Summer and winter diapause in 'Helicoverpa punctigera': adaptations for a changeable climate

Abstract

Apparent changes in the ecology of 'Helicoverpa punctigera' (Wallengren), including reduced migration from inland Australia and increased proportions of 'H. punctigera' overwintering relative to Helicoverpa armigera (Hübner) in the Namoi Valley have led to concerns about the possibility of Bt (Bollgard II cotton) resistance arising in the future. We have been investigating potential changes in migration and overwintering to determine whether these effects may be reducing the dilution of resistance alleles in the population, and potentially producing a resistant population. In this presentation I will focus on overwintering and diapause.