Canada
April 22, 2014

New data indicates some forms of clubroot resistance are no longer functioning well against a possible new clubroot pathotype in the Edmonton region.

Dr. Stephen Strelkov at the University of Alberta has investigated samples collected from several fields and verified higher levels of infection than expected in some clubroot resistant varieties. Further studies are underway to verify the true virulence of these clubroot strains.

“Current research indicates that the concern is limited to very few fields and patches within those fields,” says Curtis Rempel, Vice President of Crop Production and Innovation with the Canola Council of Canada (CCC). “Clubroot resistance is expected to be functional in the vast majority of acres this year, but attention needs to be paid to prevent this situation from expanding.”

While it is too early to make specific variety recommendations, the CCC advises that canola growers and agronomists scout their clubroot resistant varieties this summer with extra effort and vigilance. “This is very important in light of the potential for a new pathotype capable of overcoming the excellent resistance currently available in Western Canada,” says Rempel.

In order to protect this valuable genetic trait, the CCC will be working collaboratively throughout the canola value chain to learn more about this potential new pathotype and help prevent its buildup and movement. Factors that contribute to this risk are:

• Canola rotations with less than a two year break
• Fields that are known already to have high clubroot inoculum
• Fields that are not scouted for clubroot regularly
• Planting the same resistant canola variety in that rotation
• Any tillage that is more than zero till
• Operations that do not limit soil movement between fields. Keep your soil at home.

Clubroot is a serious soil-borne disease caused by the pathogen Plasmodiophora brassicae. It lowers the bottom line for canola growers each year. The disease has been advancing through Alberta at a fairly steady 20 to 25 km per year, and has been detected at low levels in Manitoba and Saskatchewan. Visit www.clubroot.ca to learn more about clubroot best management practices and stewardship of resistant varieties.

The Canola Council of Canada is a full value chain organization representing canola growers, value added processors, life science companies and exporters.
 

Website: http://www.canola-council.org

Published: April 22, 2014