Impact of Bt cotton on the population dynamics of the cotton aphid in greenhouse

Abstract

The objective of this work was to develop an experimental protocol to assess the impact of Bt cotton on bionomics and on plant choice for Aphis gossypii colonization. The bionomics of the cotton
aphid was assessed in greenhouse with insects reared in individual cages containing Bt cotton plants of the variety DP 404 BG (Bollgard) or its nontransformed isoline DP 4049. Cages with Bt cotton and non-Bt cotton
were used as choosing arena for evaluation of winged adults preference. There was no signifi cant difference for pre-reproduction period (immature phase), reproduction period, longevity, survivorship curve total and daily production of offspring by female, and curve of accumulated production of offspring by the population.
There was no preference of colonization for any plant by winged adults, which indicates equivalent rates of colonization of the initial populations. Bt cotton plants do not affect the population dynamics of A. gossypii,
and do not increase its potential risk as pest.