Differentiation of Fusarium subglutinans f. sp pini by histone gene sequence data

Fusarium subglutinans f. sp. pini (= F. circinatum) is a pathogen of pine a nd is one of eight mating populations (i.e., biological species) in the Gib berella fujikuroi species complex. This species complex includes F. thapsin um, F. moniliforme (= F. verticillioides), F. nygamai, and F. proliferatum, as well as F. subglutinans associated with sugarcane, maize, mango, and pi neapple. Differentiating these forms off. subglutinans usually requires pat hogenicity tests, which are often time consuming and inconclusive. Our obje ctive was to develop a technique to differentiate isolates of F. subglutina ns f. sp. pini from other isolates identified as F. subglutinans. We sequen ced the histone H3 gene from a representative set of Fusarium isolates. The H3 gene sequence was conserved and contained two introns in all the isolat es studied. From both the intron and the exon sequence data, we developed a PCR-restriction fragment length polymorphism technique that reliably disti nguishes F. subglutinans f. sp. pini from the other biological species in t he G. fujikuroi species complex.