|Hojilla-Evangelista, Milagros - Mila|
|Dunn, Robert - Bob|
Submitted to: Global Change Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/14/2020
Publication Date: 5/15/2020
Citation: Hay, W.T., McCormick, S.P., Hojilla-Evangelista, M.P., Bowman, M.J., Dunn, R.O., Teresi, J.M., Berhow, M.A., Vaughan, M.M. 2020. Changes in wheat nutritional content at elevated [CO2] alter Fusarium graminearum growth and mycotoxin production on grain. Global Change Biology. 68(23):6297-6307. https://doi.org/10.1021/acs.jafc.0c01308.
Interpretive Summary: Rising carbon dioxide in the atmosphere can change wheat nutritional content and increase the severity of head blight, a devastating fungal disease of wheat that reduces yield and contaminates grain with harmful toxins. USDA scientists at the National Center for Agricultural Utilization Research discovered that some wheat cultivars will suffer greater nutrient composition losses than others at elevated [CO2]. This will likely affect cultivar planting choices because of the potential for reduced grain end use quality and increased susceptibility to mycotoxingenic fungal pathogens, or reduced efficacy of resistance traits. Therefore, head blight control strategies should include efforts to maintain wheat nutritional content.
Technical Abstract: Rising atmospheric [CO2] has been shown to impact plant primary metabolism and the severity of Fusarium head blight (FHB) in wheat. In this study, we evaluated how changes in grain nutritional content due to growth at elevated [CO2] affected Fusarium graminearum growth and mycotoxin production. Susceptible (Norm) and moderately resistant (Alsen) hard spring wheat grains that had been grown at ambient (400 ppm) or elevated [CO2] (800 ppm) were independently inoculated with two F. graminearum fungal strains, which produce the trichothecene mycotoxin, deoxynivalenol. Under higher [CO2], FHB-susceptible and moderately resistant wheat had disproportionate losses in protein and mineral contents, with Alsen being more severely impacted. Furthermore, the F. graminearum strain 9F1 had increased mycotoxin biosynthesis in response to the loss of wheat nutritional content in Alsen. Our results demonstrate that future [CO2] conditions may provide a strain-specific pathogenic advantage on hosts, with greater losses in nutritional content.