Inhibition of ecdysone receptor (DcEcR) and ultraspiracle (DcUSP) expression in Diaphorina citri increased susceptibility to pesticides.

Diaphorina citri Kuwayama is of great concern because of its ability to transmit devastating citrus greening illness (Huanglongbing). One strategy for controlling HLB may involve limiting the spread of D. citri. Insecticides using dsRNA target genes may be a useful option to control D. citri. The ecdysone receptor (EcR) and ultraspiracle (USP) are crucial for the growth and reproduction of insects. This study identified the genes for D. citri ecdysone receptor (DcEcR) and ultraspiracle (DcUSP). According to the qPCR data, DcUSP peaked at the 5th-instar nymph stage, while DcEcR peaked at the adult stage. Females expressed DcEcR and DcUSP at much higher levels than males. RNAi was used to examine DcEcR and DcUSP function. The findings demonstrated that inhibition of DcEcR and DcUSP delayed nymph development and decreased survival and eclosion rates. dsEcR caused adults to develop deformed wings, and dsUSP caused nymphs to wither and die. Female adult ovaries developed slowly, and the females laid fewer eggs. Additionally, DcEcR and DcUSP were inhibited, increasing D. citri susceptibility to pesticides. These findings suggest that DcEcR and DcUSP are critical for D. citri development, growth, and reproduction and may serve as potential targets for D. citri management.