(-)-Germacrene D receptor neurones in three species of heliothine moths: structure-activity relationships

J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2003 Jul;189(7):563-77. doi: 10.1007/s00359-003-0434-y. Epub 2003 Jun 25.


Specificity of olfactory receptor neurones plays an important role in food and host preferences of a species, and may have become conserved or changed in the evolution of polyphagy and oligophagy. We have identified a major type of plant odour receptor neurones responding to the sesquiterpene germacrene D in three species of heliothine moths, the polyphagous Heliothis virescens and Helicoverpa armigera and the oligophagous Helicoverpa assulta. The neurones respond with high sensitivity and selectivity to (-)-germacrene D, as demonstrated by screening via gas chromatography with numerous mixtures of plant volatiles. Germacrene D was present in both host and non-host plants, but only in half of the tested species. The specificity of the neurones was similar in the three species, as shown by the "secondary" responses to a few other sesquiterpenes. The effect of (-)-germacrene D was about ten times stronger than that of the (+)-enantiomer, which again was about ten times stronger than that of (-)-alpha-ylangene. Weaker effects were obtained for (+)-beta-ylangene, (+)-alpha-copaene, beta-copaene and two unidentified sesquiterpenes. The structure-activity relationship shows that the important properties of (-)-germacrene D in activating the neurones are the ten-membered ring system and the three double bonds acting as electron-rich centres, in addition to the direction of the isopropyl-group responsible for the different effects of the germacrene D enantiomers.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / drug effects
  • Animals
  • Dose-Response Relationship, Drug
  • Electrophysiology / methods
  • Feeding Behavior / drug effects*
  • Feeding Behavior / physiology
  • Female
  • Moths / chemistry
  • Neurons / drug effects*
  • Neurons / physiology
  • Olfactory Pathways / drug effects
  • Olfactory Pathways / physiology
  • Olfactory Receptor Neurons / metabolism*
  • Plants / chemistry
  • Sense Organs / anatomy & histology
  • Sense Organs / drug effects
  • Sesquiterpenes / chemistry
  • Sesquiterpenes / pharmacology*
  • Sesquiterpenes, Germacrane*
  • Species Specificity
  • Stereoisomerism
  • Stimulation, Chemical
  • Structure-Activity Relationship


  • Sesquiterpenes
  • Sesquiterpenes, Germacrane
  • germacrene D