Is blackleg resistance breaking down in current canola varieties? The only way to really know is to first scout (swath-timing, harvest and post-harvest are all great times to scout) for the disease and confirm infection. Resistant varieties may still become infected, so seeing infected plants in your crop isn’t necessarily cause for alarm, but if more than 50% of plants of a resistant variety show signs of infection, the blackleg pathogen may be evolving to overcome the resistance. (Editor’s note: If you’ve found severe blackleg infection in fields seeded to a Resistant-rated variety, contact your Canola Council of Canada rep).
In this episode of the Canola School, Dr. Ralph Lange, of Alberta Innovates Technologies Futures, expands on his earlier discussion of scouting for blackleg, and discusses not only how confirmation of the disease may impact crop rotations, but also how variety selection may have to evolve in the face of resistance breakdown. Watch this episode to learn why fungicides aren’t as strong a management tool for this disease, how the blackleg pathogen is changing and what the ideal canola rotation timing is.
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