Follow these steps for land that doesn’t have clubroot but is within an area with reported cases:
1. Use a resistant variety. This can keep undetected levels of clubroot from increasing to economically-significant levels. Six clubroot-resistant hybrids on the market for 2011 are D3152 from DuPont, Dekalb 73-67 and 73-77 from Monsanto, Proven 9558C from Viterra, 1960 from Canterra, and 45H29 from Pioneer Hi-Bred.
2. Use a four-year rotation. This is the preferred rotation for disease management in general.
3. Practice good sanitation. Clubroot is spread mainly by movement of soil that contains clubroot spores. Almost all new infestations begin near the field access, according to Alberta surveys, indicating that equipment contaminated with clubroot-infested soil is the key mechanism for spread of the disease. Click here for tips on how to clean machinery.
4. Control weeds. If clubroot spores are introduced, these spores have nothing to infect if host weeds and canola volunteers are controlled. With nothing to infect, clubroot cannot reproduce and increase its inoculum levels.
5. Learn to identify the disease. Roots of infected plants become malformed due to increased cell division and growth. Clubroot galls tie up nutrients, and severely infected roots can’t transport adequate water and nutrients to aboveground plant tissues. Patches of prematurely ripening canola due to clubroot infection could be confused with other diseases such as sclerotinia or blackleg. The best time to scout for clubroot symptoms on roots is late in the season, approximately two weeks before swathing, when root galls should be easy to identify. Click here for more information on how to identify clubroot.
Click here for more details on the clubroot situation in Western Canada.
Published on January 5, 2011