Resistance toward Triflumezopyrim Related to Overexpression of <i>SfUGT35A1</i> and <i>SfGSTd2</i> in <i>Sogatella furcifera</i> (Hemiptera: Delphacidae)

<i>Sogatella furcifera</i> is a migratory pest that harms rice cultivation. Triflumezopyrim (TFM), a novel insecticide, effectively controls <i>S. furcifera</i>. To guide its scientific application, we studied the TFM resistance mechanisms in resistant strains. Through cross-resistance determination, we found that the strain had cross-resistance to clothianidin. Synergistic and enzyme activities also demonstrated that the TFM resistance was related to the enhancement of glutathione <i>S</i>-transferases and UDP-glycosyltransferases. Meanwhile, <i>SfGSTd2</i>, <i>SfUGT2,</i> and <i>SfUGT35A1</i> were invariably upregulated in the TFM-resistant strain. RNAi revealed that <i>SfGSTd2</i> (mortality increasing 33.3-53.3%) and <i>SfUGT35A1</i> (increasing 33.3-46.7%) significantly increased sensitivity on TFM, while <i>SfUGT35A1</i> (increasing 40.0-46.7%) also clearly promoted sensitivity toward clothianidin in <i>S. furcifera</i>. The GAL4/UAS system further verified that the overexpression of <i>SfUGT35A1</i> is involved in the formation of TFM (mortality descending 2.8-52.8%) and clothianidin resistance (mortality descending 11.1-41.7%). Therefore, all results showed that the overexpression of <i>SfGSTd2-</i> and <i>SfUGT35A1-</i>mediated resistance to TFM in <i>S. furcifera</i>.