By Venkata Chapara, Ph.D.
Clubroot disease on canola is caused by Plasmodiophora brassicae, a soil-borne pathogen that moves from field to field on both agricultural and non-agricultural equipment. In simple words, it moves from whatever moves the soil. With an objective to determine the extent of disease spread in North Dakota, clubroot incidence and prevalence has been monitored in annual surveys for six years by examining canola roots for clubs/galls. These surveys have been funded by the Northern Canola Growers Association, Northern Canola Research Program (USDA/NIFA), SBARE and NDCP Product Harmonization Board.
Results indicate that clubroot on canola is so far endemic to Cavalier County since its first identification in North Dakota via visual galls on roots. The highest number of canola fields with clubroot incidence was recorded in 2018 (31% of the canola fields that were surveyed were found with galls on roots) and the lowest (5%) in 2021 (Figure 1).