Oviposition site preference of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in soybean

Helicoverpa armigera larvae have been attacking several economic important crops all over the world and the estimated costs for the last two harvests were about 620 million dollars in Brazil. The soybean has been consolidated as one of the main Brazilian exportation product and placed within the major commodities of the world. This study was carried out in a commercial soybean crop, in University of São Paulo, Piracicaba, SP. H. armigera eggs distribution were evaluated in plants during soybean development: vegetative and reproductive growth. The results indicated most of the eggs were laid on fully expanded leaves in the superior part of the soybean plant at all growth stages. This distribution resulted from a preference for leaves and the top of the canopy, combined with the dominance of leaves as potential oviposition sites. There was no preference between both sides of the leaf (upper and lower surfaces). It was observed few or no eggs on other structures of the plant, as stems, terminal and growing tips, flowers, and pods. Information about eggs distribution over the plant is not just necessary for sampling techniques development but also for enhancing the integrated management control of this pest. It is discuss emerging dates combination of H. armigera of males and females to obtain eggs in laboratory.