With wet growing conditions in many areas and high prices driving tight pulse crop rotations, the table was set for root rot to feast on pea stands in Western Canada this year.
While one of the main culprits — aphanomyces — was first confirmed in Saskatchewan in 2012 and in Alberta in 2013, testing on the pathogen has been underway for more than 20 years in southern Manitoba at Agriculture and Agri-Food Canada’s Morden Research Centre.
As AAFC pulse crop pathologist Bob Conner explains in this Pulse School episode, they’re using the aphanomyces disease nursery in Morden to identify breeding lines that carry tolerance or resistance, and to compare yields between infected and disease-free plots.
“One of the big problems for working on aphanomyces root rot is the disease is very patchy in distribution, but that doesn’t seem to be the case with the site we have,” he notes.
They’re still “a few years away,” but Conner says pea varieties that are significantly less susceptible to aphanomyces are coming, as they’ve identified several genes that provide resistance to multiple races of the disease.
“I think the prospects here are pretty good because we have access to the genetic material and the breeders are using it,” he says.
That includes breeders at the University of Saskatchewan’s Crop Development Centre, notes Conner. “That may be where we see the first varieties, coming out of there.”
Improved genetics won’t replace the need for proper crop rotation and other precautions to limit the severity of the disease, he says, but “some of these new sources of resistance — if they can be incorporated into a high-yielding pea variety — could really reduce the importance of aphanomyces root rot.”