Study on the interference of DicdsVg4 and DicdsVgR in egg formation in the ovary of Diaphorina citri (Kuwayama)

ABSTRACT 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.