Flight Response ofHabrobracon hebetor(Say) (Hymenoptera: Braconidae) in a Wind Tunnel to Volatiles Associated with Infestations ofEphestia kuehniellaZELLER (Lepidoptera: Pyralidae)

Mated, host experiencedHabrobracon hebetor(Say) females were found to fly in a wind tunnel to frass from their host,Ephestia kuehniellaZeller. Distance from the odor source, light intensity, and wind speed were found to influence the flight response. Although differences were found in the flight response of 1- to 13-day-old mated, host experienced females to host frass, they were not significant. Naive virgin females did not respond to host frass in the wind tunnel, while naive mated females did. Experience with hosts, particularly stinging and ovipositing, resulted in a significant increase in the response to host frass of both virgin and mated females, although preexposure to frass or host larval contact were much less effective in eliciting flight behavior. Separation of the active components in host frass resulted in the isolation of two fractions that elicited flight behavior; these fractions were different from fractions containing compounds that were previously identified to elicit a response in a contact bioassay.