Avaliação da eficácia de diferentes inseticidas no controle da mosca-branca Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) Biótipo B em plantas de soja Glycine max (L.) Merrill.

Abstract

Due to the great reproductive potential of the whitefly Bemisia tabaci biotype B (Hemiptera: Aleyrodidae), absence of alternative methods for large-scale crops, makes chemical control the main tool used for the management of this pest. Thus, the effect of different insecticides on eggs and adults of whitefly in the soybean crop was evaluated under greenhouse conditions. The objective of this work was to evaluate the effect of different insecticides on adults and eggs whitefly in soybean crop. Two experiments were carried out in a greenhouse conditions at the Laboratory of Applied Entomology of the Universidade Federal Grande Dourados (UFGD). The insecticides used were Oberon 240 SC, Benevia 100 OD, Vertimec 18 CE e Polo 500 SC. The first trial was conducted to evaluate the effect of insecticides about eggs. Being that the application of the treatments occurred after the artificial infestation of the whitefly and the previous count of the eggs. The evaluations were done 1, 4 and 7 days after the application of the treatments. In the second experiment the pots containing the soybean plants were placed in cages with a plastic tube frame and anti-aphid screen, posteriorly 100 adults were released from whitefly collected in the breeding house. After 1 hour of the release of the adults, were treatments made the applied. And the evaluations were performed 1, 8 and 24 hours after the application of the treatments. In both experiments the soybean growcrops used was M6419 IPRO®. The experimental design used was a randomized block with 5 treatments and 5 replicates. The results showed that none of the tested insecticides obtained satisfactory control above 80% in both experiments, being that cyantraniliprole 75 g. ha-1 and abamectin 10.8 g. ha-1 were the most efficient, presenting 12.86 and 17.57% of control, respectively, 7 days after application of the treatments and for the experiment with adults, the same insecticides provided greater control, corresponding to 46.80 and 40.21%, respectively, 24 hours after application of the treatments.