Arboviruses manipulate rice’s volatile emissions, protecting insect vectors from natural enemies in the field

Abstract

Vector-borne plant viruses depend on insect vectors for transmission and often suppress host defenses that limit vector survival and spread. However, their impact on volatile-mediated indirect defenses remains unclear. Here, we show that rice viruses inhibit methyl salicylate (MeSA) emission, impairing parasitoid recruitment and promoting vector persistence. Field experiments demonstrate that MeSA, a key herbivore-induced volatile, suppresses vector populations by attracting egg parasitoids. Viruses counter this by targeting basic-helix-loop-helix transcription factor OsMYC2, a jasmonic acid signaling hub, thereby down-regulating OsBSMT1 and MeSA biosynthesis, responses conserved across diverse rice viruses and vector species. MeSA applications in the field restore parasitoid-mediated vector suppression, highlighting its potential for sustainable disease control. MeSA is a central ecological signal in a previously unidentified viral strategy that enhances transmission.