Taxonomy and phylogeny of Gliocladium analysed from nuclear large subunit ribosomal DNA sequences

Abstract

The phylogenetic distribution of Gliocladium within the Hypocreales was investigated by parsimony analysis of partial sequences from the nuclear large subunit ribosomal DNA (28S rDNA). Two principal monophyletic groups were resolved that included species with anamorphs classified in Gliocladium. The first clade includes elements of the genera Hypocrea (H. gelatinosa, H. lutea) plus Trichoderma, Hypocrea pallida, Hypomyces and Sphaerostilbella, which are each shown to be monophyletic but whose sister group relationships are unresolved with the present data set. Gliocladium anamorphs in this clade include Gliocladium penicillioides, the type species of Gliocladium and anamorph of Sphaerostilbella aureonitens, and Trichoderma virens (= G. virens) which is a member of the clade containing Hypocrea and Trichoderma. A second clade, consisting of species with pallid perithecia, is grouped around Nectria ochroleuca, whose anamorph is Gliocladium roseum. Other species in this clade having Gliocladium-like anamorphs are Nectriopsis sporangiicola and Roumegueriella rufula. The species of Nectria represented in this study are polyphyletic and resolved as four separate groups: (1) N. cinnabarina the type species, (2) three species with Fusarium anamorphs including N. albosuccinea, N. haematococca and Gibberella fujikoroi, (3) N. purtonii a species whose anamorph is classified in Fusarium sect. Eupionnotes, and (4) N. ochroleuca, which is representative of species with pallid perithecia. The results indicate that Gliocladium is polyphyletic and that G. penicillioides, G. roseum, and Trichoderma virens (= G. virens), are generically distinct.