Targeted disruption of vacuolar‐sorting protein and inhibitor of apoptosis genes via virus‐induced gene silencing alters survival and reproduction of Diaphorina citri

BACKGROUND: Citrus production worldwide is severely impacted by a devastating disease known as citrus greening, or Huanglongbing (HLB). The phytopathogen causing HLB is transmitted between trees by the Asian citrus psyllid, Diaphorina citri, which acts as the primary vector. Currently, there is no cure for HLB, and management efforts primarily rely on the use of insecticides. However, there is a growing need for alternative, environmentally sustainable control methods, such as RNA interference (RNAi). RESULTS: We investigated the impact of gene silencing on the mortality of D. citri by targeting two genes, vacuolar-sorting protein/sucrose non-fermenting protein 7 (DcSnf7) and inhibitor of apoptosis 5 (DcIap5). Gene silencing was initially assessed by delivering synthesized double-stranded RNA (dsRNA) to D. citri through topical feeding. To further assess gene suppression in vivo, we used a virus-induced gene silencing (VIGS) approach to deliver RNAi to psyllids via citrus plants. Suppressing DcSnf7 and DcIap5 individually resulted in elevated nymph mortality; however, the combined suppression of both genes using dual dsRNA treatment did not yield an additive effect. We modified the infectious Citrus tristeza virus (CTV-T36) clone to individually and jointly carry the truncated genes, DcSnf7 and DcIap5. Over two successive generations, D. citri reared on plants inoculated with CTV-tSnf7, CTV-tIap5, or the combined construct CTV-tSnf7-tIap5 exhibited increased mortality at all life stages, as well as significantly reduced fecundity and fertility, compared to insects reared on non-infected or CTV-wt-inoculated control plants. In addition, these VIGS plants shortened the lifespan of D. citri. Notably, the dual construct CTV-tSnf7-tIap5 consistently produced the most pronounced reductions in survival, fecundity, fertility, and longevity of D. citri across all experiments, exceeding the effects observed with either single-gene construct. CONCLUSIONS: Our results suggest that silencing key genes of D. citri using RNAi mediated by VIGS represents a promising control strategy that could play a role in HLB management. © 2026 Society of Chemical Industry.