Give Clubroot the Boot with Biosecurity

By Jana Rumpel, Crop Lab and Field Technician, and Alireza Akhavan, PhD, AAg, Provincial Plant Disease Specialist, Crops and Irrigation Branch, Regina

Clubroot is a disease caused by Plasmodiophora brassicae, which is a fungal like protist. The pathogen is an obligate parasite, meaning that it cannot multiply without a live host. Clubroot affects cruciferous plants including canola causing the roots of the plant to swell and form galls and restrict the amount of water and nutrients that the plant can receive. This results in wilting, lower seed production and sometimes, premature death. To date, there are only 82 commercial fields officially documented with visible clubroot symptoms in Saskatchewan plus an additional 43 fields with the pathogen identified through DNA testing. Spores of the pathogen live in the easily transferable A horizon of soil, which is how it spreads so easily and why it is important to take biosecurity measures.

Clubroot can act as an invasive pest that travels easily, therefore, producers and other people in the agriculture industry must act by following biosecurity protocols to prevent the pathogen's further spread. Pathogen infected soil can attach to equipment, shoes and even blow freely in the wind to a new location. The best way to prevent the spread of clubroot is by avoiding the spread of already contaminated soil; the following biosecurity actions can be taken to prevent the spread of clubroot.

Remove Dirt:

• By removing soil, you are also removing clubroot spores that can be spread.
• Clean the openers on your equipment as well as knock loose dirt off your equipment, including tires and wheels and the frame. By doing these tasks, you can eliminate 90 per cent or more of the soil from your equipment, reducing the risk of clubroot spread by 90 per cent.
• Using compressed air or a pressure washer can remove up to 99 per cent of soil.

Sanitize:

• Following dirt removal, use Spray Nine, or a 2 per cent sodium hypochlorite and apply either to anything that will be going from one field to the next and has the risk of transferring clubroot.
• Two per cent sodium hypochlorite and Spray Nine are the most effective disinfectants to destroy the pathogen.
• Sanitization methods can kill almost all the resting spores. if they are left on equipment for at least 20 minutes.

Footwear and other clothing:

• Wear clean footwear that has been sanitized.
• If sanitized footwear is not an option, wear disposable boot covers and change them for each field, so you are not transferring soil from one field to another.

Create a Biosecurity Plan:

• This plan should outline guidelines and expectations for employees or others that access land to follow.
• It should include cleaning, sanitization and clothing expectations for when entering fields.

To learn more about clubroot visit our designated webpage on the disease or Canola Council of Canada website.