Elevated CO2 Can Worsen Fusarium Head Blight Disease Severity in Wheat but the Fhb1 QTL Provides Reliable Disease Resistance

William T Hay; James A Anderson; David F Garvin; Susan P McCormick; Mark Busman; Martha M Vaughan

doi:10.3390/plants12203527

Elevated CO₂ Can Worsen Fusarium Head Blight Disease Severity in Wheat but the Fhb1 QTL Provides Reliable Disease Resistance

Plants (Basel). 2023 Oct 11;12(20):3527. doi: 10.3390/plants12203527.

Authors

William T Hay¹, James A Anderson², David F Garvin², Susan P McCormick¹, Mark Busman¹, Martha M Vaughan¹

Affiliations

¹ USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Mycotoxin Prevention and Applied Microbiology Research Unit, 1815 N, University Street, Peoria, IL 61604, USA.
² Department of Agronomy & Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA.

Abstract

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.

Keywords: Fhb1; climate resilience; elevated CO2; food safety; fusarium head blight; mycotoxins; wheat.

Grants and funding

This work was supported in part by the U.S. Department of Agriculture, Agricultural Research Service.