title: Changes in odor background affect the locomotory response to pheromone in moths.
abstract: Many animals rely on chemical cues to recognize and locate a resource, and they must extract the relevant information from a complex and changing odor environment. For example, in moths, finding a mate is mediated by a sex pheromone, which is detected in a rich environment of volatile plant compounds. Here, we investigated the effects of a volatile plant background on the walking response of male Spodoptera littoralis to the female pheromone. Males were stimulated by combining pheromone with one of three plant compounds, and their walking paths were recorded with a locomotion compensator and analyzed. We found that the addition of certain volatile plant compounds disturbed the orientation toward the sex pheromone. The effect on locomotion was correlated with the capacity of the plant compound to antagonize pheromone detection by olfactory receptor neurons, suggesting a masking effect of the background over the pheromone signal. Moths were more sensitive to changes in background compared to a constant background, suggesting that a background odor also acts as a distracting stimulus. Our experiments show that the effects of odorant background on insect responses to chemical signals are complex and cannot be explained by a single mechanism.
authors.affiliation: UMR 1272 Physiologie de l'Insecte Signalisation et Communication, INRA, Versailles, France. vparty@live.fr
authors.forename: Virginie
authors.initials: V
authors.lastname: Party
authors.forename: Christophe
authors.initials: C
authors.lastname: Hanot
authors.forename: Daniela Schmidt
authors.initials: DS
authors.lastname: Büsser
authors.forename: Didier
authors.initials: D
authors.lastname: Rochat
authors.forename: Michel
authors.initials: M
authors.lastname: Renou
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D004594:Electrophysiology; D005260:Female; D008124:Locomotion / Q000187:drug effects; D008297:Male; D009068:Movement; D009812:Odorants; D018034:Olfactory Receptor Neurons / Q000187:drug effects / Q000502:physiology; D010675:Pheromones / Q000378:metabolism*; D012724:Sex Attractants / Q000378:metabolism*; D012726:Sexual Behavior, Animal; D012903:Smell / Q000502:physiology*; D018411:Spodoptera / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D055549:Volatile Organic Compounds / Q000737:chemistry
chemical_list: D010675:Pheromones; D012724:Sex Attractants; D055549:Volatile Organic Compounds