Fusarium poae and emerging mycotoxins associated with fusarium head blight in Canada.

While Fusarium graminearum Schwabe is considered the main causal agent of fusarium head blight (FHB) in cereals, Fusarium avenaceum (Fr.) Sacc., Fusarium equiseti (Corda) Sacc., Fusarium sporotrichioides Sherb., and Fusarium poae (Peck) Wollenw. are also commonly isolated from FHB-contaminated grain. These species are each capable of producing their own diverse array of mycotoxins. Globally, F. poae has been reported to produce type A and type B trichothecenes as well as beauvericin, cyclonerodiol, and enniatins, but little is known about the mycotoxigenic potential of Canadian isolates. Recent Ontario surveys suggest F. poae and F. graminearum are the main Fusaria that can be isolated from barley while F. poae is most often found contaminating oats. We initiated a study of the genetic diversity and mycotoxin production of the Canadian F. poae population. Sampling from Ontario, Quebec and Saskatchewan oat, barley, and wheat fields from 2006 to 2016 resulted in the collection of 160 monosporic F. poae isolates. Species identification was validated by sequencing the TEF1-ɑ gene. These isolates were cultured on liquid and solid growth media for metabolite profiling by UPLC-HRMS-CAD. We are surveying this collection for two unlinked mycotoxin biosynthetic gene sequences, TRI1 and TRI8, which may contribute to variations in chemotype. Phylogenetic analysis based on the TRI8 gene revealed 27 SNPs and four major groups in the Canadian population. Our goal is to define Canadian F. poae mycotoxigenic potential and explore whether genetic diversity impacts the success of F. poae on different cereal hosts.