Professor and Chair
- November 2005 – present: Chair, Department of Plant Pathology and Microbiology.
- July 2006 – present: Professor, Department of Plant Pathology and Microbiology, Iowa State University.
- March 2004 – September 2006: Interim Director, Center for Plant Responses to Environmental Stresses (CPRES)
- August 2002 – July 2004: Chair of the Interdepartmental Graduate Major at Iowa State University.
- July 2000 – June 2006: Associate Professor, Department of Plant Pathology, Iowa State University; research focused on the compatible interaction of cyst nematodes with their hosts with the long-range goal of engineering novel plant resistances.
- September 1995 - June 2000: Assistant Professor, Department of Plant Pathology, Iowa State University; research focused on the compatible interaction of cyst nematodes with their hosts with the long-range goal of engineering novel plant resistances.
- October 1993 - August 1995: Postdoctoral Researcher, Department of Plant Pathology, University of Georgia; worked in the laboratory of Dr. R. S. Hussey on identification of root-knot nematode secretion genes and on ‘plantibodies’.
- August 1989 - September 1993: Graduate Research Assistant, Department of Plant Pathology and Physiology, Clemson University; worked on root-knot nematode species interactions, molecular identification, and phylogeny, with Drs. S. A. Lewis, B. A Fortnum, and R. A. Dean as co-advisors. Thesis title: Population Dynamics and Species Identification of Root-Knot Nematodes in Tobacco.
- May 1987 - May 1989: Graduate Research Assistant, Department of Plant Pathology, Technical University of Munich; worked on fungal diseases of wheat in field and laboratory experiments, with Prof. Dr. G. M. Hoffmann and Prof. Dr. J. A. Verreet as advisors. Thesis title (translated): Epidemiology and Control of the Eyespot Disease (Pseudocercosporella herpotrichoides [Fron] Deighton) in a Wheat Monoculture.
- February - March 1987: Student Intern at the BASF Experiment Station, Limburgerhof; was involved in establishing, maintaining, and evaluating field experiments for chemical screenings.
- September 1985 - August 1986: Student Intern at two farms in Germany; was involved in the production of a wide variety of field crops (small grains, canola, beets, beans, etc.) and keeping of livestock (dairy cows, hogs, chickens, etc.).
Area of Expertise:
Ph.D. (Plant Pathology): Clemson University, 1993
M.S.-equivalent (Agricultural Sciences): Technical University of Munich, Germany 1989
B.S.-equivalent (Agricultural Sciences): University of Bonn, Germany 1985