Fecundity and oviposition of Eucelatoria bryani, a gregarious parasitoid of Helicoverpa zea and Heliothis virescens. Entomologia Experimentalis et Applicata 75: 175–181

host-parasitoid relationship, fecundity, progeny allocation We examined longevity, fecundity, and oviposition strategies of Eucelatoria bryani Sabrosky (Diptera: Tachinidae), a gregarious endoparasitoid of Helicoverpa zea (Boddie) and Heliothis virescens (E) (Lepidoptera: Noctuidae). Longevity of adult female E. bryani was not related to body size. In contrast to longevity, larger E. bryani females had greater potential fecundity than smaller females, as determined by the number of embryonated ggs present in the common oviduct. However, female parasitoid size did not affect primary clutch size (number of eggs deposited in a host). Because mbryos in eggs located in the ovisac were larger than those located elsewhere in the common oviduct, maximum primary clutch size may be physiologically limited by the number of fully mature ggs a female has available at one time. E. bryani females adjusted primary clutch size in response to host size, for both H. zea and H. virescens. This adjustment appears to be adaptive because females did not overexploit hosts by depositing more larvae than a host could support. Adult emergence was not related to host size. Although host weight positively influenced E. bryani progeny weight, increases in progeny size with host size were counterbalanced by increases in primary clutch size with host size