Laboratory Evaluation of Virulence of Heterorhabditid Nematodes toPlodia interpunctellaHübner (Lepidoptera: Pyralidae)

Abstract

The Indianmeal moth, Plodia interpunctella (Hubner), is a cosmopolitan pest of stored products, infesting most commodities in warehouses and grain bins. We studied the susceptibility of Indianmeal moth adults and larvae to seven entomopathogenic nematode species and strains. The nematodes studied were Heterorhabditis bacteriophora Poinar (HP88, Lewiston, and Oswego strains); H. indica Poinar, Karunakar, and David (Homl strain); H. marelatus Liu and Berry (Point Reyes strain); H. megidis Poinar, Jackson, and Klein (UK211 strain); and H. zealandica Poinar (NZH3 strain). Overall, the nematodes that had the highest virulence to larvae and adults of Indianmeal moth were H. indica, H. megidis, and H. marelatus. Adult Indianmeal moths seemed to be more susceptible to the nematodes than the larvae, and egg laying was significantly reduced by at least 44% in Indianmeal moths adults that survived exposure to the nematode strains. We conclude that H. indica, H. megidis, and H. marelatus should be studied further as potential biocontrol agents of Indianmeal moth in stored grains and processed commodities.