The Toxin-Producing Ability of Fusarium Proliferatum Strains Isolated from Grain

The widespread fungus Fusarium proliferatum can infect numerous plant species and produce a range of mycotoxins, the amount of which can vary significantly. Twelve F. proliferatum sensu lato strains isolated from six wheat, four oat, and two maize grain samples were analyzed. The strains were identified through a phylogenetic analysis of nucleotide sequences derived from gene fragments of the translation elongation factor EF-1α, β-tubulin, and RNA polymerase II second subunit. The mating types of the strain were determined by allele-specific PCR. Secondary toxic metabolite production by the strains was quantified using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). All twelve Fusarium strains formed a distinct clade alongside the F. proliferatum reference strains, thereby confirming the taxonomic identification. Only one idiomorph at the MAT locus in each F. proliferatum strain was found, indicative of heterothallic mating. The frequency of the MAT1-1 idiomorph was double that of the MAT1-2 idiomorph. The active biosynthesis of fumonisins B1 (71-6175 mg/kg), B2 (12-2661 mg/kg), and B3 (6-588 mg/kg), significant beauvericin (64-455 mg/kg), and trace amounts of moniliformin (12-6565 μg/kg) were identified across all examined F. proliferatum strains.