Abstract

Chilo suppressalisis one of the most damaging rice pests in China’s rice-growing regions. Chemical pesticides are the primary method for pest control; the excessive use of insecticides has resulted in pesticide resistance.C. suppressalisis highly susceptible to cyproflanilide, a novel pesticide with high efficacy. However, the acute toxicity and detoxification mechanisms remain unclear. We carried out a bioassay experiment withC. suppressalislarvae and found that the LD10, LD30and LD50of cyproflanilide for 3rd instar larvae was 1.7 ng/per larvae, 6.62 ng/per larvae and 16.92 ng/per larvae, respectively. Moreover, our field trial results showed that cyproflanilide had a 91.24% control efficiency againstC. suppressalis. We investigated the effect of cyproflanilide (LD30) treatment on the transcriptome profiles ofC. suppressalislarvae and found that 483 genes were up-regulated and 305 genes were down-regulated in response to cyproflanilide exposure, with significantly higherCYP4G90andCYP4AU10expression in the treatment group. The RNA interference knockdown ofCYP4G90andCYP4AU10increased mortality by 20% and 18%, respectively, compared to the control. Our results indicate that cyproflanilide has effective insecticidal toxicological activity, and that theCYP4G90andCYP4AU10genes are involved in detoxification metabolism. These findings provide an insight into the toxicological basis of cyproflanilide and the means to develop efficient resistance management tools forC. suppressalis.Keywords:Chilo suppressalis;cyproflanilide;P450;RNA interference