Fusarium head blight has cost Canada’s grain trade well over $1 billion since it first appeared in a big way in Ontario in the mid-1980s and spread across the West, says Randy Clear of the Canadian Grain Commission.
Speaking to a recent conference, he said researchers looking for a way to combat the disease, which can be fatal to humans if passed on through bread and bakery products, have made slow but promising advances including the development of a wheat variety that appears to offer high resistance to fusarium. They are also looking at its impact on barley, oats and corn.
“While the grain industry has developed ways of handling infected grain, producers have had less success reducing disease levels,” he said. “Development of improved varieties has been slow, and better management practices have limited effect. In the worst affected areas, entire classes of grain have essentially been lost to producers.”
Facing ever-increasing safety demands and regulations, “the urgency for improved varieties is stronger than ever,” he added. “In Manitoba, the number of varieties rated as poor to very poor for fusarium resistance is actually increasing and they presently account for a sizable percentage of the planted acreage. In 2008, 53 per cent of the CWRS acreage in Manitoba was planted to varieties rated as poor and very poor for fusarium. This no doubt contributed to over 50 per cent of the Manitoba CWRS crop being downgraded due to fusarium in 2008.”
Manitoba durum production has dropped sharply because of fusarium, he explained. “In 2008, only 0.3 per cent of Manitoba acres were planted to durum. Acreage planted to malting barley varieties, especially six-row varieties, has also declined in Manitoba in the last decade and little of it is now accepted for malting.”
Agriculture Canada scientist Ron DePauw said staff at the Swift Current agriculture research centre have developed a Carberry wheat variety that “sets a new standard for resistance to fusarium head blight coupled with high grain yield, high protein concentration, semi-dwarf stature with strong straw, and resistance to leaf rust, stem rust and common bunt.” The wheat is based on moving gene traits among varieties to achieve its hardiness and productive qualities.
Gordon Harrison, head of the Canadian Millers Association, said the conference showed that gaining ground in the battle against fusarium takes time and a lot of research. But the development of Carberry wheat may finally give farmers and the food industry something to cheer about.
In the 1990s, Health Canada established safety limits on fusarium-infected wheat, generally one part per million, which the Prairie industry can cope with better because of its ability to blend grain. Eastern Canada has a much smaller crop and less blending opportunities, he noted. While grain can be tested for the presence of fusarium, the system is neither rapid nor economical forcing the grain-handling system “to rely primarily on the grading system to manage the safety and quality of the grain.”
The spread of fusarium has had profound effects on the variety and classes of grain grown in both Eastern and Western Canada, he added. “In the early 1990s, growers in Ontario began to switch to Soft Red Winter wheat from traditional winter wheat, initially in a desire to try a bread-making wheat. The better sprout resistance and FHB tolerance of the red wheat has resulted in a steady decline in the acreage of CEWW to where little CEWW is now grown. Even now, eight of 10 CEWW but only seven of 15 CESRW varieties are listed as susceptible or highly susceptible.
“The burden of lower grades and reduced crop selection falls hardest on the producers,” he added. “Although the handling system has demonstrated an ability to protect our wheat exports, further expansion of the affected area and changes to the pathogen population will reduce its effectiveness.” Combined with ever-increasing demands and regulations in the marketplace, the urgency for improved varieties is stronger than ever.