St. Paul, Minn. (May 1, 1999)— Six successive years of disease have taken their toll on many small grain farmers in the Red River Valley of North Dakota, Minnesota, and Manitoba. This extended episode is bringing ruin to many farmers in the region. Additional outbreaks in the midwestern and eastern United States, as well as central and eastern Canada, are leaving thousands of farmers searching for solutions. The culprit responsible for the vast devastation is Fusarium head blight, more commonly known as scab. This all consuming fungal disease shrivels the kernels of small grains such as wheat, rye and barley, significantly reducing yields.
"Moisture, at the time of flowering, is the main stimulus necessary for scab," says Robert W. Stack, plant pathologist at North Dakota State University and a member of The American Phytopathological Society. "If a wet environment exists for an extended period, even with low levels of the fungus in the field or temperatures that aren’t usually favorable to disease development, severe scab disease can result."
During the first part of this century, scab was considered a major threat to wheat and barley and recently it has resurfaced worldwide increasing in intensity. A succession of "wet cycle" years beginning in 1993 are linked to the current scab epidemic. According to the United States Department of Agriculture (USDA), "From 1991 to 1997, American farmers lost 470 million bushels of wheat, worth $2.6 billion, because of the scab epidemic." These substantial losses recently provoked a national response resulting in the development of the "US Wheat and Barley Scab Initiative," a consortium of scientists and agribusiness leaders working together to solve the scab epidemic.
Researchers are on the threshold of major breakthroughs using new methods and technologies to solve this disease problem," says Stack. "Breeding for disease resistance is underway worldwide and soon new cultivars with increased resistance to scab and developed by conventional breeding methods will be available."
For more information on scab, visit the APS feature story with photographs and links to additional sites at www.apsnet.org/publications/apsnetfeatures/Pages/HeadBlight.aspx. The American Phytopathological Society (APS) is a professional scientific organization dedicated to the study and control of plant disease with 5,000 members worldwide.
