A SURVEY FOR BLACKLEG AND SCLEROTINIA STEM ROT ON CANOLA IN ALBERTA IN 2019

Blackleg and stem rot are commonly occurring diseases of canola (Brassica napus L.) in Alberta caused by Leptosphaeria maculans (Sowerby) P. Karst. and Sclerotinia sclerotiorum (Lib.) de Bary, respectively. Both blackleg and stem rot may be found concurrently on canola plants within the same field. A survey for these diseases was undertaken to characterize the prevalence, incidence and severity of blackleg as well as the prevalence and incidence of stem rot in Alberta canola crops in 2019. Disease levels were recorded in 261 fields and average disease levels were lower than those of previous years, presumably due, in part, to the dry conditions that prevailed in many parts of the province during the critical infection periods.