Zanen P.O., W.J. Lewis, R.T. Carde, and B.G. Mullinix. 1989. Beneficial Arthropod Behavior Mediated By Airborne Semiochemicals: VI: Flight responses of female Microplitis croceipes (Creson), a Braconid endoparasitoid of Heliothis spp., to varying olfactory stimulus conditions created with a turbulent jet. J. Chem. Ecol. 15: 141-168.

ABSTRACT

Odor-mediated host-searching by female Microplitis croceipes, a braconid endoparasitoid of larval Heliothis species, was studied in a flight tunnel. Volatiles emmitted by third-instar H. zea feeding on cowpea seedling leaves were released and carried with the wind, resulting either in an irregulay shaped plume, or injected with high velocity, resulting in a conically shaped jet plume. Flight maneuvers of M. croceipes had a higher stereotype in jet plumes compared to irregularly shaped plumes. Variation in odor concentration in jet plumes due to intermittent feeding of the host larvae did not affect the number of flights. At the levels employed, odor concentration did not alter the rate of upwind progress in jet plumes. Because air velocity inside a jet increases in the upwind direction, M. croceipes regulates its groundspeed during its approach to the odor source.