Male-emitted benzaldehyde acts as an olfactory antagonist, disrupting moth sex pheromone communication

moths emit benzaldehyde (BA) during courtship competition to disrupt rivals' ability to detect the female sex pheromone (Z)-11-hexadecenal (Z11-16:Ald). BA release is socially regulated and increases markedly under high male density and in the presence of female-derived cues or synthetic Z11-16:Ald. Electrophysiological recordings and calcium imaging assays indicate that BA suppresses peripheral olfactory responses by competitively inhibiting the Z11-16:Ald-specific receptor MsepPR3 at the ligand-binding site, as confirmed through structural modeling and dynamics simulations. This receptor-level antagonism represents a mechanism of olfactory disruption during reproductive competition. Our findings reveal a context-dependent strategy through which male moths disrupt rival chemosensory perception, providing insight into the evolution of sexual signaling and suggesting receptor-targeted approaches for future pest management applications.