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| Registros recuperados: 72 | |
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| Cacho, Oscar J.; Jones, Randall E.. |
| It is argued in this paper that static approaches to weed management, where the benefits and costs are only considered within a single season, are inappropriate for assessing the economic benefits of weed control technologies. There are carryover effects from weed management as weeds that escape control in one season may reproduce and replenish weed populations in following seasons. Consequently, it is appropriate to view weed control in the context of a resource management problem where the goal is to determine the optimal inter-temporal level of weed control that maximises economic benefits over some pre-determined period of time. A dynamic optimisation model for weed control is presented. Using the tools of comparative static analysis and Pontryagin's... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Weed control; Resource economics; Optimal control; Dynamic programming; Wild oats; Farm Management. |
| Ano: 2000 |
URL: http://purl.umn.edu/12902 |
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| HUSSAIN,M.I.; QAMAR ABBAS,S.; REIGOSA,M.J.. |
| ABSTRACT: This review covers biological activity of secondary metabolites, coumarin and their derivatives on different organisms (pests, pathogens, weeds), as well as their applications in agriculture as eco-friendly pesticides and weed control agents. Naturally occurring coumarins have shown biological and allelopathic potential on a broad range of organisms. Coumarin inhibits seed germination, root growth, morphology, histology, water uptake, respiration, photosynthesis, cell elongation, cell división and differentiation. Coumarin demonstrate excellent insecticidal potential against eggs, larvae and adult insects. Coumarin showed antifeedent responses in a wide range of memebers from invertebrates to vertebrates. The information provided in this review... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coumarin; Secondary metabolites; Multifunctionality; Herbivory; Allelopathy; Phytotoxicity; Weed control. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100220 |
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| 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 |
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| Reigosa,Manuel; Gomes,Anabele Stefânia; Ferreira,Alfredo Gui; Borghetti,Fabian. |
| In this article, we review allelopathy studies conducted in Brazil or involving plant species that occur in the country. Conceptions and misconceptions associated with allelopathy, as well as some international criteria to be applied in allelopathic research, are presented and discussed. We observed a sharp increase in the number of papers on this subject conducted in Brazil between 1991 and 2010. However, most studies are conducted under laboratory conditions, lack a clear hypothesis or a solid justification, and typically make use of target species that do not co-exist with the donor species under natural conditions. We also found that most studies do not take the additional steps in order to purify and identify the bioactive molecules. We recommend that... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Allelochemicals; Competition; Interference; Phytotoxicity; Weed control. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000400001 |
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| Cacho, Oscar J.; Hester, Susan M.; Spring, Daniel. |
| The detectability of invasive organisms influences the feasibility of eradicating an infestation. Search theory offers a framework for defining and measuring detectability, taking account of searcher ability, biological factors and the search environment. In this paper, search theory concepts are incorporated into a population model, and the costs of search and control are calculated as functions of the amount of search effort (the decision variable). Simulations are performed on a set of weed scenarios in a natural environment, involving different combinations of plant longevity, seed longevity and plant fecundity. Results provide preliminary estimates of the cost and duration of eradication programs to assist in prioritising weeds for control. The... |
| Tipo: Article |
Palavras-chave: Bioeconomics; Invasive species; Operations research; Population dynamics; Weed control; Resource /Energy Economics and Policy. |
| Ano: 2007 |
URL: http://purl.umn.edu/118522 |
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| 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 |
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| PARDO,G.; MARTÍNEZ,Y.. |
| ABSTRACT: Weed control is a crucial aspect in many conservation agriculture systems given that costs and time savings from avoiding tillage are closely linked to the use of effective and environmental friendly herbicides. This has led to the widespread use of glyphosate in farms, as it is a broad-spectrum, easily degradable, low- cost herbicide. The recent debate on the safety of glyphosate and on the excessive use of chemical herbicides in food production has caused concern on farmers about the possible economic effects of a virtual ban on glyphosate. The aim of this paper is to estimate the costs associated with an eventual prohibition of glyphosate in Spanish conservation agriculture areas. The costs of different alternative weed control strategies for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Conservation systems; Conventional tillage; Economic evaluation; Weed control. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100166 |
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| GONÇALVES NETTO,A.; NICOLAI,M.; CARVALHO,S.J.P.; MALARDO,M.R.; LÓPEZ-OVEJERO,R.F.; CHRISTOFFOLETI,P.J.. |
| ABSTRACT: The emergence of resistant biotypes of the Amaranthus palmeri species in cotton production areas of the state of Mato Grosso, Brazil, generated the need for correct identification of this species and information on viable herbicidal tools for their management. Thus, greenhouse experiments were conducted to evaluate the efficacy of alternative herbicides applied to A. palmeri in pre and post emergence. A randomized block design with four replications was used. The efficacy of herbicides applied in pre emergence was evaluate in two experiments, one in a clayey and other in a sandy soil; 9 herbicide treatments (8 with herbicide application and a control without application) were applied on each soil. Subsequently, two experiments with different... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caruru; Weed control; Resistance; Phenology; Soil texture. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100193 |
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| CASTRO, F. de A.; CAMPOS, I. S.. |
| O controle eficiente e econômico de plantas daninhas é um dos principais fatores de alta produção em todas as culturas. Na cultura da seringueira, não será exagero afirmar que, em sua fase inicial é este o problema técnico mais difícil de resolver, muito especialmente na região Amazônica, onde as condições climáticas favorecem o desenvolvimento de uma flora infestante cuja composição é extraordinariamente variada, exigindo, por conseguinte, um maior número de capinas para manter o cultivo em boas condições de vegetação. Neste trabalho procurou-se estudar o efeito de diferentes doses de misturas de herbicidas, aplicados em pré e pós-emergência, objetivando maior eficiência no controle das plantas daninhas, na cultura da seringueira, nas condiç3es... |
| Tipo: Comunicado Técnico (INFOTECA-E) |
Palavras-chave: Ruber tree; Alto Purus; Acre; Amazônia Ocidental; Western Amazon; Amazonia Occidental; Hevea spp; Control de malezas.; Seringueira; Erva daninha; Defensivo; Herbicida; Caucho.; Herbicides.; Weed control. |
| Ano: 1979 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/492289 |
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| Guareschi,André; Cechin,Joanei; Bianchi,Mario Antonio; Maldaner,Ivan Carlos; Machado,Sergio Luiz de Oliveira. |
| ABSTRACT: Italian ryegrass (Lolium multiflorum Lam.) is a troublesome weed widely found in temperate Brazilian fields with several herbicide-resistant populations. Soil seed bank is the main source of future infestations and can be strongly affected by agricultural practices, such as crop rotation and tillage system. Therefore, this study evaluated the long-term effects of different crop rotation and tillage systems on the seed bank of Italian ryegrass. Data were collected in 2012 and 2013 in a field managed since 1985 under conventional-tillage and no-tillage and subjected to three cropping systems (monoculture, total, and partial rotation) compared to the control plot. The samples were collected at three soil depths (0-5, 5-10, and 10-20 cm) using a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lolium multiflorum Lam.; Dynamic population; Cultural methods; Mechanical practices; Weed control. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162021000500601 |
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| Registros recuperados: 72 | |
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