Abstract

BACKGROUND Symbionts influence the biological and ecological traits of host insects. Regulating the insect–microbe symbiosis represents new strategies for pest control. We previously demonstrated that autophagy induction regulates the abundance of bacteriocyte symbionts in the whitefly Bemisia tabaci MEAM1. RESULTS This study further investigated whether autophagy induction via silencing the Target of Rapamycin (TOR) pathway genes ( LST8 and TOR ) using the plant-mediated gene silencing technology can repress the symbiont abundance and fitness of another invasive whitefly B. tabaci MED. We found that whitefly LST8 and TOR genes can be silenced by virus induced gene silencing approach. LST8 and TOR gene silencing significantly up-regulated the expression of autophagy marker gene Atg8 and led to reduction in the abundance of the symbionts Portiera , Hamiltonella , and Rickettsia in whiteflies. This reduction in symbiont titers led to increased mortality and decreased fecundity in whiteflies. CONCLUSION These findings underscore the potential of manipulating autophagy to disrupt symbiotic abundance as a novel and environmentally friendly strategy for pest management. Our study also suggests that disruption of intracellular symbiosis via insect immunity modulation is feasible for the management of sap-sucking insect pests. © 2026 Society of Chemical Industry.