This forecasting program has been developed by the North Dakota State University Canola Pathology program with support from the Sclerotinia Initiative, the Northern Canola Growers Association, and the Minnesota Canola Council. While the information presented by this program is based on data generated through extensive research, it is only intended to serve as a guide for growers.
This forecasting program has two components, a general risk map and a risk calculator. The general risk map uses weather information to estimate risk of disease development throughout the canola growing areas of the state. This map is updated twice every week starting in mid June and continuing during the canola flowering period. The risk calculator combines information on cultural practices and the field past history of Sclerotinia with weather information retrieved from the nearest NDAWN weather station to estimate the risk of disease development for a specific field. To access the risk calculator visitors are asked to set an account and to provide information pertinent to the field of their interest.
Be on the lookout for early blackleg symptoms
Yield losses caused by blackleg are typically greater when infections take place before the plants reach the four-to-sixth leaf growth stage. Growers should scout their fields for symptoms of early infections on cotyledon leaves starting two weeks after planting. These lesions may be irregular in shape and have a light brown color. Numerous pycnidia which look like tiny grain of black pepper may be produced in the dead tissues especially if humid conditions prevail for several days. As the plants continue developing, symptoms on true leaves may also appear. Their presence in plants with less than four true leaves is an indication that blackleg may be a problem that requires fungicide applications. A list of fungicides registered for use in canola against blackleg can be found in NDSU extension publication 2019 ND Field Crop Plant Disease Management Guide.
Sclerotinia Risk Maps for 2020
Sclerotinia Risk Maps will be produced starting on June 19, 2020 and through the end of July 2020. The maps will be available through this website as well as through the Northern Canola Growers Association website, and the NDSU Canola Doctor application.