The research at NDSU is led by Febina Mathew, NDSU Department of Plant Pathology associate professor, in collaboration with Sam Markell, NDSU Extension pathologist, professor and interim department head.
Researchers at NDSU, in collaboration with the University of Nebraska-Lincoln, have been granted $300,000 from the USDA's Agriculture and Food Research Initiative Critical Agriculture Research and Extension program. This funding aims to conduct a study on fungicide resistance in Diaporthe/Phomopsis species, which cause Phomopsis stem canker in sunflower crops.
The research initiative is recognized as the leading competitive grants program for plant health in the U.S. The CARE program, a component of AFRI, addresses six priority areas, including plant health and production, as well as plant products. The primary objective of the critical agriculture extension program is to support projects that prioritize conducting rigorous research and implementing effective Extension practices.
The research at NDSU is led by Febina Mathew, NDSU Department of Plant Pathology associate professor, in collaboration with Sam Markell, NDSU Extension pathologist, professor and interim department head.
“Phomopsis stem canker is a major disease that greatly affects sunflower yield in Minnesota, Nebraska, North Dakota and South Dakota,” says Mathew. “These states together account for more than 80% of sunflower production in the United States. In high disease pressure environments, we recommend applying a single application of Quinone outside Inhibitor fungicide during the miniature floral head growth stage of sunflower to manage this disease. Our research has demonstrated that a single fungicide application can reduce the severity of Phomopsis stem canker by up to 30% and enhance yield by 5%.”
“However, in 2022, we identified strains of Diaporthe helianthi, one of the primary fungi responsible for Phomopsis stem canker, to have complete resistance to QoI fungicides,” shares Mathew.
“Using effective fungicides is very important for managing diseases and protecting yield,” says Markell. “When the pathogens causing disease become resistant to fungicides, farmers have fewer options to protect their crops and the risk of losses increases. Our research explores an Integrated Pest Management approach of foliar fungicide application and planting Diaporthe-resistant hybrids to manage fungicide resistance and achieve higher yields.”
“We are excited to collaborate with Dr. Robert Harveson, Professor and Extension Plant Pathologist at the UNL Panhandle Research and Extension Center and the National Sunflower Association on this project,” says Mathew.
The association is a non-profit organization committed to advancing the production of sunflowers in the United States. It is directed by U.S. sunflower farmers and industry representatives.
“Sunflowers are a significant crop, used for their oil and seeds. Losses due to fungicide-resistant diseases can lead to significant economic damage for farmers and associated industries. By understanding and mitigating fungicide resistance, we can protect these economic interests,” says John Sandbakken, sunflower association executive director.
Through the proposed research, the scientists will:
• Assess the extent of QoI-resistant strains of Diaporthe species that cause Phomopsis stem canker in Minnesota, North Dakota, Nebraska and South Dakota.
• Evaluate the effectiveness of foliar fungicides that contain Succinate Dehydrogenase Inhibitor as an alternative to QoI on Diaporthe-resistant hybrids.
• Enhance the ability of farmers and agricultural professionals to manage Phomopsis stem canker by creating and providing Extension tools for their education.
As a student-focused, land-grant, research university, we serve our citizens.
