The venom‐specific toxicity profiles of the mirid bug <i>Tytthus chinensis</i> to its prey insect <i>Nilaparvata lugens</i>

BACKGROUND: Tytthus chinensis, a predatory mirid, is an effective natural enemy in rice ecosystems. Although this species utilizes venomous saliva to immobilize and digest prey, the functional specialization and insecticidal mechanisms of its salivary gland venom remain unclear. RESULTS: In this study, we characterized the anatomy of the venom apparatus and evaluated the toxicity of its distinct salivary glands. The venom system comprises an anterior main gland (AMG), a posterior main gland (PMG) and an accessory gland (AG). Bioassays using venom extracted from each gland demonstrated that AG venom exhibited the highest toxicity, significantly reducing insect survival and eclosion rates, and also severely impairing sperm production and fecundity. AG venom elicited marked oxidative stress in insects, as evidenced by elevated antioxidant enzyme activities, increased lipid peroxidation, and decreased glutathione levels. Quantitative (q)PCR results further confirmed the high enrichment of toxin-related genes in AG, such as venom-like allergen 5, serine protease inhibitors and ω-toxin-like. By contrast, plant-defense related genes were highly expressed in AMG and PMG tissue. CONCLUSIONS: Our findings demonstrate a clear functional specialization among the salivary glands of T. chinensis and identify AG venom as a critical factor mediating prey paralysis, oxidative damage and reproductive suppression. This work provides a foundation for developing novel bio-insecticides derived from predator venom components. © 2026 Society of Chemical Industry.