Host plant volatiles synergize responses of sex pheromone-specific olfactory receptor neurons in male Helicoverpa zea.
Single-cell electrophysiological recordings were obtained from olfactory receptor neurons in antennal trichoid sensilla of male corn earworm, Helicoverpa zea. Spontaneous activity of the neuron specific for the major component ( Z)-11-hexadecenal, the conspecific female-emitted sex pheromone, was not affected by exposure to host plant volatiles. However, stimulations with binary mixtures of a threshold dosage of the pheromone component and increasing dosages of either linalool or ( Z)-3-hexenol significantly synergized the pheromone-specific neuron's firing rates compared with responses to the major pheromone component alone. Cross-adaptation studies confirmed that the enhanced impulses originated from the pheromone-component-tuned neuron. Because plant volatiles do not stimulate the pheromone-specific neuron when presented alone, the pheromone plus host odor blend would be interpreted as containing more pheromone than it actually does when processed by the pheromone-processing portion of the antennal lobe.
Ochieng
S A
SA
Department of Entomology, Iowa State University, Ames, IA 50011, USA. sochieng@iastate.edu
Park
K C
KC
Baker
T C
TC
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000819:Animal Communication; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004594:Electrophysiology / Q000379:methods; D005260:Female; D008297:Male; D009036:Moths / Q000187:drug effects / Q000502:physiology*; D009812:Odorants; D018034:Olfactory Receptor Neurons / Q000187:drug effects / Q000502:physiology*; D010675:Pheromones / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D012724:Sex Attractants / Q000494:pharmacology; D014835:Volatilization
D010675:Pheromones; D010936:Plant Extracts; D012724:Sex Attractants