In Plant system-mediated double-stranded RNA delivery targeting Laccase 2 and Tyrosine 3-monooxygenase genes disrupt Diaphorina citri development

Abstract

Diaphorina citri is the primary vector of Candidatus Liberibacter asiaticus (CLas), the causal agent of Huanglongbing (HLB), a devastating citrus disease with global economic and agricultural impact. Current management strategies rely heavily on insecticides, which, when misused, pose environmental risks, harm nontarget organisms, and promote insecticide resistance. RNA interference (RNAi) has emerged as a promising, species-specific, and environmentally sustainable alternative for D. citri control by targeting essential genes. This study investigated the effects of silencing Laccase 2 and Tyrosine 3-monooxygenase, key melanization-related genes in D. citri, via oral delivery of double-stranded RNA (dsRNA) applied to Murraya paniculata branches. Gene silencing increased mortality, delayed development, and reduced significantly the adult emergence, demonstrating the essential roles of these genes in D. citri survival. Moreover, dsRNA remained stable in M. paniculata leaves for up to 144 h, highlighting the feasibility of this delivery method for prolonged gene silencing. These findings support RNAi as a viable, environmentally friendly strategy for managing D. citri populations, disrupting nymphal development, and limiting CLas transmission, offering a sustainable approach for mitigating HLB in citrus production.