It’s bad news, but not completely unexpected.
That’s how canola industry experts are describing an Oct. 31 announcement that visible symptoms of clubroot have been detected in 35 additional fields across Saskatchewan’s northern grain-growing region this year.
The disease has now been confirmed in 37 commercial canola fields across the province’s northern grain belt over the past two years and in five of the province’s 20 crop districts.
According to some observers, its likely to show up in more areas in the future.
“We’ve known that (clubroot) has occurred in Manitoba and Alberta for a number of years now, and it was really only a matter of time until we started to see it in Saskatchewan, so that part of it wasn’t really a surprise,” said Barb Ziesman, plant disease specialist with the Saskatchewan Agriculture.
“It is a soil-borne disease so there is the potential that it is (established) in other areas of the northern growing region as well….”
Some of the latest confirmed cases were detected through Saskatchewan’s annual clubroot survey.
Other cases were reported to the ministry by growers, agronomists and rural municipalities.
Visible symptoms of the disease have been recorded in Saskat-chewan crop districts 9A, 9B, 5B, 6B and 7B.
Ziesman declined to provide specific locations of the infected fields.
Additional information will be included in the province’s clubroot distribution map, which will likely be available to growers in early 2019, she added.
At the request of growers, SaskCanola and Saskatchewan Agriculture significantly expanded the scope of the 2018 survey.
After a pair of confirmed cases in northwestern Saskatchewan in 2017, the province’s canola growers suggested that the 2018 survey be expanded.
“We heard from growers (in 2017) that they needed to get a better idea of where clubroot was in the province,” said SaskCanola research manager Errin Willenborg.
“We’re starting to see some of those results come in now.”
This year’s survey focused on high-risk production areas across Saskatchewan’s northern growing region, as well as a large production area on the eastern side of the province.
With those areas, field staff visited one canola field per township.
“For every field that we visited, we pulled up plants and looked for visible symptoms of clubroot and we also collected soil samples (that will be used) to conduct a DNA test to detect clubroot pathogens at low levels,” Ziesman said.
“We’re finished the in-field part of the survey… but we’re still waiting for the soil test results.
“Once we have all of the information from our survey, we will be developing our clubroot distribution map. That’s going to provide more clarity on the distribution of the disease across the province….”
Discussions are still taking place to determine how the information collected from soil samples should be presented, Ziesman added.
The Saskatchewan distribution map is expected to be similar to maps already produced in Alberta and Manitoba.
Soil that contains clubroot spore loads of 80,000 to 100,000 spores per gram of soil will normally produce visible symptoms in vegetative canola crops.
However, less obvious visible symptoms can be detected when loads are as low as 10,000 spores per gram.
Both Ziesman and Willenborg encouraged growers to monitor their fields for symptoms of the disease and report the findings to the ministry.
“This information is going to be really helpful as we start to develop our distribution maps and our extensions materials,” said Ziesman.
“We want to make sure that the information we share publicly is as robust and accurate as possible.”