Crop Biotech Update

Inheritance of Resistance to Cry1Ac Toxin in Cotton Bollworm from India

May 20, 2011

Cotton bollworm (Helicoverpa armigera) is one of the notorious pests of cotton. Through the years, the pest has developed resistance to most groups of chemical insecticides. This led to the adoption of Bt cotton. However, resistance to Bt toxins may still develop in insect populations. Thus, Paramjit Kaur and colleagues at Punjab Agricultural University, India, conducted a study to investigate the genetic basis of resistance to effectively develop and implement strategies on delaying resistance.

The researchers confirmed the mode of inheritance of resistance through bioassay response of resistant (BM-R), susceptible (HP-S) heterozygotes and backcross progeny to Cry1Ac incorporated in semi-synthetic diet. Based on dominance, degree of dominance and backcross values, resistance could be polygenic, autosomal, and inherited as a recessive trait.

The abstract is available at