By Barbara Ziesman, PhD, AAG, Provincial Specialist, Plant Disease
Over the past few years, clubroot has received a lot of publicity in Saskatchewan. This is due to an increased number of commercial fields confirmed to have clubroot in 2017 and 2018 (43 fields total), the yield loss potential associated with the disease, and the fact that it is still a relatively new disease in the province. Being a new disease with a relatively limited distribution is advantageous because it means that we have an opportunity to take action to minimize the spread of the disease and its impact on the Saskatchewan canola industry. To achieve this common goal, it is important that we all work together.
The 2019 clubroot survey is a good example of teamwork toward achieving a common goal. The survey will be conducted through a collaboration between the Saskatchewan Ministry of Agriculture, SaskCanola, the Saskatchewan Association of rural Municipalities (SARM) Plant Health Officers and the Saskatchewan Crop Insurance Corporation (SCIC). It will address three main objectives.
- To better understand the spread of clubroot within areas where it has already been found and that have a higher clubroot risk (yellow area on map).
- To survey areas of the province that were not included in the 2018 clubroot survey (light and dark grey areas on map).
- To encourage producers to monitor for the clubroot pathogen on their own farms through a voluntary soil testing program.
The in-field component of the 2019 clubroot survey will include 1,800 commercial canola fields and will take place from late July to October. Approximately 600 canola fields will be surveyed in areas where clubroot and or the clubroot pathogen are known to occur to better understand the impact of clubroot in the highest-risk areas of the province (objective 1). The remaining 1,200 canola fields will be located in areas of the province that were not surveyed in 2018 (objective 2). To account for the intensity of canola production and clubroot risk, two different sampling intensities will be utilized as part of objective 2. A grid sample approach, with one field sample in every township, will be implemented in areas with higher canola production and/or an increased clubroot risk (dark grey), and one to two fields will be surveyed in each Rural Municipality (RM) in areas with lower canola production and a reduced clubroot risk (light grey).
In each field, surveyors will examine the plant for clubroot galls and collect soil samples for DNA-based testing to detect the clubroot pathogen at low levels. SARM Plant Health Officers will lead the majority of the in-field surveillance with support from Ministry and SCIC staff. All surveyors will be appointed as Pest Control Officers under The Pest Control Act and will follow strict biosecurity protocols to prevent the spread of clubroot or other crop pests.
When clubroot and/or the clubroot pathogen are confirmed to be present in the field (either through the in-field survey or through the voluntary soil testing program), the producer will be contacted and encouraged to manage the clubroot-infested field using an integrated approach as outlined in the Saskatchewan Clubroot Management Plan. The specific location of the field will be kept confidential and will only be shared with the appropriate RM if they have a clubroot bylaw enacted. The general location of the field (to an RM level) will be used to raise awareness of the presence of clubroot and to update the Saskatchewan Clubroot Distribution Map.
The Saskatchewan Clubroot Distribution Map is an important tool that can be used to estimate regional clubroot risk. To ensure that it is as accurate and robust as possible, we encourage producers and agrologists to report new findings of clubroot (even to a township or RM level) to the Ministry. This information will be used to monitor the distribution of clubroot in the province and to update the Saskatchewan Clubroot Distribution Map. Having a strong understanding of the distribution of clubroot is important to guide research efforts, monitor the disease severity and detect the presence of aggressive pathotypes that can overcome resistant clubroot varieties.
If you would like to report a new clubroot finding, please contact your local Crops Extension Specialist, Barb Ziesman (Provincial Specialist, Plant Disease or Matthew Bernard Provincial Specialist, Oilseed Crops.