EVIDENCE FOR A MULTICOMPONENT SEX-PHEROMONE IN ERIBORUS-TEREBRANS (GRAVENHORST) (HYM, ICHNEUMONIDAE), A LARVAL PARASITOID OF THE EUROPEAN CORN-BORER

Sex Pheromone activity of Eriborus terebrans (Gravenhorst) (Hymonopter a: Ichneumonidae) was recovered from acetone rinses of flasks that pre viously contained females. The acetone flask rinses elicited the follo wing male responses: upwind anemotaxis, casting, hovering, landing, wi ng-fanning, and mating attempts with other nearby males. Activity of t he acetone flask rinse lasted up to four days on a glass substrate. Po lar component and nonpolar components were demonstrated in the acetone flask rinse. The polar component elicited male behavioral responses s imilar to those by the acetone flask rinse, although retention of male s at the pheromone source and the period of wing-fanning were of short er duration. Chromatography data and chemical derivatization indicated that the polar component had the properties of a carboxylic acid with an additional oxygen-containing functional group. The nonpolar compon ent acted as a synergist since it was inactive alone but increased mal e behavioral responses when added to the polar component. Florisil ope n column chromatography suggested that the nonpolar component was a hy drocarbon(s).