9600094 Feeny This project combines the approaches of systematics and chemical ecology to investigate the factors controlling the number of host species attacked by wasps of the genus Trogus (family Ichneumonidae), all species of which parasitize caterpillars of the butterfly family Papilionidae. The systematics of Trogus and related genera will be investigated to identify trends in the evolution of host associations. To identify mechanisms of host-finding, behavioral experiments will be conducted with the North American species Trogus pennator. By comparing the chemical compounds used to locate host caterpillars on different food plants, this research will test the hypothesis that taxonomic restriction in host range results from conservative responses to chemical cues shared by these plants. Parasitic wasps are the single most important natural enemy of crop pests. Better understanding of their biology may suggest new ways to manipulate parasitoids and agroecosytems for improved pest control and reduced use of insecticides.
