Canola Watch quiz – Clubroot

Test your clubroot skills with these four questions.

The International Clubroot Workshop is in Edmonton August 7-9. Anyone with an interest in clubroot management and research is welcome, including farmers, agronomists and municipal ag staff. The workshop attracts researchers from around the world to discuss the latest discoveries and practical in-field management applications. Click here for conference information and registration.

On that theme, here are a few questions related to clubroot that could help with management decisions.

1. Michael Harding with Alberta Agriculture & Forestry recently compared 10 disinfectant solutions to see which is best to kill clubroot spores on machinery, tires and boots, etc. Four of those 10 products achieved 95% inactivation of clubroot resting spore viability, qualifying them as effective. Of those four, which did he conclude was the most practical choice?
2. Here is a weed with a large clubroot gall. What weed species is it?

3. How quickly after seedling emergence can galls start to form on susceptible plants?
4. Liming to increase soil pH can help in clubroot management. An Alberta study on two clubroot-infested fields with low pH shows that applying lime to increase pH to a neutral level will reduce clubroot and increase yield. Recent greenhouse trials show that clubroot galls will grow prolifically in solutions with pH of 6.5 but not in solutions with pH of 7.3. Approximately how much lime per acre would be required to move pH from 6.5 to 7.3?