New sclerotinia tool helps growers assess disease risk and severity

Growers and agronomists looking for help in making sclerotinia spray decisions this summer will have access to a new online tool from the Canola Council of Canada. Available at CanolaCalculator.ca, the sclerotinia risk assessment tool offers both a recommendation about whether or not to spray a canola crop (at 20-50 per cent flower) based on several inputs from the user, along with an opportunity to assess the spray decision by rating sclerotinia severity at maturity (30-60 per cent seed colour change).

The second part of the tool is an economic calculator to provide an estimated return on a fungicide application based on different scenarios. These include percent of infection, fungicide cost, expected yield and market price.

Sclerotinia stem rot infection often starts when spore-infested petals drop onto leaves and create lesions.

“These new tools are designed to help growers and agronomists make timely, informed decisions on whether a foliar fungicide application is advised,” said Chris Manchur, CCC agronomy specialist and lead on sclerotinia stem rot. “Farmers have a lot of choices to make throughout the growing season. It’s very exciting to put this new technology in their hands to help simplify decision making and assess potential impacts on productivity and profitability.”

Sclerotinia stem rot is one of the most economically significant canola diseases in Canada. Caused by the fungus Sclerotinia sclerotiorum, the disease is heavily influenced by environmental conditions leading up to and during the flowering period of canola. Assessing the environment can make it difficult to predict outbreaks and make the decision to spray. That is where the tool comes in.

The tool also includes a helpful resource library which hosts images, videos and other educational materials, serving as a valuable knowledge hub supporting growers and agronomists in sclerotinia management.

These tools were built following three years of collaboration with Agriculture and Agri-Food Canada and extensive testing with agronomist partners and are an evolution of the sclerotinia stem rot checklist that growers and agronomists have relied on for years. The project was funded in part by the Government of Canada under the previous Canadian Agricultural Partnership - AgriScience Program, along with support from Alberta Canola, SaskCanola and Manitoba Canola Growers.