Editing Plant Volatile Isoeugenol for Integrated Aphid Management: Discovering Ecofriendly Insect Behavioral...

Chemical ecology-based insect behavioral regulation approaches, particularly the "push-pull" strategy, hold tremendous potential for sustainable pest management. Odorant-binding proteins (OBPs) are key targets for regulating insect behavior, whereas plant volatile organic compounds function as key semiochemicals. A series of isoeugenol derivatives were rationally edited by targeting Acyrthosiphon pisum OBP9 and Harmonia axyridis OBP15 for discovering botanical-based insect behavioral regulators. Most derivatives demonstrated significantly higher target binding activity than isoeugenol, with compound I-10 showing exceptional bioactivity. I-10 displayed excellent A. pisum-repellent and H. axyridis-attractive activities. Molecular mechanism studies established the superior binding ability of I-10 to both OBPs via hydrophobic interactions, with its high chemical softness, large hydrophobic surface area, and extensive charge distribution contributing to its bioactivity. Importantly, I-10 showed favorable biosafety for honeybees, ladybugs, parasitic wasps, and plants. This study provides novel insights for developing ecofriendly candidates with push-pull activity by targeting OBPs for integrated aphid management.