Fusarium species complex causing Fusarium head blight on oat in Manitoba.

Fusarium head blight (FHB) is caused by a complex of Fusarium species in North America. Fusarium graminearum is the predominant species causing FHB on wheat. It produces several toxic secondary metabolites, among which deoxynivalenol (DON) and zearalenone (ZEN) are the most closely monitored due to their high detection rates and strong toxicity. FHB on oat was initially associated with F. graminearum in Canada. However, F. poae has become more frequently isolated in commercial oat fields in recent years. F. poae can produce a wide range of type A and B trichothecene mycotoxins as well as several non-trichothecene mycotoxins. To date, relatively little is known about the prevalence of F. poae and its impacts on the commercial oat production in western Canada. In this study, we surveyed Fusarium species infecting commercial oat fields in Manitoba from 2014 to 2016. Samples were collected from 124 commercial fields and Fusarium biomass in contaminated grains was assessed by real time qPCR using primer sets specific to Fusarium species commonly found in Western Canada. Our preliminary results indicate that Fusarium species infecting oat are, in fact, more diverse than Fusarium species infecting wheat and mycotoxins other than DON need to be considered.