Development of simple sequence repeat (SSR) markers for discrimination among isolates of Fusarium proliferatum

The plant pathogen Fusarium proliferatum has a wide host range and occurs worldwide. Many isolates of the fungus produce mycotoxins in plant tissues, which, if ingested, can cause harm to animals and humans. In 2008, an outbreak of salmon blotch of onions, caused by F. proliferatum, was detected in southern Israel. The source and distribution of the fungus in Israel were unknown. Inter-simple sequence repeats (ISSR) were used to identify repetitive motifs present in seven isolates of F. proliferatum from Israel, Germany and Austria. ISSR repeat motifs were, used to develop 17 simple sequence repeat (SSR) loci. Six of these SSR markers were polymorphic in and consistently amplified from ten isolates collected in Israel, Germany, Austria and North America, from cucumber, onion, garlic, maize, and asparagus. These six polymorphic SSR alleles included 5 to 12 copies of di-, tri, and pentanucleotide motifs and yielded six to 9 alleles each. Sixteen of the SSR loci were amplified at least one of the seven Fusarium species, F. verticillioides, F. thapsinum, F. subglutinans, F. andiyazi, F. globosum, F. fujikoroi and F. oxysporum. The data demonstrate that these SSRs can be used for characterization of F. proliferatum isolates from diverse hosts and geographic locations and that they are transferable to other species of Fusarium.