Features Plant Breeding
Improved winter wheat cultivars for Western Canada

Breeding programs in Western Canada have a long history of developing superior winter wheat cultivars that enhance competitiveness and reduce business risk for growers and end-users across the value chain. Winter wheat breeder Rob Graf, Agriculture and Agri-Food Canada (AAFC) Lethbridge Research and Development Centre, and collaborators delivered a successful five-year cluster project that evaluated a large pipeline of germplasm between 2018 and 2023. The project resulted in the release of multiple varieties, including AAC Overdrive, AAC Coldfront, AAC Vortex and AAC Network.

Over the past 10 to 15 years, several varieties have been released out of the AAFC winter wheat breeding program, addressing key challenges, including disease resistance, improved end-use quality and higher yields. Graf retired in 2022, and his successor, Harwinder Sidhu, is now leading the AAFC breeding program at Lethbridge to continue to develop superior winter wheat cultivars for Western Canada. 

“This past project provided a good guideline and framework for moving forward with the next research cluster proposal and to where the winter wheat breeding program should advance,” says Harwinder Sidhu, research scientist. “When I came into the position, I was fortunate to overlap with Dr. Graf for a year before he retired. He showed me the diversity of the winter wheat germplasm pipeline available in the program and what we can do with it in the future, while keeping focused on the key priorities including higher yielding varieties.” 

Going forward, the goals of the next five-year cluster project proposal is to stay the course of improving disease resistance and continuously improving quality, but also adding in a focus on improving heat and drought tolerance to ultimately improve yield. The severe drought in 2021 in Western Canada impacted yields and productivity of many crops including winter wheat.

“With climate change foreshadowing these events that are expected to happen more frequently, it is important to focus on improving heat and drought tolerance in winter wheat production,” adds Sidhu. “The first objective of the cluster project proposal is to improve winter wheat productivity and abiotic stress tolerance for Western Canada. This advances the ongoing priority of improving winter wheat survival over winter, but also addresses challenges due to heat and drought in the spring. The second objective is to develop winter wheat germplasm with robust disease and pest resistance, improving genetics to bolster resistance. This objective continues the long standing priority of improved and more durable resistance to diseases, particularly stem rust, leaf rust, stripe rust, Fusarium head blight and common bunt, and insects such as wheat curl mite and wheat stem sawfly.” 

The third objective brings in a new focus and strategy for improving winter wheat quality traits. Sidhu notes that selecting quality traits can be challenging with the short time period between seed harvest and fall seeding that doesn’t allow enough time to review quality data of the advanced lines. Therefore, the objective is to utilize genomic prediction and modelling techniques that will assist breeders in selecting lines that have better quality than others. The models will help with the selection process, allowing breeders to then test and review the quality data to determine if the prediction models are helpful and selected lines meet the quality criteria. This is a long-term endeavour to collect genomic quality data and improve the prediction capabilities for trait selection. 

“Our primary focus in winter wheat breeding continues to provide the best options to growers so they can get excited about growing winter wheat,” says Sidhu. “Our breeding program has definitely improved yield and profits for growers, along with lowering input costs through improved disease resistance. Newer varieties also provide enhanced nutrient and water use efficiency and end-use quality characteristics that reflect customer demand. We continue to promote the improved varieties released in the last 10 years, such as AAC Coldfront, AAC Wildfire and AAC Gateway that all offer excellent disease resistance, and maintain an excitement of what is coming in the future. We want growers to look at winter wheat as a really good rotation option that provides good ground cover over winter and a 10 to 15 per cent yield advantage over spring wheat.” 

Sidhu encourages growers to reach out to him and his team for recommendations on varieties and tips on how to include winter wheat in rotations.

“ACC Network is the most recent release that offers excellent winter survival, good quality, a good disease resistance package and, compared to AAC Wildfire, is shorter in height with comparable yields. The new varieties are really promising and address a lot of challenges that were there in the last 10 to 15 years, and I think growers will be happy if they pick one of these new options. Winter wheat may become even more interesting to growers as a way to address sustainability and manage risks of changing climate and growing conditions, such as drier summers and drought conditions. Through our breeding program, we can provide growers with options that are high yielding, profitable and improved end-use quality.”