|CUPERLOVIC-CULF, MIROSLAV - National Research Council - Canada|
|BAKKER, MATTHEW - Former ARS Employee|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/23/2020
Publication Date: 3/26/2020
Citation: Ward, T.J., Vaughan, M.M., Cuperlovic-Culf, M., McCormick, S.P., Bakker, M. 2020. Fusarium pathogenomics and population-specific differences during wheat infection. Meeting Abstract. [abstract].
Technical Abstract: Fusarium graminearum (Fg) is the primary fungal pathogen responsible for Fusarium head blight (FHB), a devastating disease of wheat and barley worldwide. FHB reduces crop yield and contaminates grain with trichothecene mycotoxins that are harmful to plant, human and animal health. To elucidate population structure and identify genomic targets of selection within major FHB pathogen populations in North America we sequenced the genomes of 60 diverse Fg isolates. We also assembled the first pan-genome for Fg to clarify population-level differences in gene content potentially contributing to pathogen diversity. As a result, we identified three genetically distinct populations of Fg, each associated with a different trichothecene chemotype, in North America (NA1, NA2, and NA3). Our results indicated that Fg populations are distinguished by dozens of genes with signatures of selection and an array of dispensable accessory genes, suggesting that FHB pathogen populations may be equipped with different traits to exploit the agroecosystem. To determine how this population-level diversity influences pathogenesis and mycotoxin contamination, we inoculated moderately resistant hard red spring wheat variety Alsen with 15 representative strains from each NA population and evaluated disease progression, mycotoxin accumulation, and fungal biomass. Additionally, we documented that antagonistic intrapopulation interactions can influence FHB, and that antagonism was more pronounced for NA1 than NA2 isolates.