Eficiência do inseticida clorpirifós no controle de larvas de Diabrotica speciosa (Germ.) (Coleoptera:Chrysomelidae) na cultura da batata

Abstract

Foi avaliado o desempenho do inseticida clorpirifós no controle de larvas de Diabrotica speciosa (Germ.) (Coleoptera: Chrysomelidae), na cultura da batata. O experimento foi desenvolvido na safra de primavera, quando ocorre maior incidência de insetos pragas e, conseqüentemente, danos nos tubérculos de batata no Rio Grande do Sul. As diferentes dosagens e formulações dos inseticidas foram aplicadas no sulco de plantio, utilizando-se clorpirifós (2, 3 e 4 l i.a./ha de Lorsban 480 CE e 2 e 3kg i.a./ha de Lorsban 10 G) e como padrão, forate (2kg i.a./ha de Granutox 50G). Os melhores controles ocorreram nos tratamentos com Granutox 50G, na dosagem de 2kg i.a./ha; seguido por Lorsban 10 G, 3 e 2kg i.a./ha e Lorsban 480 CE, 4 e 3l i.a./ha.A field trial was conducted to evaluate the performance of the insecticide chlorpyrifos in two formulations, emulsifiable and granular, for the control of Diabrotica speciosa (Germ.) (Coleoptera:Chrysomelidae) in potato. The field trial was conducted during the spring season when incidence of insect pests and, consequently, damage are high in Rio Grande do Sul state, Brazil. The different dosages and formulations of insecticides were applied in the planting furrow utilizing chlorpyrifos (2, 3 and 4l i.a./ha of Lorsban 480 CE and 2 and 3kg i.a./ha de Lorsban 10G) and the standard phorate (2kg i.a./ha of Granutox 50G). Best field control performances were obtained with Granutox 50G, in the dosage of 2kg i.a./ha; Lorsban 10G, 3 and 2kg i.a./ha, followed by Lorsban 480 CE, 4 and 3l i.a./ha.