Laboratory evaluation of effects of transgenic Bt corn pollen on two non-target herbivorous beetles, Epilachna vigintioctopunctata (Coccinellidae) and Galerucella vittaticollis (Chrysomelidae)

Abstract

Laboratory bioassays were conducted to evaluate the effect of pollens from insecticidal transgenic Bt corn (event MON863) expressing Cry3Bb1 endotoxin on two native non-target herbivorous beetles, Epilachna vigintioctopunctata (Coccinellidae) and Galerucella vittaticollis (Chrysomelidae) larvae. Larvae were reared on leaf discs exposed to corn pollen for 10 days after hatching. G. vittaticollis had no adverse performance in terms of larval survival and development (proportion of larvae to third instar) between pollen doses of 500 and 2,000 grains/cm2. Similarly, E. vigintioctopunctata did not show significant deleterious effects between pollen doses of 250 and 2,000 grains/cm2. From the actual pollen doses deposited on leaf surfaces near cornfields, it was concluded that corn pollen from MON863 has no adverse effects on E. vigintioctopunctata and G. vittaticollis populations living on wild plants near cornfields.