Clubroot has been ravaging fields in Western Canada for almost two decades now. The soil-borne disease causes galls to form on the roots of canola plants, eventually killing them prematurely. It’s well documented in intensive clubroot zones that short canola rotations are a serious factor in aggravating the disease and creating conditions for it to thrive in, allowing new pathotypes to emerge.
The University of Alberta has identified over 43 clubroot pathotypes in Western Canada. Pathotype 3A is the most common in the region, followed closely by 3H and 3D. Clubroot is spread easily through soil movement. Root galls release spores back into the soil where they remain dormant until susceptible plants are grown again. So, if you can’t prevent it, what can you do?
Clubroot-resistant hybrids #
One of the best ways you can manage clubroot is by growing a clubroot-resistant canola hybrid. The canola industry is moving forward on standardized testing and labelling protocol for hybrids with resistance to clubroot pathotypes. This will provide growers with better information when making hybrid selections. Newer pathotypes such as 3A, 3D, and 8E are overcoming the first-generation resistance genes, which is why next-generation clubroot resistance hybrids may provide you with a better defence.
BrettYoung’s Clubroot DefendR: Broad Resistance with a Multi-Genic Approach #
Along with the identification of new pathotypes, plant breeders have been identifying and incorporating new sources of resistance into their latest canola hybrids. This includes the stacking of multiple sources of clubroot resistance in hybrids like BY 7102LL, BY 6216TF, and BY 6217TF. These hybrids have resistance to the older pathotypes that were first identified on the Prairies (2F, 3H, 5I, 6M, and 8N), plus several recently discovered pathotypes.
BrettYoung, through our primary canola genetics supplier, DL Seeds, continues to screen clubroot resistant hybrids against the most common and newly emerging clubroot pathotypes. DL Seeds is constantly working to create hybrids with resistance to the newest clubroot pathotypes, their research on the genes never ending.
Glen Hawkins, Senior Agronomist and Pulse Research Manager for DL Seeds, said together, we have a “solid next-generation resistance package” in most of our hybrids.
“At the end of the day, we’re not stopping there,” he said. “We’re always developing new genetics and new potential forms of resistance to bolster what we already have.”
Hawkins described the clubroot situation as status quo right now, with Alberta continuing to be a hotspot for the disease but noting that Manitoba is beginning to catch up. He said our first generation and next-generation clubroot resistant products are doing what they’re supposed to, with both having multi-pathotype specificity.
“The gene we insert,” he started, “will have full or partial resistance to a number of different pathotypes.”
Clubroot Management Practices #
The Canola Council of Canada has a list of recommendations to manage the spread of clubroot spores by focusing on keeping them low and local.
Keep it LOW
- Scout frequently. Scout diligently and pull plants to catch early infestation, especially in high traffic or moisture prone areas.
- Crop rotation. Maintain a minimum two-year break between canola crops.
- Grow clubroot-resistant hybrids on every acre as part of an integrated pest management strategy.
- Control weeds. Control host brassicae weeds to minimize gall formation and spore release.
Keep it LOCAL
- Reduce tillage to reduce the spread of soil and pathogens within it and between fields.
- Biosecurity. Prevent introduction and the spread of spores by using proper sanitation practices.
- Utilize patch management in small areas with clubroot symptoms.
Growers in Manitoba, Saskatchewan, and other areas not impacted by clubroot pathotype 3A can prevent the accumulation of spores for as long as possible by using resistant hybrids. Choose BrettYoung’s Clubroot DefendR hybrids for areas where incidence of resistance breakdown is suspected.