Molecular Evolutionary Biology of Fusarium
Research in my laboratory focuses on several aspects of the evolutionary biology of Fusarium, a large genus of filamentous fungi that represents the single most important group of mycotoxigenic plant pathogens. Fusaria have also emerged within the past two decades as opportunistic pathogens of immuno-compromised patients. Members of this genus produce an amazing diversity of toxic secondary metabolites, such as trichothecenes (potent inhibitors of eukaryotic protein synthesis and virulence-associated factors towards sensitive plant hosts), fumonisins (suspected carcinogens) and estrogenic compounds, which pose a serious threat to human and plant health and food safety.
One of the primary goals of my research program is to develop molecular epidemiological tools for the rapid detection and identification of the most important fusarial pathogens of plants and humans. To achieve this objective, we have been using multilocus sequence typing (MLST) to identify species limits and to examine their population biology. Knowledge of species limits is essential for understanding their geographic distribution, host range and toxin potential. This information is critical in order to establish successful molecular surveillance programs for economically devastating plant diseases such as Fusarium Head Blight (FHB) of wheat and barley and Sudden Death Syndrome (SDS) of soybean. Just within the past two decades, FHB endemics in the upper Midwest of the U. S. have accounted for approximately 3 billion dollars in losses to U. S. agriculture because of low yields and price discounts due to toxin contaminated grain.
Research in my laboratory has shown that both of these diseases are caused by several genetically distinct species, some of which are non-indigenous to the United States. Our phylogenetic epidemiological studies are directed at minimizing the threat of inadvertent introductions of foreign FHB and SDS pathogens into the U. S. We are also using MLST to characterize the genetic diversity of medically important fusaria as part of multi-institution collaborative studies. Lastly, some of my research has focused on the evolution of the Mucorales and their relatives, and true morels.