Changes in the range and virulence of Plasmodiophora brassicae across Canada

Figures & data

Fig. 1 The predominant pathotypes of Plasmodiophora brassicae across Canada (Williams 1966; Ayers 1972; Strelkov and Hwang 2014; Strelkov et al. 2018; this study). Pathotype nomenclature is according to Williams’ differential system (Williams 1966). ”X” pathotypes are able to overcome resistance in 45H29. The pathotypes reported to be present only after 2013 are presented in bold lettering. An Asterix indicates that the pathotype was present in a mixture of two pathotypes: see Ayers (1972)

Fig. 2 Map of canola and brassica vegetable fields in Ontario surveyed for clubroot symptoms and presence of the pathogen in soil in 2017. Fields where the pathotype (P) of P. brassicae was identified are indicated. The field where clubroot was first reported on canola in Ontario in 2016 is circled

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