Oviposition day effect on incidence of agonadal progeny of Helicoverpa zea (Lepidoptera: Noctuidae) infected with a virus

An agonadal condition of moths in a laboratory colony of com earworm, Helicoverpa tea (Boddie), was studied. This condition was associated with nonoccluded baculovirus like particles which replicated in parts of the abnormal reproductive tracts of agonadal moths and some apparently normal, i.e., fertile, moths. Agonadal female moths exhibited a waxy plug protruding from the vulva. This plug consisted of almost pure virus like particles within vesicles. The incidence of agonadal progeny in a colony increases with oviposition day from 5.4% for day 1 and 17% for day 2 to 62.8% for day 3. Using an aqueous suspension of material from the waxy plug as inoculum to inject 3- and 4-d-old larvae and to surface-treat eggs, the agonadal condition was produced in moths from a colony of H. tea that had never exhibited the condition. The agonadal condition was produced in progeny of moths that fed on a suspension of virus like particles, and there was an increase in the incidence of agonadal progeny with progressive oviposition day of infected female parents. An increase in the incidence of agonadal progeny with progressive oviposition day also occurred in progeny of female moths from a noninfected colony mated to males From the infected colony.