGAS,L.; AGOSTINETTO,D.
ABSTRACT: Ryegrass is an important weed in wheat cultivations due to the evolution of resistance to different mechanisms of action. This study aimed to compare the phenological development, fitness cost, and competitive ability between ryegrass biotypes susceptible and with multiple resistance to 5-enolpyruvylshikimate-3-phosphate synthase (EPSPs) and acetolactate synthase (ALS) inhibiting herbicides. Fitness cost and phenological development were evaluated from biotypes grown in pots, and morphological growth variables were determined up to 140 days after emergence. Phenological development was evaluated with a fitness cost. Competitive ability was determined in a replacement-series experiment with proportions of resistant and susceptible ryegrass. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lolium multiflorum; EPSPs; ALS; Competition.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100288

Physiological Performance of Seeds and Level of Herbicide Residues Depending on Application of 2.4-D in Wheat
Provedor de dados: Planta Daninha
Autores: AISENBERG,G.R.; WESTENDORFF,N.R.; LANGARO,A.C.; VARGAS,L.; AGOSTINETTO,D.
ABSTRACT: Horseweed control through application of 2.4-D in the winter season is an alternative to manage biotypes resistant to herbicides that belong to other mechanisms of action. The objectives of this study were to assess the physiological quality of wheat seeds and determine the rate of 2.4-D residue, as function of application stages and herbicide rates. The treatments were arranged in factorial scheme, with three application stages (flowering, soft dough and hard dough), and four 2.4-D rates (0; 504; 1,008 and 2,015 g a.i. ha-1). The application of 2.4-D in the wheat crop changed physiological seed quality by increased the rate and total percentage of germination. The application of 2.4-D resulted in herbicide accumulation in seeds, especially when...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Triticum aestivum; Weeds; Germination; Dry matter.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100205

COMPETITION BETWEEN WHEAT AND RYEGRASS UNDER DIFFERENT LEVELS OF NITROGEN FERTILIZATION
Provedor de dados: Planta Daninha
Autores: AGOSTINETTO,D.; TAROUCO,C.P.; LANGARO,A.C.; GOMES,J.; VARGAS,L.
ABSTRACT The main limiting factors for the productive potential of wheat crops are related to the competition with weeds for resources such as water, light and nutrients. Nitrogen (N) is an important nutrient used to maintain crop productivity, as well as promoting the competitive ability of crops and therefore suppress the weed growth. In this context, the goal of this study was to evaluate the effects of wheat plants in competition with ryegrass under different levels of nitrogen fertilization. Treatments were arranged in a factorial design, where factor A consisted in nitrogen rates (0, 60, 120, 180 and 240 kg ha-1) and factor B consisted in ryegrass and wheat plants ratios, which were: 100/0 (pure stand of 64 wheat plants), 50/50 (32 wheat plants and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nitrogen; Replacement series; Triticum aestivum; Lolium multiflorum.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100247

Drift Distance in Aircraft Glyphosate Application Using Rice Plants as Indicators
Provedor de dados: Planta Daninha
Autores: CÓRDOVA,R.A.; TOMAZETTI,M.; REFATTI,J.P.; AGOSTINETTO,D.; AVILA,L.A.; CAMARGO,E.R.
ABSTRACT: This study aimed to evaluate the potential for glyphosate drift during aerial application using rice plants as sentinels, aiming to determine the effect of drift on irrigated rice crops. For this purpose, a field experiment was performed using an entirely randomized design with four replicates, evaluating different distances from the site of application [control (no application), 0, 12.5, 25, 50, 75, 100, 150, 200, 300, and 400 m]. The experiment was carried out at the Granjas 4 Irmãos farm, located in the Rio Grande city, Rio Grande do Sul State, Brazil. The glyphosate dose application was 1,920 g e.a. ha-1 (Roundup Transorb®, 480 g e.a. L-1 glyphosate isopropylamine salt). A dose-response curve was developed to estimate the drift rate in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: EPSPs injury; Phytotoxicity; Productivity; Sub-doses.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582020000100248

Interference Periods of Raphanus raphanistrum L. in Sunflower Crop
Provedor de dados: Planta Daninha
Autores: AGOSTINETTO,D.; WESTENDORFF,N.; ZANDONÁ,R.R.; ULGUIM,A.R.; LANGARO,A.C.
ABSTRACT: Raphanus raphanistrum L. (wild radish) stands out among the weeds that cause greatest damage to the sunflower crop, due to the development cycle and adaptability. The objective of this research was to determine interference periods of sunflower interacting with wild radish, and the effects of competition on yield and its components. The experiment was conducted in the field in a randomized block design with four replications. The treatments were arranged in a factorial design with factor A composed of wild radish coexistence or control in sunflower, and factor B, for eight periods (0, 7, 14, 21, 28, 35, 42 and 135 days after crop emergence). It was evaluated height, diameter of chapters, achene yield and dry matter of weeds and crop. The presence...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Helianthus annuus; Competition; Weeds.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582020000100240

Quick Test for Detecting Glyphosate-Resistant Ryegrass Seeds
Provedor de dados: Planta Daninha
Autores: SCHMITZ,M.F.; ZANDONÁ,R.R.; VARGAS,A.A.M.; GARCIA,J.R.; TUNES,L.V.M.; AGOSTINETTO,D.
ABSTRACT: The commercialization of ryegrass seeds with the presence of resistant biotypes is a serious issue that increses the dispersion of resistance to new areas without this problem. Therefore, this study aimed to develop a quick test to detect susceptible and resistant seeds to the glyphosate herbicide in order to identify contaminated seed lots with glyphosate resistance. Three experiments were carried out, one in greenhouse and the other two in the seed laboratory. First, the resistance factor (RF) was determined by a dose-response curve experiment in biotypes suspected to be resistant and susceptible to glyphosate. Then, the germination test was conducted with the selected biotypes under increasing glyphosate rates (0, 3.5, 6.9, 13.9, 27.8, 55.5,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lolium multiflorum; Germination; Herbicide; Methodology.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100243

Resistance Mapping of the Genus Cyperus in Rio Grande do Sul and Selection Pressure Analysis
Provedor de dados: Planta Daninha
Autores: ULGUIM,A.R.; SILVA,B.M.; AGOSTINETTO,D.; AVILA NETO,R.C.; ZANDONÁ,R.R.
ABSTRACT: Among the species of the genus Cyperus occurring in paddy rice, C. esculentus, C. difformis and C. iria are the most important, and the latter two are reported as resistant to herbicides in Rio Grande do Sul (RS). The aim of this work was to characterize and mapping the occurrence of resistant plants of the genus Cyperus in areas of paddy rice in RS State, and to analyze the agronomic factors that interfere in the resistance selection. Seeds from individual plants were harvested in the 2014/15 crop, characterized as control failures by the application of acetolactate synthase inhibitors (ALS), totaling 43 samples. At the time of collection, the grower was inquired on aspects related to the management of weeds in the crop. Seeds were germinated in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Acetolactate synthase; Cyperus esculentus; C. iria; C. difformis; Irrigated rice.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100254

Geographic Distribution of Ryegrass Resistent to the Clethodim Herbicide in Rio Grande do Sul1
Provedor de dados: Planta Daninha
Autores: VARGAS,L.; SCHNEIDER,T.; AGOSTINETTO,D.; BIANCHI,M.A.
ABSTRACT Ryegrass is a weed of annual cycle that is present in winter crops, in orchards and vineyards of the South region of Brazil. The species is normally controlled by the glyphosate herbicide, but the continuous use of this product caused the selection of resistant biotypes. The use of ACCase inhibitor herbicides is the main alternative for the control of this species, but it has not been satisfactory in some places, thus causing suspicion of resistance to this action mechanism. Thus, the objective of this paper was to evaluate the occurrence and geographic distribution of ryegrass biotypes that are resistant to the clethodim herbicide in the state of Rio Grande do Sul. For that, seeds of ryegrass plants that survived the application of clethodim were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lolium multiflorum; Resistance; Chemical control; Acetyl coenzyme A carboxylase.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000200365

MOLECULAR CHARACTERIZATION OF HAIRY FLEABANE USING RAPD
Provedor de dados: Planta Daninha
Autores: SILVA,D.R.O.; AGOSTINETTO,D.; VARGAS,L.
ABSTRACT With the increase of glyphosate resistance evolution in hairy fleabane, the knowledge of genetic diversity is essential to assist in the weed management. The objective was to characterize the genetic diversity of glyphosate resistant Conyza species in Rio Grande do Sul. Hairy fleabane biotype seeds were collected in fields of glyphosate-resistant soybean, generating seedlings used for extracting DNA from the leaves to perform a genetic diversity analysis, using the RAPD technique. The DNA was used in polymerase chain reaction and DNA fragments were assessed for polymorphism bands in electrophoresis. Biotypes were identified as Conyza bonariensis and microcephala varieties. In molecular analysis, among 25 primers RAPD, eight were reproducible...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conyza bonariensis; Polymorphism; Glyphosate; PCR.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000300433

VERIFICATION OF THE MECHANISM OF GLYPHOSATE RESISTANCE IN ITALIAN RYEGRASS BIOTYPES
Provedor de dados: Planta Daninha
Autores: VARGAS,L.; RUCHEL,Q.; AGOSTINETTO,D.; LAMEGO,F.P.; LANGARO,A.C.; PIESANTI,S.R.
ABSTRACT The intense use of glyphosate for weed control led to the emergence of several cases of resistance to this herbicide. Weeds can survive the application of herbicides due to several factors, which may or may not be related to the herbicide site of action. The objectives of this study were to quantify the accumulation of shikimate in ryegrass biotypes in response to glyphosate application; investigate possible mutations on the EPSPs gene in susceptible and resistant biotypes; and evaluate the response of ryegrass biotypes to the application of glyphosate after treatment with a metabolism inhibitor of cyt P450 monooxygenase. The seeds of ryegrass biotypes with suspected resistance came from the municipality of São Valentim, RS (SVA 1 and SVA 4) and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Shikimic acid; EPSPs; Lolium multiflorum; Metabolism.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000300565

INVESTIGATION OF THE MECHANISM OF RESISTANCE TO GLYPHOSATE HERBICIDE IN HAIRY FLEABANE
Provedor de dados: Planta Daninha
Autores: KASPARY,T.E.; LAMEGO,F.P.; LANGARO,A.C.; RUCHEL,Q.; AGOSTINETTO,D.
ABSTRACT The resistance of weeds to herbicides is a consequence of one or more mechanisms in the plant, responsible for not allowing the herbicide to act properly at the active site. The objective of this study was to investigate the mechanism(s) of resistance to glyphosate in Conyza bonariensis. An experiment was conducted in November and December, 2012 and repeated in February and March, 2013 using a factorial arrangement of the treatments, where the factor A corresponded to biotypes of hairy fleabane, susceptible (S) and resistant (R); the factor B to seven rates of glyphosate from 0 to 11,520 g e.a. ha-1, and factor C were simulated environmental conditions of winter (12/8 oC day/night of temperature and 10/14 h of photoperiod) and summer (28/20 oC...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conyza bonariensis; Temperature; Photoperiod; EPSPs.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000300555

Evaluation of the Mechanism Responsible for the Low-Level Resistance to Glyphosate in Goosegrass
Provedor de dados: Planta Daninha
Autores: ULGUIM,A.R.; FRANCO,J.J.; SILVA,J.D.G.; AGOSTINETTO,D.; VARGAS,L.
ABSTRACT Goosegrass (Eleusine indica) infests various crops, being reported as low-level resistant (LLR) to glyphosate. The objectives of this study were to evaluate the mechanisms of resistance to glyphosate in goosegrass by the cyt-P450 complex to identify changes in leaf anatomy of these plants and quantify the accumulation of shikimate in biotypes susceptible and with LLR. The metabolic rate was assessed by applying the cyt-P450 malathion inhibitor 30 minutes before the herbicide application. The analysis of the leaf anatomy consisted of a characterization of anatomic cross-sections and evaluation of the effect of glyphosate on the leaf epidermis and the conducting vessels. Plant tissue was collected 24 hours after treatment (HAT) of the dose-response...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cyt-P450 monooxygenase; Shikimate; Absorption and translocation; EPSPs; Eleusine indica.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100206

Morphological and Metabolic Changes in Soybean Plants Cultivated in Irrigated Rice Rotation and as Affected by Imazapyr and Imazapic Herbicides Carryover
Provedor de dados: Planta Daninha
Autores: FRAGA,D.S.; AGOSTINETTO,D.; LANGARO,A.C.; OLIVEIRA,C.; ULGUIM,A.R.; SILVA,J.D.G.
ABSTRACT: The appearance of soybean cultivars that are tolerant to herbicides from the imidazolinone group enables irrigated rice rotation conducted on Clearfield® system. The objective of this work was to evaluate the morphological and metabolic changes of soybean cultivars containing Cultivance® (CV), which is tolerant to imidazolinone, sulphonylurea toletant (STS) and Roundup Ready® (RR), which is tolerant to glyphosate as affected by carryover of increasing doses of imazapyr and imazapic herbicides mixture, applied in the management of irrigated rice crop. Thus, experiments were conducted on the field and in greenhouse, evaluating phytotoxicity, height, leaf area, shoot dry matter, as well as variables related to the secondary metabolism of plants like...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Imidazolinones; Glicine max; Reactive oxygen species.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100211

IDENTIFICATION AND VALIDATION OF REFERENCE GENES FOR THE NORMALIZATION IN REAL-TIME RT-QPCR ON RICE AND RED RICE IN COMPETITION, UNDER DIFFERENT NITROGEN DOSES
Provedor de dados: Planta Daninha
Autores: BENEMANN,D.P.; NOHATO,A.M.; VARGAS,L.; AVILA,L.A; AGOSTINETTO,D.
ABSTRACT Real time reverse transcription polymerase chain reaction (RT-qPCR) is an important technique to analyze differences in gene expression due to its sensitivity, accuracy, and specificity. However, before analyzing the expression of the target gene, it is necessary to identify and evaluate the stability of candidate reference genes for the proper normalization. This study aimed at evaluating the stability of candidate reference genes in order to identify the most appropriate genes for the normalization of the transcription in rice and red rice in competition under different nitrogen levels, as well as to demonstrate the effectiveness of the reference gene selected for the expression of the cytosolic ascorbate peroxidase (OsAPX2). Eleven candidate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Gene expression; Normalization.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100215