Molecular Mechanism Underlying ROS-Mediated Resistance to Imidacloprid in Whitefly.

Synthetic insecticides used to control include organophosphorus, pyrethroids, insect growth regulators, nicotinoids, and neonicotinoids. Among these, neonicotinoids have been used continuously, which has led to the emergence of high-level resistance to this class of chemical insecticides in the whitefly, making whitefly management difficult. The adipokinetic hormone gene () and reactive oxygen species (ROS) play roles in the development of insect resistance. Therefore, the roles of and ROS in imidacloprid resistance in Mediterranean (MED; formerly biotype Q) were evaluated in this study. The expression level of in resistant MED was significantly lower than that in sensitive (MED) ( < 0.05). expression showed a decreasing trend. After silencing by RNAi, we found that ROS levels as well as the expression levels of the resistance gene and its upstream regulatory factors CREB, ERK, and P38 increased significantly ( < 0.05); additionally, whitefly resistance to imidacloprid increased and mortality decreased ( < 0.001). These results suggest that regulates the expression of resistance genes via ROS in .