Agriculture

Surveillance of Canola Diseases in Manitoba

Canola is an economically important crop produced in Manitoba, but continued profitability relies on management of pest, such as diseases. Annual disease surveys of canola crops give valuable information on distribution in the province and impact of farming practices on incidence and severity.

Results from disease surveys help farmers, agronomists and researchers prioritize where future research is needed and provides early warning about new diseases or varietal resistance/pesticide failure.

Annual canola disease surveys have been occurring in Manitoba since 1971 with collaboration from Agriculture and Agri-Food Canada (AAFC), Manitoba Agriculture and Resource Development (MB ARD). 

In more recent surveys (2009 to present), AAFC Brandon and MB ARD have targeted 150-200 fields annually across the canola growing regions of Manitoba.  Surveys occur as canola is ripening (30-40% seed colour change) to assess for the prevalence (% crop infested) and incidence (%plant infected) of Sclerotinia, Blackleg, Aster Yellows, Alternaria, Foot Rot, Fusarium Wilt, Verticillium Stripe (or Wilt) and Clubroot.

In each field, 100 plants are selected from a “W” pattern, where the five points of the “W” are at least 20 paces apart.  All plants are pulled from the soil and individually examined for presence of disease.  Soil samples can also be collected to test for the presence of clubroot spores in the soil.

In reviewing the results below, please note that “Prevalence” is the % of fields having infection within the province and “Incidence” is the average number of plants showing infection within an infected field.  All these results and more information on the individual survey year and trends can be found in the Canadian Plant Disease Survey publication from the Canadian Phytopathological Society.  The reference for the individual survey and the link to the publication is referenced below each year’s table.

 

Results of the 2019 (& 2018) Canola Disease Surveys:

2019 Fields Surveyed
(165)
Sclerotinia
Blackleg
Aster
Yellows
Fusarium
Wilt
Clubroot
Alternaria
Pod Spot
Stem
Basal
Plant
Soil
% Prevalence
25
47
68
6
18
<1
-
12
Mean Severity
2
-
1.4
-
-
-
-
-
Reference: Survey of canola diseases in Manitoba in 2019. Can. Plant Dis. Surv. In press
2018 Fields Surveyed
(180)
Sclerotinia
Blackleg
Aster
Yellows
Fusarium
Wilt
Clubroot
Alternaria
Pod Spot
Stem
Basal
Plant
Soil
% Prevalence
36
54
73
5
5
0
-
16
Mean Severity
1.9
-
1.5
-
-
-
-
-
Reference: Survey of canola diseases in Manitoba in 2018. Can. Plant Dis. Surv. 99:175-178
 

For more information on diseases in canola, visit the following pages: