Fusarium cerealis, a single phylogenetic species recovered annually from maize in Belgium and producing a wide range of mycotoxins

Fusarium cerealis is a ubiquitous fungal species often associated with Fusarium ear and stalk rot. A five-year epidemiological survey showed the systematic occurrence of this species in Belgian maize fields, as well as its high incidence at the end of the growing season under favorable infection conditions. A set of 1070 F. cerealis isolates was collected from maize in Belgium between 2005 and 2012 and representative strains were examined for their distribution in the field, mycotoxin production and evolutionary history. Screening of eighteen different Fusarium mycotoxins confirmed the capacity of F. cerealis to produce fusarin C, nivalenol, fusarenone X, zearalenone, alpha- and beta-zearalenol. Surprisingly, the production of deoxynivalenol, 3-acetyl-deoxynivalenol, T2 toxin and beauvericin was also observed for this species. Phylogenetic analyses of reductase and elongation factor 1-α gene sequence data clustered F. cerealis and its sister species F. culmorum in two well-supported separated groups. Fusarium cerealis behaves as a genetically recombining single phylogenetic species, with no distinct lineage development. In addition, the two mating type MAT idiomorphs occurred approximately in equal proportions within the Belgian population of F. cerealis. This further strengthens the hypothesis that sexual reproduction might be common in this species, although sexual stage has not yet been reported.