Anniversary of scab outbreak in wheat remembered
By Carol Stender
Date Modified: 08/21/2013 7:50 AM
CROOKSTON, Minn. — It's an ominous 20th anniversary, but one that bears noting because of the persistence of farmers and plant breeders who fought scab 20 years ago.
Their determination produced funding for research that resulted in better varieties, fungicides and crop rotations to fight the disease.
It was a difficult battle.
At the beginning of the 1993 growing season, wheat and barley crops looked pretty good, said Dave Torgerson, executive director of the Minnesota Association of Wheat Growers. Many wheat producers were growing the same variety.
As they monitored their fields and prepared for harvest, they found a lot of scab.
Based on today's scales rating disease resistance and standability traits, with 1 being the best and 9 the worst, those varieties would probably rate an 8 for scab, said Minnesota wheat breeder Jim Anderson.
The problem was so bad that some companies weren't buying small grain because of fears of vomitoxin, he said. Instead of harvesting it, some farmers chose to burn it.
Scab had been reported in small grains in the 1800s and had become an epidemic throughout the 1900s, said Anderson.
"That was one of the reasons why wheat production moved north," he said.
Wheat wasn't being grown in southern and southwestern Minnesota because corn wasn't a good rotation partner, he said.
Farmers two decades ago thought scab would go away after one year, said Torgerson.
Anderson was in his second year of small grain research at North Dakota State University when the disease hit.
"The wheat breeder and other researchers said they knew this could happen, but they thought this was a 100-year event, like a 100-year flood," he said. "Then in 1994, the disease came back again, not quite as severe, but it got people's attention."
Wet weather coupled with reduced tillage and planting wheat following wheat added to disease problems, he said.
Minnesota farmers weren't the only ones with scab issues, Torgerson said. Michigan also was having problems. Growers from the two states, along with plant breeders and small grain researchers, worked together to get a funding initiative through Congress.
Minnesota funded the research to the tune of $1.6 million over two years, Torgerson said.
"MAWG was instrumental in getting both state and federal funds to research the disease," Anderson said. "If we didn't have that support, we wouldn't have the research and development that we have now."
Researchers used Chinese wheat germplasm that exhibited scab resistant traits to develop new varieties.
While varietal selection plays a part in fighting disease, Anderson stresses that tillage, use of fungicides and crop rotation are also important.
The scab outbreak and movement of hardier corn and soybean varieties to northern Minnesota resulted in a drop of wheat acres. Minnesota had 2.7 million acres in 1992 and 1993, Anderson said. Now, wheat is grown on 1.4 million to 1.6 million wheat acres.