Abstract
BACKGROUND
The Asian citrus psyllid,
Diaphorina citri
, vectors
Candidatus
Liberibacter asiaticus (
C
Las) that causes citrus greening disease, which has devastated global citrus production. Current management primarily relies on the application of synthetic chemical insecticides, resulting in the evolution of resistance among
D
.
citri
populations.
C
Las is ingested by
D
.
citri
while feeding on infected plants and subsequently interacts with the gut epithelial surface to establish infection. To determine the functional significance of abundant gut surface proteins in
D. citri
during
C
Las uptake, we used RNA interference (RNAi) to silence nine key gut surface protein genes.
RESULTS
Following membrane feeding on double‐stranded RNAs (dsRNAs), transcript levels were reduced by 20–51% in adults and 28–50% in nymphs at 72 h, with higher knockdown efficiencies of 41–63% in adults and 30–81% in nymphs by 120 h. Some dsRNA treatments increased
D. citri
mortality by approximately 20% over the control treatment, and two treatments reduced honeydew production indicative of reduced feeding consistent with disrupted gut function. Silencing of several individual proteins, including alkaline phosphatase, cadherin, cluster of calcium‐transporting ATPase, croquemort and monocarboxylate transporter, reduced
C
Las uptake in nymphs and/or adults.
CONCLUSION
Silencing of abundant gut surface proteins in
D. citri
limited
C
Las uptake, establishing a functional basis for RNAi‐mediated suppression of pathogen uptake. While additional studies are needed to determine specific molecular interactions, these results identify gut surface proteins as promising targets for RNAi‐based interventions to reduce
C
Las uptake by psyllids. © 2026 Society of Chemical Industry.