Solving a billion-dollar problem: Identifying disease-resistant wheat genes
Every year, farmers across the country lose an average of 20% of their crops to disease and pests. According to the American Phytopathological Society, a group dedicated to the study of plant diseases, this adds up to $700 million in lost income annually for U.S. wheat farmers. Add to that the cost of trying to counteract these diseases with fungicides, and this is more than a billion-dollar issue for the wheat industry.
“It’s a constant struggle to stay ahead of wheat diseases — this is the main reason that the South Dakota Wheat Commission has chosen to fund Dr. Gazala Ameen’s work,” said Jon Kleinjan, South Dakota Wheat Commission executive director. “She has done an excellent job monitoring disease pressure in South Dakota and screening breeding lines and varieties for disease resistance. We are excited to see if Dr. Ameen can identify innovative ways to help fight diseases that are impacting South Dakota wheat growers.”
As Kleinjan alluded to, combatting wheat disease pressure doesn’t have a one-size-fits-all or set-it-and-forget-it solution. Which diseases are common and their severity change depending on where the wheat is grown. The pathogens that cause these diseases are continuously evolving, adapting to chemical and genetic strategies that farmers and scientists have worked together to develop. The problem requires ongoing efforts to try and stay a step ahead with disease management strategies, including identifying genetics that show resistance and combining them with high-yielding wheat varieties.
Ameen, assistant professor in the Department of Agronomy, Horticulture and Plant Science at ĢƵ, is focused on the latter. She is a plant pathologist with molecular biology training, giving her a strong understanding of both the evolving pathogens that cause disease and the plant’s ability to defend against them
“My master’s work was applied plant pathology, and my Ph.D. was focused on understanding plant resistance and its interaction with pathogens,” said Ameen, who received both degrees from North Dakota State University. “I really wanted to address immediate growers’ needs by integrating modern scientific tools and also discoveries that advance understanding of plant immunity mechanisms, which is what I can do at SDSU.”
Ameen’s work focuses on immunity receptors, proteins in plant cells that interact with pathogens and are responsible for defending the plant. Shortly after joining SDSU in 2021, Ameen worked with growers on a disease survey of pathogens affecting wheat in South Dakota. This led to realizing a gap in the research that fit her skillset.
Despite their prevalence in the state, there was a gap in looking for solutions for bacterial leaf streak, also known as scab. Ameen began analyzing the genetics of wheat varieties from around the world, looking for novel regions in the genome that could potentially offer resistance.
In the last five years, in collaboration with partners from around the world, Ameen and her team have evaluated more than 2,000 wheat lines. The group has discovered disease resistance in winter, spring and durum varieties and has identified genetic resistance against some of the most common disease threats to South Dakota wheat, including spot blotch and Ameen’s specialty, bacterial leaf streak. Additional analysis is being done to pinpoint the specific genes within the wheat that are providing protection, also known as immunity receptors.
“We identified regions that are providing resistance. However, those regions are still large, so we do not know exactly which gene is providing the resistance,” Ameen said. “We are currently using validation tools to prove the functional role of the identified genes. Ultimately, we are hoping that these discoveries allow us to fine-tune disease-resistant genes for durability and broad-spectrum resistance.”
The genes Ameen identifies as immunity receptors are shared globally with wheat breeders and scientists, with the goal of helping them develop wheat varieties that provide the most protection against the diseases causing issues locally and to give farmers around the world a fighting chance against this costly problem.
Ameen’s research contributions are being recognized. Her national and international collaboration led to her organizing the fifth annual International Bacterial Leaf Streak ĢƵ Conference, hosted at SDSU earlier this year. She has also been awarded a highly competitive U.S. Department of Agriculture-National Institute of Food and Agriculture grant to support future bacterial leaf streak research.
The foundational research being done at SDSU not only supports farmers around the state but also advances the scientific community’s understanding of plant immunity and contributes to long-term strategies for sustainable and resilient plant disease management. By improving the process, the work can lead to a high-quality product for consumers who depend on wheat for their daily nutrition.
“The best part of my research is that I am able to contribute to the global food security mission, and I can have a broader impact,” Ameen said.
