Ecology, Environment and Conservation Paper

EFFECT OF TRANSGENIC BT RICE ON NON-TARGET INSECT, BROWN PLANTHOPPER (NILAPARVATA LUGENS) AND ITS SECONDARY EXPOSURE ON THE PREDATORY INSECT MIRID BUG (CYRTORHINUS LIVIDIPENNIS)

Ajit Kumar Mannade, Gajendra Chandrakar, Pankaj Bhargav and Girish Chandel

Abstract

The effect of Bt gene (mcry1Ac) expressing in Swarna transgenic rice plants was assessed on life-history parameters of a non-target insect, brown planthopper (Nilaparvata lugens), and on the predatory insect mirid bug (Cyrtorhinus lividipennis) through secondary exposure. In choice tests carried out on caged rice plants in a containment greenhouse, the egg-laying capacity and hatchability of laid eggs of N. lugens insects on Bt rice and non-Bt rice control plants were similar. A deleterious effect of Bt toxins was not noticed on survival, weight, and development of larvae and nymphs, nor on adult fecundity and egglaying capacity. Our study also indicated no negative effect of Bt proteins on predators and parasites of N. lugens insects by secondary exposure, as the differences in larval survival, developmental period, and male to female ratio of the predator insect C. lividepennis feeding periodically on N. lugens larvae reared on Bt rice and non-Bt rice lines were not significant. No change in growth fitness characteristics was observed among the insects of both species reared on Bt rice and non-Bt rice. Bt toxin at the level expressed in the transgenic rice did not affect the development and reproduction of N. lugens and its predator insect C. lividipennis that fed on brown plant hopper nymphs reared on Bt rice.