The Changes in Cross-Resistance, Fitness, and Feeding Behavior in as Their Resistance to Sulfoxaflor Declines.

The increasing resistance in field populations to sulfoxaflor and many different types of insecticides represents a significant challenge in protecting cotton production in China. Although resistant pests were able to regain their susceptibility to insecticides after the reduction in insecticide applications, some of their biological parameters remained different from susceptible strains. The resistance to sulfoxaflor was unstable in after the loss of selective pressure.

Reduced expression of the P-glycoprotein gene HaABCB1 is linked to resistance to Bacillus thuringiensis Cry1Ac toxin but not Cry2Ab toxin in Helicoverpa armigera.

Rapid evolution of pest resistance to Bt insecticidal proteins presents a serious threat to the sustainable use of Bt crops. The cotton bollworm has been extensively exposed to Bt cotton worldwide and has evolved resistance in laboratory and field. Previous studies have highlighted the significant roles played by the ABC transporter proteins in Bt resistance.

Cadherin Is a Binding Protein but Not a Functional Receptor of Bacillus thuringiensis Cry2Ab in Helicoverpa armigera.

Midgut receptors play a critical role in the specificity of Cry toxins for individual insect species. Cadherin proteins are essential putative receptors of Cry1A toxins in lepidopteran larvae. Cry2A family members share common binding sites in Helicoverpa armigera, and one of them, Cry2Aa, has been widely reported to interact with midgut cadherin.