Department of Botany and Plant Pathology

David Gent Assistant Professor (Courtesy), Ph.D., 2004, Colorado State University gentd@onid.orst.edu Office/Lab: USDA/Forage Seed and Cereal Research Unit Phone: 541-738-4167

Research Area

Integrated pest management; downy and powdery mildew of hop

Description of Research

Our research centers around developing integrated management systems for hop that reduce chemical inputs for downy and powdery mildew through disease forecasting, modification of cultural practices, and host resistance.  The overall goal of our research is to develop disease management strategies that reduce production costs and improve grower profitability and sustainability.

Research Group Members

Faculty Research Assistant/Associates

Joanna Farnsworth

Graduate Students

Melanie Mitchell

Related Links

http://iapreview.ars.usda.gov/pandp/people/people.htm?personid=37109

Publications

Gent, D. H., Al-Saadi, A., Gabriel, D. W., Louws, F. J., Ishimaru, C. A., and Schwartz, H. F. 2005. Pathogenic and genetic relatedness among Xanthomonas axonopodis pv. allii and other pathovars of X. axonopodis . Phytopathol. In press

Gent, D. H., and Schwartz, H. F. 2005.  Management of Xanthomonas leaf blight of onion with a plant activator, biological control agents, and copper bactericides. Plant Dis. 89:631-639.

Gent , D. H., and Schwartz, H. F. 2005. Effect of nitrogen fertilization and seed contamination on epiphytic populations of Xanthomonas axonopodis pv. allii and development of Xanthomonas leaf blight of onion. Online. Plant Health Progress doi:10.1094/PHP-2005-0331-01-RS.

Gent , D. H., Lang, J. M., and Schwartz, H. F., 2005. Epiphytic survival of Xanthomonas axonopodis pv. allii and X . axonopodis pv. phaseoli on onion and dry bean. Plant Dis. 89: 558-564.

Gent , D. H., Lang, J. M, Bartolo, M. E., and Schwartz, H. F. 2005. Inoculum sources and survival of Xanthomonas axonopodis pv. allii in Colorado . Plant Dis. 89:507-514.

Gent , D. H., Schwartz, H. F., and Khosla, R. 2004. Distribution and incidence of Iris Yellow Spot Virus in Colorado and its relation to onion plant population and yield. Plant Disease 88:446-452..

Gent, D. H., Schwartz, H. F., Ishimaru, C. A., Louws, F. J., Cramer, R. A., and Lawrence, C. B. 2004. Polyphasic characterization of Xanthomonas strains from onion. Phytopathology 94:184-195.