KAIROMONES AND THEIR USE FOR MANAGEMENT OF ENTOMOPHAGOUS INSECTS .9. INVESTIGATIONS OF VARIOUS KAIROMONE-TREATMENT PATTERNS FOR TRICHOGRAMMA-SPP (HYMENOPTERA, TRICHOGRAMMATIDAE)

A kairomone from adult Heliothis zea (Boddie) scales is an important factor in the host selection process of Trichogrammapretiosum Riley. If the host density is sufficiently high (i.e., 1 egg/500 cm2) and higher), a complete coverage or solid treatment of kairomone spray may be the optimum for increasing parasitization rates, but this is not the case at lower host densities (e.g., 1 egg/2000 cm2). At the lower densities, the kairomone must be distributed in such a way as to retain the parasitoids in the target area without inhibiting their movement from one ovi-position site to the next. Simulated moth scale particles appear to fill this need since their density can be regulated to provide the optimum frequency of parasitoid stimulation and thus maximum rates of parasitization at prevailing host densities. © 1979 Plenum Publishing Corporation.