Gypsy Moth Kairomones Influencing Behavior of the Parasitoids Brachymeria intermedia and Apanteles melanoscelus

Gypsy moth kairomones influencing host recognition responses of two species of hymenopteran parasitoids, the chalcicid Brachymeria intermedia (Nees) and the braconid Apanteles melanoscelus (Ratz.) were recovered from the gypsy moth, Porthetria dispar L. A kairomone for B. intermedia was removed by washing gypsy moth pupae with hexane. The pupal wash, when exposed on filter paper to B. intermedia females, elicited an antennal response characteristic of adults when they find host pupae. A kairomone for A. melanoscelus was obtained by washing gypsy moth larvae with hexane. For A. melanoscelus , antennal responses were recorded with hexane washes of gypsy moth larvae, but not of pupae, and for B. intermedia , responses occurred with hexane washes of pupae, but not of larvae. Work on identification of the kairomones is in progress.