Response of Odorant Receptor LoryOR24 to ( E , E )‐2,4‐Heptadienal and the Effects on the Behavior of the Rice Water Weevil Lissorhoptrus oryzophilus (Coleoptera: Curculionidae)

Abstract BACKGROUND Insect odorant receptors (ORs) play a crucial role in the peripheral olfactory system in detecting odorants. The ORs of Lissorhoptrus oryzophilus (RWW), namely LoryOR7, LoryOR20 and LoryOR27, have been identified, yet only LoryOR20 has been functionally characterized and shown to respond to phenylacetaldehyde (PAA). Most LoryORs remain to be further explored. RESULTS Quantitative real‐time (qRT)‐PCR revealed significant expression of LoryOR24 in the antennae. We used the Xenopus laevis oocyte expression system and two‐electrode voltage clamp (TEVC) technique to express LoryOR24/LoryOrco to detect the effects of rice volatiles, and two rice volatiles were found to be active. As the concentration of ( E , E )‐2,4‐heptadienal gradually increased, the EAG response amplitude of RWWs also increased, peaking at 100 μg μL −1 (8.09 ± 0.61 mV). The behavioral assay confirmed that RWWs exhibited a significant response to 10 μg μL −1 ( E , E )‐2,4‐heptadienal, with an attraction rate of 77.51%. After silencing LoryOR24 via RNAi, RWWs showed significantly reduced electrophysiological and behavioral responses. Furthermore, molecular docking and site‐directed mutagenesis identified that residue F133 is critical for the ligand binding and functional activation of LoryOR24. CONCLUSION The results of our study reveal the molecular basis underlying RWW's recognition of ( E , E )‐2,4‐heptadienal, providing a foundation for the discovery of potential genetic targets at the peripheral olfactory perception level. © 2026 Society of Chemical Industry.