Drew Olson (he/him/his)
Department of Plant Pathology, University of Georgia
Athens, Georgia, United States
Justin Vaughn
Genomics and Bioinformatics Research, USDA-ARS
Athens, Georgia, United States
Paul Severns, PhD
Assistant Professor of Plant Disease Epidemiology
Department of Plant Pathology, University of Georgia
Athens, Georgia, United States
Marin Brewer
Professor of Mycology and William Terrell Distinguished Professor
Department of Plant Pathology, University of Georgia, Athens
Athens, Georgia, United States
Robert C. Kemerait, Jr., PhD
Professor
UGA Dept of Plant Pathology
Tifton, GA, USA
Anthony E. Glenn
Supervisory Plant Pathologist (Research Leader)
Toxicology and Mycotoxin Research Unit, USNPRC, USDA-ARS
Athens, Georgia, United States
Fusarium fujikuroi (Ff) is a well-known plant pathogen that causes bakanae disease in rice, which can lead to economically significant levels of lodging through overproduction of gibberellic acid. Ff can also produce fumonisin mycotoxins, contaminating food and feed supplies. Recently, isolates of concerningly high-fumonisin producing Ff were found in Alabama, Georgia, and North Carolina vineyards co-occurring with isolates of a closely related, high-fumonisin producing species, F. proliferatum (Fp). Although Ff and Fp have not been shown to hybridize in nature, preliminary phylogenetic data based on intergenic spacer sequences suggested two closely related but distinct groups comprised of Ff and Fp with some isolates displaying phylogenetic incongruence, suggesting potential hybridization. Nonetheless, introgression and population genomic data from whole genome sequences and single copy ortholog phylogenies suggest that introgression may not play a major role, and earlier phylogenetic discordance may be due to high divergence within and between both species. These analyses suggest that there are at least two major clades of Ff and that Fp exhibits relatively high diversity. Moreover, some Fp genomes had apparent rearrangements that could not be explained by the Ff isolates in our study. We are presently investigating the roles of these two fumonisin producing fungi and attempting to understand whether the apparent functional genomic differences within and between the Ff and Fp groups can generate important insights for disease management and food safety.