D3105: (1st Place) Use of native entomopathogenic fungi for microbial control of insect pests of turfgrass

Entomopathogenic fungi may provide an environmentally safe and effective alternative to chemical insecticides for pest management. Only two species of these pathogens have been commercialized in the United States for turfgrass production, Beauveria bassiana GHA (e.g., Botanigard) and Metarhizium brunneum F52 (e.g., Met52). As adaptation to local environments could improve the efficacy of biological control organisms, thirty-seven novel strains of entomopathogenic fungi were isolated from soils of several horticultural sites in Oklahoma in 2014. After screening strains in lab bioassays, four M. robertsii strains and one M. lepidiotae strain were selected and evaluated against turf-defoliating black cutworm (Agrotis ipsilon) larvae using lab bioassays and field trials. Preliminary research on black cutworm contributed to the selection of the five Metarhizium strains for this study, which were compared with commercially available M. brunneum strain F52. In the current study, the efficacy of these six Metarhizium strains were evaluated against larvae of the turfgrass pests, fall armyworm (Spodoptera frugiperda) and Japanese beetle (Popillia japonica), in lab bioassays and field trials. Additionally, the potential of each fungal strain to colonize the roots of bermudagrass and bentgrass were assessed. Results of all experiments will be presented and discussed, emphasizing the potential for these endemic strains of entomopathogenic fungi for biological control of key insect pests of turfgrass.