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| Registros recuperados: 141 | |
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| FERREIRA,S.D.; EXTECKOETTER,V.; GIBBERT,A.M.; BARBOSA,J.A.; COSTA,N.V.. |
| ABSTRACT: Selecting glyphosate-resistant Digitaria insularis may cause changes in the biological cycle of the species. Therefore, the objective of this study was to evaluate the biological cycle of susceptible and glyphosate-resistant D. insularis biotypes in two growth periods (summer/autumn and autumn/winter). Seeds were collected in the municipality of Alagoa Grande (07o02’59" S 35o37’01,5" W), and were considered susceptible (S1), in Cascavel (24o55’27" S 53o27’54.6 ”W) considered as resistant 1 (R1), Entre Rios do Oeste (24o40’44" S 54o17’05" W) considered as resistant 2 (R2) and Marechal Cândido Rondon (24o42’30" S 54o21’10" W) considered as resistant 3 (R3). Evaluations were carried out in the summer/autumn and autumn/winter periods. The collection... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Digitaria insularis; Growth analysis; Weed; Chemical control. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100276 |
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| Machado,E.C.R.; Lima,R.S.O.; Silva,A.P.P.; Marques,B.S.; Gonçalves,M.F.; Carvalho,S.J.P.. |
| Availability of basic information on weed biology is an essential tool for designing integrated management programs for agricultural systems. Thus, this study was carried out in order to calculate the base temperature (Tb) of southern sandbur (Cenchrus echinatus), as well as fit the initial growth and development of the species to accumulated thermal units (growing degree days - GDD). For that purpose, experimental populations were sown six times in summer/autumn conditions (decreasing photoperiod) and six times in winter/spring condition (increasing photoperiod). Southern sandbur phenological evaluations were carried out, on alternate days, and total dry matter was measured when plants reached the flowering stage. All the growth and development fits were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cenchrus echinatus; Weed; Biology; Growing degree days; Modeling. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582014000200011 |
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| COSTA,N.V.; FERREIRA,S.D.; RAMELLA,J.R.; MORATELLI,G.; DOURADO,R.F.. |
| ABSTRACT Weeds have the potential to dramatically interfere in cassava cultivation, reducing its productive potential; however, there are few studies on the selective herbicides in this crop. Therefore, the objective was to evaluate in this work the selectivity and efficiency of sulfentrazone in cassava crops grown in sandy and clayey soils. Two experiments were carried out: The first one was carried out in sandy soil conditions in the conventional system; and the second one was carried out in clayey soil conditions in the no-tillage system. The experimental design was a randomized block with four replications. The treatments consisted in doses of 250, 500, 750 and 1,000 g ha-1 of sulfentrazone, and weeded and non-weeded controls. Sulfentrazone application... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chemical control; Protox inhibitors; Weed; Manihot esculenta. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582015000400787 |
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| SILVA JR.,A.C.; GONÇALVES,C.G.; SCARANO,M.C.; PEREIRA,M.R.R.; MARTINS,D.. |
| ABSTRACT: The action of herbicides on weeds that develop under water deficit can be compromised, because the routes of penetration of hydrophilic herbicides are reduced due to the lower hydration of the cuticle in these plants. Moreover, hydrophobic compounds found in the epicuticular wax coating of plants under water stress, hinder the penetration of hydrophilic compounds. This study evaluated the control efficiency of glyphosate on guineagrass plants when submitted to different water deficits. The study was conducted in a greenhouse, and treatments were composed of guineagrass plants submitted to three soil water conditions [low water deficit (13%), intermediate water deficit (10%) and high water restriction (8%)], three doses of glyphosate (0.0, 270.0... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicide; Water deficit; Weed; Panicum maximum. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100320 |
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| CARRARO-LEMES,C.F.; SCHEFFER-BASSO,S.M.; DEUNER,C.C.; BERGHAHN,S.C.T.. |
| ABSTRACT: The recognized allelopathic activity of oats as a soil-cover plant induces the study of the potential of their germplasm. The objective of this study is to verify if there is genotype variability in the Avena spp. with regard to allelopathic activity. Extracts of A. strigosa ‘Agro Quaraí’, ‘Agro Esteio’, ‘Embrapa139’, ‘AF 12104’, ‘AF 12109’, ‘AF 12202’, ‘AF 12209’, A. sativa ‘UPFPS Farroupilha’ and ‘AF 1345 Ucraniana,’ were prepared in three concentrations w/v (5 g, 10 g, and 20 g of dry mass 100 mL-1). The experiment was conducted in a germination chamber for 15 days, with lettuce (Lactuca sativa L.) as the recipient plant. There was complete inhibition of germination under 20% w/v extracts and partial inhibition at 10% w/v. Only 5% w/v observed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Avena sativa L.; Avena strigosa Schreb; Weed; Germination; Inhibition. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100297 |
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| DEISS,L.; MORAES,A.; PELISSARI,A.; PORFÍRIO-DA-SILVA,V.; DOMINSCHEK,R.. |
| ABSTRACT: Trees in integrated crop-livestock systems can reduce infestation and dispersion of weeds because of a negative interference promoted by competition for light, water and nutrients. The objective of this study was to evaluate the infestation and dispersion of sticky nightshade (Solanum sisymbriifolium) in soybean in different positions between eucalyptus (Eucalyptus dunnii) double rows [20 m x (4 m x 3 m)] in an integrated crop-livestock system at Subtropical Brazil. The experiment was conducted in a randomized block design, with nine replications, and five equidistant positions between double rows (n=45) as treatments. Sticky nightshade was evaluated for infestation through biomass, plant density (reproductive and vegetative plants), and for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Integrated crop-livestock systems; Weed; Alley cropping; Ecophysiology; Agroforestry. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100207 |
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| McElroy,J.S.; Martins,D.. |
| In crop production, weeds must be controlled so as not to adversely affect crop yield and crop quality. Thus, a low level of weeds infesting a field, in most instances, is not a problem. Except in sod or seed production, turfgrass does not have a yield component. The value of turfgrass is its inherent aesthetic quality and usability. Aesthetic quality is the beauty and value that turfgrass adds to a managed landscape. Usability can be the durability of a sport field, trueness of golf putting green roll, or reduction in soil loss from water runoff or wind. Any weed presence in turfgrass can decrease the aesthetic quality and usability of turfgrass. Utilizing herbicides is the only way to completely control weeds in a turfgrass stand. While it is possible to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Preemergence; Postemergence; Selectivity; Chemical control; Weed. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000200024 |
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| Soltani,E; Soltani,A; Galeshi,S; Ghaderi-far,F; Zeinali,E. |
| Volunteer canola (Brassica napus) and Sinapis arvensis are well identified weeds of different cropping systems. Quantitative information on regarding seed production by them is limited. Such information is necessary to model dynamics of soil seed banks. The aim of this work was to quantify seed production as a function of the size of those weeds. A wide range of plant size was produced by using a fan seeding system performed at two sowing dates (environments). Plant size varied from 3 to 167 g per plant for canola and from 6 to 104 g per plant for S. arvensis. Seed production ranged from 543 to14,773 seeds per plant for canola, and from 264 to 10,336 seeds per plant for S. arvensis. There was a close relationship between seed production per plant and plant... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Weed; Plant size; Density; Planting. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582011000300003 |
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| BRITO,I.P.F.S.; MARCHESI,B.B.; TROPALDI,L.; CARBONARI,C.A.; VELINI,E.D.. |
| ABSTRACT: This study aimed to assess the response of Urochloa decumbens plants to different doses of glufosinate ammonium, and the sensitivity of plant population to the herbicide. Two studies were conducted, both in greenhouse and repeated at different times. In the dose-response analysis, two experiments were conducted using seven doses of the glufosinate ammonium (0, 50, 100, 200, 400, 800, and 1,600 g a.i. ha-1) with four replications each. In the analysis of sensitivity levels of U. decumbens to herbicide, 44 plants were sprayed with a dose of 200 g a.i. ha-1 of the herbicide. Tissue ammonium content was determined, and injury percentage was visually assessed. Experiment data were converted to mg of ammonium per kg-1 of fresh mass and submitted to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ammonia; Glutamine synthetase; Weed; Variability. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100238 |
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| AKHTAR,R.; JAVAID,A.. |
| ABSTRACT: Onion is attacked by destructive soil-borne fungal plant pathogen Fusarium oxysporum f. sp. cepae, resulting in basal rot disease. In the present study, three Trichoderma species (T. pseudokoningii, T. harzianum and T. reesei) and leaves of solanaceous weed Withania somnifera were used for management of this disease. The in vitro interaction study revealed T. harzianum as the most effective biocontrol agent against the pathogen. In a pot trial, dried leaf material of W. somnifera (1%, 2% and 3% w/w) and inoculum of T. harzianum were mixed in the pot soil previously inoculated with the pathogen. The highest incidence of the disease (87%) was found in positive control (pathogen inoculation without any amendment). Different rates of dry leaf... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Basal plate rot; Biological control; Weed; Withania somnifera. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100216 |
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| Sadeghloo,A.; Asghari,J.; Ghaderi-Far,F.. |
| Abutilon theophrasti and Barnyardgrass (Echinochloa crus-galli) are major weeds that affect cropping systems worldwide. Laboratory and greenhouse studies were conducted to determine the effects of temperature, pH, water and salinity stress, and planting depth on seed germination and seedling emergence of Velvetleaf and Barnyardgrass. For Velvetleaf, the base, optimum and ceiling germination temperatures were estimated as 5, 35 and 48 ºC, respectively. Seed germination was sensitive to drought stress and completely inhibited by a potential of -0.6 MPa, but it was tolerant to salinity. Salinity stress up to 45 mM had no effect on the germination of Velvetleaf, but germination decreased with increasing salt concentration. Drought and salinity levels for 50%... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: PH; Planting depth; Seed germination; Temperature; Weed. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000200003 |
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| Chalak, Morteza; Pannell, David J.. |
| Weeds can cause significant problems to natural ecosystems. Although there have been numerous studies on the economics of weed control, relatively few of these studies have focused on natural ecosystems. This paper addresses this gap in the literature by assessing the cost-effectiveness of a comprehensive range of control strategies for blackberry (Rubus anglocandicans) in natural environments in Australia. We developed a stochastic dynamic simulation model and a deterministic dynamic optimisation model. The stochastic model calculates the expected net present value (NPV) of a range of control strategies, including any combination of treatment options. The optimisation model identifies the treatment combination that maximises NPV. Both models represent the... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Environment; Economics; Weed; Stochastic; Optimisation; Management; Environmental Economics and Policy. |
| Ano: 2011 |
URL: http://purl.umn.edu/108416 |
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| Chalak, Morteza; Pannell, David J.. |
| Although there have been numerous studies on the economics of weed control, relatively few of these studies have focused on natural ecosystems. The aims of this papers are: A) to identify the combination of control options that is optimal for blackberry (Rubus anglocandicans) in Australian natural ecosystems, B) to assess whether an integrated control strategy is superior to chemical-only strategies, C) to evaluate the economic net benefits of specific biologically oriented control methods (a rust and grazing by goats), D) to determine how changes in model parameters affect the optimal control strategy. To address these aims, a stochastic dynamic simulation model and a stochastic dynamic programming model are developed. The results indicate that, while an... |
| Tipo: Presentation |
Palavras-chave: Environment; Economics; Weed; Stochastic; Optimisation; Management; Environmental Economics and Policy. |
| Ano: 2012 |
URL: http://purl.umn.edu/124373 |
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| Chalak-Haghighi, Morteza; Pannell, David J.. |
| Weeds can cause significant problems to natural ecosystems. Although there have been numerous studies on the economics of weed control, relatively few of these studies have focused on natural ecosystems. This paper addresses this gap in the literature by assessing the cost-effectiveness of a comprehensive range of control strategies for blackberry (Rubus anglocandicans) in natural environments in Australia. We developed a stochastic dynamic simulation model and a deterministic dynamic optimisation model. The stochastic model calculates the expected net present value (NPV) of a range of control strategies, including any combination of treatment options. The optimisation model identifies the treatment combination that maximises NPV. Both models represent the... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Environment; Economics; Weed; Stochastic; Optimisation; Management; Environmental Economics and Policy. |
| Ano: 2010 |
URL: http://purl.umn.edu/58886 |
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| Barros,Renato T. de; Martins,Cibele C.; Silva,Givanildo Z. da; Martins,Dagoberto. |
| ABSTRACT The invasive behavior of beggarticks (Bidens pilosa L.) in cropped areas is due to its ecological adaptation and aggressive regeneration, which is dependent on seed germination. The objective of this research was to verify the effects of B. pilosa seed origin and temperature on seed germination. The seeds were collected in Entre Rios do Oeste, PR, Botucatu, SP, Capão Bonito, SP, São Joaquim da Barra, SP, Sertãozinho, SP, Selvíria, MS, Barra do Garças, MT, Areia, PB and Manaus, AM. The seeds were evaluated regarding moisture content, 1000-seed weight, germination speed index and germination at 60 days (normal seedlings, dormant seeds and dead seeds) at the temperatures of 10, 15, 20, 25, 30, 35, 40, and 45 ºC. The replicates were distributed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bidens pilosa; Weed; Production sites; Dormancy. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000700448 |
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| Domingos,Vanessa D.; Martins,Dagoberto; Costa,Neumarcio V.; Costa,Andreia C. P. R. da; Marchi,Sidnei R. de. |
| ABSTRACT The objective of this study was to evaluate the initial growth of emergent plants of Brachiaria subquadripara under different conditions of availability levels of the nutrients nitrogen (N), phosphorus (P), and potassium (K) provided to the plants via nutrient solution in a greenhouse. The treatments consisted of five concentrations of N (0, 42.0, 84.0, 126.0, and 168.0 mg L-1), five concentrations of P (0, 6.2, 12.4, 18.6, and 24.8 mg L-1) and five concentrations of K (0, 46.8, 93.6, 140.4, and 187.2 mg L-1) which were adapted from a base solution. The results showed that the initial growth of plants was slow up to 21 days after transplantation (DAT) and it increased in accordance with increments in N, P, and K concentrations in the nutrient... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Urochloa subquadripara; Urochloa arrecta; Aquatic plant; Weed; Eutrophication; Water reservoir. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662015000600560 |
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| Registros recuperados: 141 | |
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