Title: Vertically and horizontally transmitted genetic information in plant::plant and plant::microbe interactions

Jeff Bennetzen

University of Georgia, USA


Dr. Bennetzen received a Ph.D. in 1980 from the University of Washington in Seattle for investigations of gene function and evolution in brewer’s yeast. After a one-year postdoctoral fellowship and two years in the industry, he joined Purdue University as a faculty member in 1983.  In 2003, he moved to the University of Georgia as the Giles Professor.  He is an elected fellow of the US National Academy of Sciences and the American Association for the Advancement of Science. Dr. Bennetzen has published more than 200 refereed research articles.


Plants are inundated by seas of microbes in every tissue, in every environment and at every stage of development.  Some of these microbes cause disease, while a few are known to enhance plant performance by preventing disease or by improving nutrient acquisition.  Perhaps because the microbial diversity of all microbes (including beneficials) is much lower on the aerial parts of plants, diseases of these tissues are much more common than are root diseases.  Because microbes have very high population numbers and short generation times, they are expected to be the routine winners in the never-ending evolutionary arms race between virulence of pathogens and disease resistance in host plants. However, recent work has shown that plants have more sources of genetic variation than previously expected, including horizontal gene transfer and site-directed recombination. Moreover, the microbial community in any given environment is uniquely established by each unique plant genotype, providing the opportunity for plant scientists to design host genotypes that create an optimal microbial community to improve plant performance and crop yield.  This presentation will describe our experiments to map and identify the plant genes responsible for the determination of microbial composition associated with several different plant species and plant tissues.  These studies are also uncovering previously unknown beneficial microbes, and laying the groundwork for breeding crops that show excellent and durable productivity without the need for fertilizers or pesticides.