Blackleg is one of the key diseases faced by Prairie canola
producers and has largely been kept in check with the use of resistant
varieties and crop rotation. However,
over the past 10-20 years there have been concerns regarding observed shifts in
blackleg pathogen virulence in response to the major gene resistance used in a
number of varieties.
Changes in virulence patterns emphasize the critical need to
stay on top of this disease; producers and crop scouts can play a critical role
by scouting fields to monitor blackleg and detect any unexpected increases in
disease levels on resistant varieties.
For blackleg a critical time for scouting is later in the season to
assess the prevalence, severity and impact of this disease issue.
When assessing blackleg incidence and severity, it is critical to correctly identify
symptoms of blackleg and differentiate these from normal or premature canola
crop ripening due to a range of abiotic and biotic factors. Recent Prairie research has shown limited
responses to in-crop fungicide when resistant varieties are grown, and
especially where this resistance is still highly effective.
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| Mid-season blackleg leaf lesion |
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| Mid-season blackleg leaf lesion |
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| Cross section of late-season blackleg stem base infection |
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| Cross section of late-season blackleg stem base infection |
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| Late-season blackleg stem base infection/canker |
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| Late-season blackleg stem base infection/canker |
Access the latest survey protocols and scouting information
for blackleg of canola at:
Blackleg survey protocols
Blackleg scouting information
Blackleg disease info card
