Genetic evidence for a recent geographic expansion of 15-acetyldeoxynivalenol chemotypes of Fusarium graminearum in Canada

The genetic structure of 15-acetyldeoxynivalenol (15-ADON) chemotypes of Fusarium graminearum populations collected from Canada was examined using restriction length fragment polymorphism and inter simple sequence repeat molecular markers. The genetic analysis revealed that 15-ADON producing F. graminearum populations from different provinces of Canada are genetically homogeneous. Mismatch distribution analysis was used to examine the evolutionary factors leading to genetic homogeneity among populations. The results of mismatch distributions showed evidence of a recent burst in population growth and demographic expansion across Canada. These results suggested that vigilant monitoring of trends of population growth of F. graminearum in Canada may be useful for management of this fungal pathogen.