Desempenho biológico em função do alimento e sensibilidade a inseticidas em tratamento de sementes de soja da lagarta Helicoverpa armigera

Abstract

H. armigera (Lepidoptera: Noctuidae: Heliothinae) is an extremely polyphagous species, which can cause damage to various crops of economic importance. In soybean, can be both initial pest, attacking cotyledons, shoots and leaves, as, later consume vegetables and seeds. Knowledge of the biological performance of the species in different host plants and the efficiency of seed treatment with insecticides and Bt genotypes are important with a view to the management of this pest, in soybean crop. The objective of this study was to evaluate the influence of food (plant species) consumed by young form in biological attributes of caterpillars and pupae and the potential of insecticides applied in seed treatment and protein Cry 1AC for pest control in soybeans. Four experiments were conducted in climatic chamber (25 ± 2 °C; 60 ± 10% RH, 12 h photoperiod) inentomology laboratory of the Faculdade de Agronomia e Medicina Veterinária, da Universidade de Passo Fundo, Passo Fundo, RS. It was found that food influences on survival, the duration, and the number of instars and consumption of the larval stage of H. armigera. Neonate caterpillars and 3rd- 4th instar caterpillars present, respectively, sensitivity clorantraniliprole insecticide for seed treatment (62,5 mL/100 kg) up to 13 days and 8 days after emergence of soybean plants. Caterpillar of both sizes feature sensitivity to the protein Cry 1Ac at least until 21 days after the emergence of Bt soybean plants