The toxin-producing ability of <i>Fusarium proliferatum</i> strains isolated from grain

The widespread fungus <i>Fusarium proliferatum</i> can infect numerous plant species and produce a range of mycotoxins, the amount of which can vary significantly. Twelve <i>F. proliferatum</i> 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 <i>Fusarium</i> strains formed a distinct clade alongside the <i>F. proliferatum</i> reference strains, thereby confirming the taxonomic identification. Only one idiomorph at the MAT locus in each <i>F. proliferatum</i> 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 <i>F. proliferatum</i> strains.