Test blackleg races in a field; make better seed decisions

September 6, 2018 – Issue 23

Got some fields with higher levels of blackleg? If average severity is moving beyond 1.5 toward 2 or more, this is a clear sign that the blackleg resistance in the variety is no longer appropriate for this particular field. The blackleg pathogen population has shifted and R-gene rotation will be required the next time canola is grown on that field – unless the plan is to take a three-year break from canola. New tests allow farmers to identify the blackleg races in their fields. With this information, farmers can choose canola varieties with resistance to those races.


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Labs can test fresh stems (taken from this year’s crop) or old stem pieces found in fields that will be seeded to canola next year.

Manitoba’s Pest Surveillance Initiative Lab.
PSI will provide a blackleg race ID test for about $200. Members of Manitoba Canola Growers, which helps fund the lab, can get one free test this year and then, like anyone else, pay $200 for extra tests if they want to check more than one field. Read more on how to take and submit samples.

Discovery Seed Labs. If stems seems to be infected, send in a 2-3” length of that infected stem. Include up to 12 stem samples. Discovery will test to confirm the presence of the blackleg pathogen, and it will test to identify the specific race. Read more.

20/20 Seed Labs. They just added a blackleg stubble test and will also provide a race ID upon request. Contact Brady at brady@2020seedlabs.ca or call 1-877-420-2099 for specific information on sampling protocols and pricing.

Read about genetic resistance and changes in pathogen populations.

Canola Watch