Barley is a significant Canadian crop that provided approximately $2.3 billion in revenue to producers, maltsters and exporters in 2019. To build on Canada’s position as a supplier of premium quality barley and malt requires developing barley varieties with improved resistance to Fusarium head blight (FHB), or more specifically, resistance to deoxynivalenol (DON) accumulation. The economic impact of FHB across the Canadian cereal industry has been estimated to be somewhere between $50-300 million annually. The purpose of this project was to support activities that would assist in the breeding of barley varieties with improved resistance to DON accumulation, including: 1) evaluation of CDC breeding lines for low DON accumulation, 2) development of tools and methods to conduct DON screening at the CDC, 3) improvement of predictive NIR calibrations of barley grain DON content for use as a screening tool in breeding programs and, 4) evaluation of a genetic population for the purpose of identifying QTL linked to low DON accumulation that could be used as a screening tool in breeding programs.

Approximately 2,250 breeding lines were evaluated for DON content each year with 9-26% of the feed/forage lines and 13-41% of the malting lines showing DON accumulation below that of the low DON check line CDC Mindon. A total of 39 breeding lines that were evaluated under this project were advanced to the western Canadian cooperative registration tests with 80% of them receiving an FHB rating that met or exceeded the intermediate resistance rating required for registration. A total of 5,415 breeding lines were evaluated for DON content at the CDC using the Gallery analyzer and Diagnostix EZ-Tox™ DON kit. DON values obtained from the CDC showed a correlation of r=0.93 to those obtained from a commercial lab. A correlation of 0.57 was observed between the CDC NIR prediction for DON and DON values obtained from the Gallery analyzer using 1,042 lines. A 169-member genetic mapping population was genotyped and evaluated for DON, FHB score, heading date and height. Seven genomic regions were identified as influencing DON content and importantly none of these regions were associated with heading date or height.

A number of significant accomplishments were made through this project including, 1) two lines evaluated under this project, CDC Valdres (HB17340) hulless food barley and CDC Renegade (FB209) forage barley, were registered for commercial production, with one feed barley (TR19175) likely to be registered in 2021, 2) the CDC is now able to evaluate all its breeding lines for DON and make selection decisions based on this information prior spring seeding. This represents a significant achievement in our ability to breed for improved DON tolerance, 3) the NIR prediction for DON content was improved during this project (r=0.57) when compared to the previous 5-year project (r=0.38) and, 4) the seven genomic regions associated with DON content each show a low effect on DON, but collectively they will have value when incorporated as fixed variables into genomic selection models that can be used by breeders to select barley lines with low DON content.