SUSCEPTIBILITY OF PUPA OF CABBAGE LOOPER, TRICHOPLUSIA NI, TO NUCLEOPOLYHEDROSIS VIRUS .I. GENERAL RESPONES

When the response of pupae and the resultant adults of the cabbage looper, Trichoplusia ni, to a nucleopolyhedrosis virus was studied, the pupae and moths emerging from healthy larvae or the few surviving larvae fed polyhedra or injected with virus, did not differ significantly in percentage pupal mortality, percentage emergence, percentage deformed moths, mean longevity, mean matings/female, mean eggs laid, and percentage fertility. The data also indicate that diseased larvae seldom pupate or give rise to moths. Cabbage-looper pupae were susceptible to nucleopolyhedrosis virus administered via injection, but emergence of moths was not prevented unless high titers were injected. This response also depends upon pupal age, but sex was not a significant factor. However, moths emerging from pupae injected with virus were frequently deformed, and many lacked the dark pigmentation of normal adults. No vertical transmission was observed in the limited number of moths emerging from larvae inoculated with polyhedra or virus or from pupae injected with polyhedra. © 1969.