Research Program: Dr. Kluepfel’s research program explores the interaction between plants and bacteria at the interface between roots and the surrounding soil called the rhizosphere. The aim of the research is to characterize both individual bacterial species and the microbial community which occupy the rhizopshere of important fruit and nut crops such as walnut, almonds and grapes and understand how they interact and communicate with their plant hosts. Toward this end, different model plant-bacteria systems are being examined. The laboratory is examining, the behavior and pathogenecity of Agrobacterium tumefaciens, the cause of Crown Gall Disease, on walnut. In addition, a project to detect and characterize the bacterial pathogen, Brenneria rubrifaciens, that causes deep bark canker on walnut is underway. These projects are all supported by our effort to isolate and characterize all the bacterial genes whose expression is modulated by plant-root exudates during bacterial growth in the rhizosphere. This information is being used to identify individual microbial species and/or microbial communities that are beneficial to plant health and antagonistic to disease causing pathogens in the soil in an effort to develop ecologically sustainable disease control methods employing naturally occurring soil bacteria.
Biography: Dr. Daniel Kluepfel received a BA in Biology from the University of Missouri, St. Louis and then went on to receive his Ph.D. in Plant Pathology, with a minor Microbiology, from the University of Florida, Gainesville. His Ph.D. research examined the attachment of plant associated bacteria to solid surfaces. After graduation Dr. Kluepfel accepted a Fulbright Fellowship to conduct post doctoral work at the Agriculture University of the Netherlands in Wageningen. This was followed by a second post doctoral position at the Univ. of Hawaii in the Dept. of Plant Pathology where he was involved in the genetic characterization of toxin production by phytopathogenic bacteria. Dr. Kluepfel served on the faculty of the Department of Plant Pathology and Physiology at Clemson University in South Carolina from 1987-2003. In 2003 Dr. Kluepfel joined the USDA/ARS in Davis, CA.