VIRULENCE OF ENTOMOPATHOGENIC NEMATODE–BACTERIA COMPLEXES FOR LARVAE OF NOCTUIDS, A GEOMETRID, AND A PYRALID

Abstract

AbstractNine entomopathogenic nematode–bacteria complexes were screened for their virulence against larvae of six noctuids, a geometrid, and a pyralid. Ninety-six-hour LD50’s of steinernematids (and heterorhabditids) ranged from 1 to 3 (1–8) infective juveniles in Galleria mellonella (L.), 1–71 (2) in Peridroma soucia (Hbn.), 1–10 (1–3) in Mamestra configurata (Wlk.), 1–28 (3–7) in Euxoa ochrogaster (Gn.), 19 in Lacanobia radix (Wlk.), 22–60 (4) in Pseudaletia unipuncta (Haw.), 2–95 (111) in Agrotis ipsilon (Hufn.), and 3–28 in Paleacrita vernata (Peck). The nematode, Steinernema feltiae LIC, a cold-hardy strain isolated in Newfoundland, was highly virulent for G. mellonella and M. configurata, but not for P. soucia and E. ochrogaster. The number of nematodes invading larvae and the number produced were greater in G. mellonella than in other insects tested. Nematode–bacteria complexes that showed potential for controlling cutworms included S. feltiae, S. glaseri, S. bibionis, Heterorhabditis bacteriophora, and H. heliothidis.