The role of plant-associated microbes in regulating plant-herbivore interactions is an emerging research focus in plant science and community ecology. However, research in this area focused primarily on a few groups of plant-associated microbes such as mycorrhizae, plant-growth-promoting bacteria, and aerial obligate symbionts in grasses. The diverse endophytic fungi in roots receive far less attention and their importance in mediating plant defense, especially against root feeding insects, remains unclear. Our lab is investigating whether horizontally-transferred fungal endophytes can regulate plant defense against belowground herbivores. We are examining the effects of endophyte colonization on plant tissue chemistry as well as their influence on the production of volatile organic compounds in soils for plant indirect defense.
Biological control is a promising tool for managing pests while preserving the environment and keeping workers and turfgrass users safe. However, many unknowns remain about biological control in soil, limiting our ability to effectively manage belowground pests. We evaluate the efficacy of insect pathogenic nematodes and fungi against soil pests such as white grubs in athletic fields and annual bluegrass weevil in golf course turf. We also conduct basic research into how biological control organisms fit into the broader soil environment, and how soil management practices and interactions with the soil community affect their performance.