Discordant groupings of Fusarium spp. from sections Elegans, Liseola and Dlaminia based on ribosomal ITS1 and ITS2 sequences

Sequences of the internal transcribed spacers of the ribosomal DNA were used to compare 13 species from Fusarium sections Elegans, Liseola and Dlaminia. Two UPGMA similarity dendrograms based on the sequences of the ITS1 and ITS2 regions were discordant with each other. The dendrogram for ITS1 revealed a close similarity for most species except F. beomiforme and F. polyphialidicum. In contrast, species groupings based on the ITS2 sequences formed two main clusters that did not coincide with section boundaries. Group I consisted of Elegans (F. oxysporum), Liseola (F. sacchari var. sacchari, F. subglutinans and F. verticillioides) and Dlaminia (F. napiforme) along with Fusarium sp. isolate BBA 65467 and F. polyphialidicum. In group II Elegans (F. redolens), Liseola (F. fujikuroi and F. proliferatum) and Dlaminia (F. beomiforme, F. dlaminii and F. nygamai) clustered together. The two ITS2 groupings do not seem to accurately reflect the phylogeny of these fungi.