How do endophytic turfgrasses reduce susceptibility of black cutworm and fall armyworm to entomopathogenic nematodes?
Brian A. Kunkel, Douglas R. Richmond, and Parwinder S. Grewal. The Ohio State University, Department of Entomology, 1680 Madison Ave, Wooster, OH Perennial ryegrass infected by the symbiotic fungus Neotyphodium lolii receives several competitive benefits including increased drought tolerance and decreased susceptibility to diseases and herbivory. The fungus produces a variety of alkaloids that are toxic to vertebrate and invertebrate herbivores. Two lepidopterans from the family Noctuidae, Spodoptera frugiperda and Agrotis ipsilon, are generalist herbivores that can feed on endophyte-infected perennial ryegrass and complete development. We exposed them to Steinernema carpocapsae (All), an entomopathogenic nematode that is used for biological control of these insects. In the presence of S. carpocapsae, the noctuids fed on infected grass lived significantly longer than those fed on uninfected grass. Although fall armyworm larvae fed on endophyte-infected perennial ryegrass had significan
