The ovary is the key organ in insect female oviposition. For the continuation of populations in nature, the whole life cycle of female adults is centred on reproduction. Vg and VgR genes are important in determining the synthesis and transport of vitellogenin. Therefore, Vg and VgR gene expression in insect females affects the formation of mature eggs in the ovary, which is very important. RNAi interference of Vg and VgR genes may become an important means to control D. citri populations. A study found that the expression of the DicVg4 and DicVgR genes was significantly affected by DicdsVg4 and DicdsVgR. DicVg4 and DicVgR gene expression interference could prevent the accumulation of vitellogenin in the ovaries of females, rendering ovaries unable to form mature eggs normally and leading to the production of abnormal eggs and nymphs. After knockdown of DicVg4 and DicVgR gene expression, the proportion of ovarian mature eggs was only 8.33 ± 1.67% and 7.75 ± 0.5% in the 10-d developmental stage, the proportion of negative control group ovarian mature eggs was 13.19 ± 0.14% in the 10-d developmental stage, and the proportion of ovarian mature eggs in the interference group was 0.00 ± 0.00% in the 5, 15, 20, 25, and 30-d developmental stages. These results provide a theoretical basis for the use of mixed polygene interference technology to control damage from D. citri populations.

Diaphorina citri, a vector of citrus huanglongbing (HLB) disease, frequently leads to HLB outbreaks and reduces Rutaceae crop production. Recent studies have investigated the effects of RNA interference (RNAi) targeting the Vitellogenin (Vg4) and Vitellogenin receptor (VgR) genes, which are involved in egg formation in this pest, providing a theoretical foundation for developing new strategies to manage D. citri populations. This study presents RNAi methods for Vg4 and VgR gene expression interference and reveals that dsVgR is more effective than dsVg4 against D. citri. We demonstrated that dsVg4 and dsVgR persisted for 3–6 days in Murraya odorifera shoots when delivered via the in-plant system (IPS) and effectively interfered with Vg4 and VgR gene expression. Following Vg4 and VgR gene expression interference, egg length and width in the interference group were significantly smaller than those in the negative control group during the 10–30-day development stages. Additionally, the proportion of mature ovarian eggs in the interference group was significantly lower than that in the negative control group at the 10, 15, 20, 25, and 30-day developmental stages. DsVgR notably suppresses oviposition in D. citri, with fecundity decreasing by 60–70%. These results provide a theoretical basis for controlling D. citri using RNAi to mitigate the spread of HLB disease.