Dr. Klosterman is a research molecular biologist with USDA-ARS in Salinas, California. His research has focused on the pathogenic fungus Verticillium dahliae, the cause of Verticillium wilt disease of over 200 plant species. He guided the research on the first genome publication on V. dahliae, research that laid the foundation for subsequent studies worldwide investigating the molecular genetics of this pathogen. His research has also focused on the epidemiology and molecular diagnostics of airborne pathogens affecting spinach and lettuce: Peronospora effusa, the cause of spinach downy mildew, and Bremia lactucae, the cause of lettuce downy mildew. He has led studies investigating viability and the transmission of seedborne P. effusa and seedborne V. dahliae. Since 2020, he has served as Editor-In-Chief or Associate Editor-In-Chief for the American Phytopathological Society (APS) journal PhytoFrontiers. He received the APS Fellow Award in 2025.
Dr. Klosterman received his B.S. from Wright State University in Dayton, Ohio, and his M.S. and Ph.D. in Plant Pathology from Washington State University. He conducted nearly four years of postdoctoral research at the University of Georgia prior to joining ARS in 2006.