Managing Blackleg in Canola

Blackleg is a fungal disease in canola that can cause yield and quality losses, impact profitability and may create a market risk. Effective blackleg management supports on-farm profitability and protects Canada’s reputation as a trusted supplier of high-quality canola.  

To manage blackleg risk and preserve the effectiveness of genetic resistance, growers are encouraged to use an integrated blackleg management strategy rather than relying on a single tool. 

Best practices for integrated blackleg management 

Crop rotation 

The blackleg pathogen overwinters on infected canola residue. Maintain a break between canola crops to allow residue to decompose and reduce disease carryover. 

• A minimum two‑year break between canola crops is recommended 
• Longer rotations further reduce pathogen pressure 

Resistant varieties 

Plant canola varieties with blackleg resistance that is effective in your field. 

• Select varieties rated R (resistant) 
• Rotate varieties over time to introduce different blackleg resistance genes and sources to the field 
• Use blackleg race identification testing to identify predominant races in the field and help match appropriate major gene resistance