PATHOGENICITY OF TWO NUCLEAR POLYHEDROSIS VIRUSES IN THE BLACK CUTWORM, AGROTIS IPSILON (LEPIDOPTERA: NOCTUIDAE),

Abstract
LC50 and LT50 values for two multicapsid nuclear polyhedrosis viruses isolated from the alfalfa looper, Autographa californica (Speyer), and a mint looper, Rachiplusia ou (Guenée), were determined against black cutworm, Agrotis ipsilon (Hufnagel), neonate larvae, 1-day-old larvae reared at 15 °C before testing, and 1-day-old larvae reared at 27 °C before testing. The results showed that black cutworm larvae have low to moderate susceptibility to these viruses. As the larvae developed, their susceptibility to the viruses rapidly declined. Initial growth of larvae surviving sublethal dosages of these viruses was reduced, but pupal weights of these larvae were not significantly different from untreated controls.