Residual de metribuzin no solo sobre o crescimento do alho, cebola e feijão

Abstract

Metribuzin is an herbicide widely used in the control of weeds in crops such as soybean, potato and tomato. However, there is suspicion of intoxication in crops cultivated in succession due to the residual effect of the product in the soil. As such, our goal was to evaluate the residual effect of metribuzin in the soil on the growth of garlic, onion and beans plants. Three experiments were conducted in a greenhouse, in a randomized block design, with four replications. Each experiment corresponded to the evaluated crop: garlic, onion or beans. The treatments consisted of different metribuzin concentrations in the soil (0; 6; 12; 24; 48; 96; 144; 192; 240 and 480 ppb). Visual intoxication was evaluated at 7, 14, 21 and 28 days after emergence (DAE) of the crops and dry matter at 28 DAE. Intoxication was identified in the garlic and bean plants at metribuzin concentration of 96 ppb, with maximum impact of 55 and 63%, respectively, at 28 DAE. In the onion crop, symptoms of intoxication arose at 40 ppb, and from 14 DAE onwards, plant death was noted at herbicide concentrations from 240 to 480 ppb. The dry matter of the bean and onion plants was reduced by the presence of herbicide in the soil, while garlic plant growth was not affected. Residues of metribuzin in the soil can hinder successive planting of garlic, onion or bean crops. It was concluded that garlic, onion and bean plants are sensitive to the residual effect of metribuzin in the soil.Resumo -O metribuzin é um herbicida amplamente utilizado para o controle de plantas daninhas em culturas como a soja, a batata e o tomate. No entanto, há suspeitas de intoxicações de culturas cultivadas em sucessão devido a resíduos desse produto no solo. Assim, objetivou-se avaliar o efeito de resíduos de metribuzin no solo sobre o crescimento de plantas de alho, cebola e feijão. Foram realizados três experimentos em casa de vegetação, no delineamento de blocos casualizados, 1

Residual effect of pre-emergent herbicides on the initial development and biochemical composition of snap bean seedlings

“…However, regardless of the product and cultivar tested, it was evident that the pre-emergent action reduces the accumulation of dry matter due its performance in the physiological metabolism of seedling growth, either by the influence on the protein metabolic pathway or by the reduction of the assimilation capacity of nutrients. Walperes et al (2015) studying the action of pre-emergent herbicides, in this case metribuzin, also observed reduction at the dry mass of beans after pre-emergent herbicides, which proves the potential damage of this class of herbicides.…”

Atividade residual de herbicidas nas culturas do milho e da soja

“…Esta molécula possui meia-vida entre 11,5 a 19 dias, de acordo com as características físico-químicas do solo (PPDB, 2018), e apresenta baixa adsorção no solo, sendo facilmente lixiviável (Silva Júnior et al, 2015). Walperes et al (2015), estudando o efeito residual de doses crescentes de Metribuzin no solo, constataram que seus resíduos podem inviabilizar a sucessão de culturas com alho, cebola e feijão.…”