Dessecação de Crotalaria juncea no outono

Abstract

Dessecação de Crotalaria juncea no outono RESUMOObjetivou-se com este trabalho avaliar a ação do glyphosate em aplicação isolada e em misturas com 2,4-D ou metsulfuron methyl, na dessecação de plantas adultas de Crotalaria juncea no outono, em área de plantio. Foram instalados dois experimentos, sendo utilizado o delineamento experimental em blocos ao acaso, num esquema fatorial 4 x 3, com quatro repetições. Os tratamentos estudados no primeiro ensaio foram: quatro doses (0,00; 0,54; 1,08 e 1,62 kg ha -1 ) de glyphosate, associadas a três (0,00; 0,806 e 1,209 kg ha -1 ) de 2,4-D. No segundo ensaio foram estudadas as mesmas doses do glyphosate, associadas a três (0,0; 4,0 e 8,0 g ha -1 ) de metsulfuron-methyl. Foram realizadas avaliações visuais de fitointoxicação, contagem do número de plantas com rebrota e matéria seca de plantas. Concluiu-se que o glyphosate, em aplicação isolada ou em associações com o 2,4-D ou metsulfuron-methyl, independentemente das doses utilizadas, foi ineficaz na dessecação de plantas adultas de Crotalaria juncea. Palavras-chave:Adubo verde, controle de plantas daninhas, herbicida. Desiccation of Crotalaria juncea in the autumn season ABSTRACTThe objective of this study was to evaluate the effect of glyphosate applied alone and in mixtures with 2.4-D or metsulfuron methyl in the desiccation of mature plants of Crotalaria juncea during the fall season, in a field crop. Two experiments were carried out using a randomized experimental block design, in a 4 x 3 factorial scheme, with four replications. Treatments in the first experiment were formed by four doses (0.00, 0.54, 1.08 and 1.62 kg ha -1 ) of glyphosate, associated with three doses (0.00, 0.806 and 1.209 kg ha -1 ) of 2 ,4-D. In the second experiment the same doses of glyphosate were studied associated with three doses (0.0 4.0 and 8.0 g ha -1 ) of metsulfuron-methyl. Visual evaluations of plant poisoning, score number of plants with regrowth and dry matter of plants were determined. It was concluded that glyphosate applied alone or in association with 2.4-D or metsulfuron-methyl, regardless of the applied doses, was ineffective in the desiccation of mature plants of Crotalaria juncea.

Differential tolerance of crotalaria species to herbicides

“…Adult plants of C. juncea were susceptible to the association of glyphosate with paraquat (Torres et al, 2008). In another study, glyphosate in isolated application or in association with 2,4-D or metsulfuron-methyl, permitted regrowth when applied in adult plants of C. juncea (Espanhol et al, 2011).…”