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Wednesday, 1 May 2024

Field Bio-Sanitation Protocol and Mitigating Transmission of Soil-borne Diseases

Clubroot is a soil-borne disease of canola and other cruciferous plants of the Brassicaceae family which is caused by a pathogen called Plasmodiophora brassicae. Clubroot is spread when infested soil is transported by vehicles and farm machinery or though wind and water erosion. Roots of infected plants have a club-like appearance (Fig. 1). Above-ground symptoms vary depending on the growth stage at time of infection. Common symptoms include wilting, stunting, yellowing, and premature ripening. Above-ground symptoms are similar to common canola disorders thus it is important to carefully dig up suspect plants and inspect the roots.


Figure 1. Characteristic clubroot galls on an infested canola plant. 
Photo: (LL, ND, CC BY-SA 2.0)

The distribution of clubroot in the Peace River region has increased since first appearing in Big Lakes County (August 2017) and now includes additional sites in northwestern Alberta:

Back in 2004, the Integrated Pest Management Program (IPM) implemented biosanitation protocols including use of tyvek booties and sterilization of all field equipment. From 2017-2018, field sanitation involved the use of Virkon and bleach and, since 2019, involved bleach only. As of May 2023, our biosecurity protocol includes:

Figure 2. Washing AAFC vehicle at the commercial to remove soil after a long day of fieldwork. 
Photo: Maddy Jones-AAFC Beaverlodge.


Figure 3. Floor mats are hung and sterilized with bleach while at the commercial car wash. 
Photo: Maddy Jones-AAFC Beaverlodge.


  • Wearing impermeable shoes while operating and exiting vehicle. These shoes are sterilized each day.
  • Sterilizing impermeable boots using bleach both AT and BETWEEN each field (Fig. 4). 
  • Wearing disposable booties are over sterilized impermeable boots prior to entering field or pull-in (Fig. 5).
Figure 4. Impermeable boots are placed into bins containing a bleach solution while traveling between field sites. Photo: Maddy Jones AAFC-Beaverlodge.


Figure 5. Disposable booties are donned over sterilized impermeable boots prior to field entry at each site. 
Photo: Maddy Jones AAFC-Beaverlodge.


  • Parking AAFC vehicles on the side of the road - we NEVER drive into a field!
  • Using sodium hypochlorite or bleach (2%) to sterilize vehicle tires, wheels, and wheel-wells both AT and BETWEEN each field (Fig. 6). 
Figure 6. Wheel-wells and tires are sterilized upon arrival to each field site using a bleach solution. 
Photo: Maddy Jones AAFC-Beaverlodge.

  • Soaking all field equipment that contacts soil (e.g., spades, trowels, soil core samplers) in bleach after use in each field. 
  • Bagging and sterilizing all booties using an autoclave (employs high temperature and pressure).
  • Carrying multiples of small field equipment to allow for soaking in bleach and/or sterilization using an autoclave.
  • Maintaining a log of all visits and all field sanitation protocols implemented.

Please contact us if you have questions or concerns! If you wish to personally see our sanitization efforts in action, we can arrange it! You can contact us by emailing Shelby Dufton.

We thank growers for their continued support of field research by way of granting permission for our staff to access land to collect data. Out staff continue to do our utmost to ensure every field remains protected. 

Post prepared by Madysen Jones