Molecular genetic variation and geographical structuring in Fusarium graminearum

Summary Inter‐simple sequence repeat markers were employed to study the genetic structure of Fusarium graminearum populations collected from three Canadian provinces. Our study suggested high genetic diversity and frequent gene flow among population samples analysed. The analysis of molecular variance indicated that most of the gene diversity (91.78% to 97.23%) was distributed within populations. Frequent gene flow among the western prairie provinces and cluster analysis results indicated that the population sample from Alberta was closer to Saskatchewan than Manitoba, which could be the result of movement of the pathogen via infected grain or through wind‐borne ascospore dispersal. Analysis of multilocus associations showed that all populations were in linkage equilibrium, indicating that sexual recombination is a frequent phenomenon in F. graminearum populations from western Canada.