Fusarium subglutinans and F. temperatum are common maize pathogens that produce mycotoxins and cause plant disease. F. subglutinans sensu lato in 2011 has been divided into F. temperatum sp. nov. and F. subglutinans sensu stricto, showing different phylogeny and beauvericin production, even though the presence of beauvericin (bea) genes in both species. Genetic differences in bea gene cluster could be related to different ability to produce BEA by these two closely related spe-cies, and related genetic interspecies variability could provide insights into the evolutionary pro-cesses involved in their separation into different species. Previously, has been highlighted that bea1, which encodes the NRPS22, the nonribosomal peptide synthase responsible for synthesizing the beauvericin backbone, in F. subglutinans, compared to F. temperatum, is affected by polymor-phisms, presumably related to its inability to produce beauvericin, in despite of the presence of re-lated 4 biosynthetic genes. In this work, nucleotide variability in tef1a has been exploited to design species-specific PCR primers useful for correct species identification; the 3 polymorphisms, previ-ously described in bea1 gene, were searched in a set of strains (48 F. subglutinans and 44 F. temperatum), collected from worldwide maize (Argentina, Austria, Belgium, Germany, Iowa, Italy, Po-land, Serbia, Slovakia, Switzerland, Netherland). The most frequent polymorphism detected was the SNP528. Considering that SNP frequency is proportional to the recombination frequency, the high frequence of SNP528 leads to suppose that mutations occurred after speciation divergence between F. subglutinans and F. temperatum.
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