Fusarium head blight is causing problems in irrigated wheat fields across parts of the Columbia Basin.
Field infections range from 1-2 percent up to 25 percent, said Dana Herron, a member of the Washington Grain Commission and co-owner of Tri-State Seed Co. in Connell, Wash.
“Some of those fields that were 150 bushels are only going to yield half of that,” he said.
The infection is prevalent throughout the Columbia Basin, he said.
“Without preventative measures, most people will potentially lose significant yield,” Herron said. “By the time you know you have it, it’s too late to do anything about it. The only recourse is prevention.”
Herron said he’s seeing the most damage in dark northern spring wheat planted last fall. That wheat class is currently the highest-priced on the market.
“It’s probably too late to do anything this year,” said Tim Murray, Washington State University Extension plant pathologist. “Going forward, it’s important that field consultants and farmers recognize what the problem is in the field.”
Growers can plant a resistant variety, irrigate the field before flowering and then shut water off for several weeks as the plant flowers, or spray a fungicide around flagleaf expansion and heading.
WSU spring wheat breeder Mike Pumphrey says the amount of resistance to fusarium head blight in existing germplasm is currently an unknown. He’s screening released varieties, particularly those grown in irrigated fields, with the awareness of including resistance in future varieties.
“For an irrigated grower, it’s kept me up at night for a long time,” he said. “It’s a major, primary concern.”
The disease is mainly a problem for wheat in center-pivot irrigated fields, in areas that stay wet longer. It seems to be increasing in frequency and severity, Murray said.
Spores of the fungus infect flowers of the wheat plant. Damage can range from just a few flowers to the entire head. If it infects early, it can prevent seed production. If it occurs later, the seed produced may be shriveled and unsellable.
The fungus also produces a toxin, commonly referred to as vomitoxin because infected grain fed to animals can cause vomiting.
Infected grain is likely to be cleaned out during combining and eliminated, so Murray says the primary concern is spores produced on residue from previous crops.
If a farmers plan to sell or use seed cleanings from a field that was impacted for cattle or pig food, they may want to test it for vomitoxin, he said.
An epidemic of the disease in the Midwest in the 1990s caused the malting barley industry to shift production to the West, Murray said.
Murray says fusarium head blight is becoming more prevalent because of increased corn acreage in the Columbia Basin.
The same fungi can infect corn, survive on corn residue and produce spores that can travel long distances by air.
Murray intends to include fusarium head blight in discussions with farmers during winter meetings and continue to spread the word about the disease, he said.
Herron hopes to reach out to chemical company field men about the problem.
“They don’t know how to prevent it,” he said. “As soon as they do, we’ll have a lot less of it.”