Poster # 103

William T. Hay ¹, James A. Anderson ², David, F. Garvin ², Susan P. McCormick ¹, Mark Busman ¹, and Martha M. Vaughan ¹
1. USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Mycotoxin Prevention and Applied Microbiology Unit, 1815 N, University Street, Peoria, IL 61604, USA.
2. Department of Agronomy & Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
Corresponding Author: William Hay, william.hay@usda.gov

William Hay

Fusarium head blight (FHB) is a destructive fungal disease of wheat that causes significant economic loss due to lower yields and the contamination of grain with fungal toxins (mycotoxins), particularly deoxynivalenol (DON). FHB disease spread and mycotoxin contamination has been shown to worsen at elevated CO₂, therefore, it is important to identify climate-resilient FHB resistance. This work evaluates whether wheat with the Fhb1 quantitative trait locus (QTL), the most widely deployed FHB resistance locus in wheat breeding programs, provides reliable disease resistance at elevated CO₂. Near-isogenic wheat lines (NILs) derived from either a highly FHB susceptible or a more FHB resistant genetic background, with or without the Fhb1 QTL, were grown in growth chambers at ambient (400 ppm) and elevated (1000 ppm) CO₂ conditions. Wheat was inoculated with Fusarium graminearum and evaluated for FHB severity. At elevated CO₂, the NILs derived from more FHB-resistant wheat had increased disease spread, greater pathogen biomass and mycotoxin contamination, and lower rates of DON detoxification; this was not observed in wheat from a FHB susceptible genetic background. The Fhb1 QTL was not associated with increased disease severity in wheat grown at elevated CO₂ and provided reliable disease resistance.