AN EPIZOOTIC OF NUCLEAR POLYHEDROSIS VIRUS IN ARMYWORMS (PSEUDALETIA UNIPUNCTA) IN CONNECTICUT

Northeastern Naturalist, 2004 by Magnarelli, Louis A, Andreadis, Theodore G

In addition to NPV infections, wasp parasitoids and tachinids attack P. unipuncta larvae (Britton 1938, Shcppard and Weinzierl 2002). However, we do not know if these parasitic insects play a role in disseminating NPV to uninfected caterpillars. Studies are needed to determine the origin of NPV and the primary method of virus dissemination. Overall, the impact of parasitic wasps and flies, coupled with NPV infections, contribute to the mortality of P. unipuncta caterpillar populations.

Sporadic armyworm outbreaks have immediate impact on natural and managed grass-dominated ecosystems. Extensive damage to plants can occur in less than two weeks. The root systems of grasses, however, are usually unharmed by caterpillars, and plants often recover from the damage following the sudden population collapses of armyworm populations.

ACKNOWLEDGMENTS

We thank Tia Blevins and Jason Martin for technical assistance and Michael Thomas for preparing the figures.

LITERATURE CITED

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Louis A. MAGNARELLI1,* AND THEODORE G. ANDREADIS1

1 The Connecticut Agricultural Experiment Station, 123 Huntington Street, PO Box 1 106, Now Haven, CT 06504. 'Corresponding author louis.magnarelli@po.state.ct.us.