USE OF A FACTITIOUS HOST AND SUPPLEMENTED ADULT DIET TO REAR AND INDUCE OOGENESIS IN CATOLACCUS-GRANDIS (HYMENOPTERA, PTEROMALIDAE)

Augmentation and release of the ectoparasitoid Catolaccus grandis (Bur ks) against the boil weevil, Anthonomus grandis grandis Boheman, has r elied on the production of boil weevils for the past 15 yr. Eliminatin g this dependence on a host that is expensive to rear could make this technology commercially viable. Seven species of insects that are more easily reared than the boil weevil were tested as factitious hosts of C. grandis. Four species were lepidopterans-Galleria mellonella (L.), Helicoverpa zea (Boddie), Heliothis virescens (F.), and Chilo plejade llus Zincken. Only H zea and H. virescens stimulated oviposition by C. grandis; nevertheless this parasitoid did not complete development in any of these lepidopterans. The other 3 species were coleopterans-Cha lcodermus aeneus Boheman, Anthanomus eugenii Cane, and Callosobruchus maculatus (F.). Females of C. grandis oviposited and parasitoids compl eted development in all coleopteran species. C. grandis females reared on C. maculatus oviposited significantly more eggs per day than those reared on A. eugenii or C. aeneus. Chemical analyses showed that the concentrations of proline, histidine, glutamine, and tyrosine in C. ma culatus and A. eugenii hemolymph most closely resembled those of A, g. grandis hemolymph. The effectiveness of the factitious hosts to stimu late oogenesis was indirectly tested by comparing oviposition rates of females exposed to the factitious hosts to those of naive females. Ev en though A. eugenii and C. maculatus stimulated oogenesis (conditioni ng) in C. grandis females after 3 d of exposure, the degree of stimula tion was significantly lower than that induced by exposure to A. g. gr andis prepupae. The results indicate that C. maculatus is a promising factitious host to rear and condition C. grandis females.