Digestive enzyme-encoding genes regulate the adaptability of <i>Frankliniella occidentalis</i> to the defense responses of kidney bean plants

Frankliniella occidentalis (Western flower thrips; WFT) is an important pest of vegetable and flower crops. The development and application of plant-induced resistance and RNA interference (RNAi) technology are environmentally sustainable and promising approaches in pest control research. This study verified the regulatory role of digestive enzyme genes in the adaptation of WFT to jasmonic acid (JA)-induced defense responses in Phaseolus vulgaris (kidney bean) plants. First, 4 digestive enzyme-encoding genes were cloned and identified. Subsequently, their expression patterns during different developmental stages were analyzed. Second, the mRNA levels of these genes were analyzed in the F0 and F1 generation female adult WFT that fed on leaves from JA-induced bean plants. The results showed that the expression of FoαAmy1 (α-amylase gene) and FoEG1 (endoglucanase gene) was significantly upregulated during the adaptation of WFT to the JA-induced defense response in kidney bean plants. RNAi and bioassay results indicated that silencing FoαAmy1 and FoEG1 significantly reduced the survival rate and feeding damage caused by adult WFT that fed on JA-induced kidney bean plants. Overall, FoαAmy1 and FoEG1 may be involved in regulating the adaptability of WFT to JA-induced defense responses in kidney bean plants.