Function Analysis of P450 and GST Genes to Imidacloprid in (Koch).

(Koch) is an economically important pest that affects legumes in worldwide. Chemical control is still the primary efficient method for management. However, the mechanism underlying insecticide resistance in has not been elucidated. A previous study observed that piperonyl butoxide (PBO) and diethyl maleate (DEM) significantly synergized imidacloprid in field populations, indicating that cytochrome P450 (P450) and glutathione S-transferase (GST) genes may play pivotal roles in imidacloprid resistance. In this study, 38 P450 genes and 10 GST genes were identified in through transcriptomic analysis. The expression levels of these P450 and GST genes were measured in susceptible (SUS) strains of under imidacloprid treatment with LC, LC, and LC doses. The expression levels of , , , , , , and were up-regulated in the three treatments. Most of these genes belong to CYP3 and CYP4 Clans. In addition, the expression levels of all P450 and GST genes in were also measured in the Juye (JY) and Linqing (LQ) field populations. The expression levels of , , and were up-regulated in the SUS strain after imidacloprid treatment at three doses, and these genes were overexpressed in the JY population. Furthermore, the sensitivity of to imidacloprid was significantly increased after knockdown of and through RNA interference. These results may help to elucidate the mechanisms underlying of imidacloprid resistance in .