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Molecular phylogeny and species delimitation in the section Longibrachiatum of Trichoderma.

ABSTRACT: The phylogenetically most derived group of the genus Trichoderma - section Longibrachiatum, includes some of the most intensively studied species, such as the industrial cellulase producer T. reesei (teleomorph Hypocrea jecorina), or the facultative opportunistic human pathogens T. longibrachiatum and H. orientalis. At the same time, the phylogeny of this clade is only poorly understood. Here we used a collection of 112 strains representing all currently recognized species and isolates that were tentatively identified as members of the group, to analyze species diversity and molecular evolution. Bayesian phylogenetic analyses based on several unlinked loci in individual and concatenated datasets confirmed 13 previously described species and 3 previously recognized phylogenetic species all of which were not yet described formally. When the genealogical concordance criterion, the K/? method and comparison of frequencies of pairwise nucleotide differences were applied to the data sample, 10 additional new phylogenetic species were recognized, seven of which consisted only of a single lineage. Our analysis thus identifies 26 putative species in section Longibrachiatum, what doubles the currently estimated taxonomic diversity of the group, and illustrates the power of combining genealogical concordance and population genetic analysis for dissecting species in a recently diverged group of fungal species.

SUBMITTER: Druzhinina IS

PROVIDER: S-EPMC3350856 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Molecular phylogeny and species delimitation in the section Longibrachiatum of Trichoderma.

Druzhinina Irina S IS Komoń-Zelazowska Monika M Ismaiel Adnan A Jaklitsch Walter W Mullaw Temesgen T Samuels Gary J GJ Kubicek Christian P CP

Fungal genetics and biology : FG & B 20120301 5

The phylogenetically most derived group of the genus Trichoderma - section Longibrachiatum, includes some of the most intensively studied species, such as the industrial cellulase producer T. reesei (teleomorph Hypocrea jecorina), or the facultative opportunistic human pathogens T. longibrachiatum and H. orientalis. At the same time, the phylogeny of this clade is only poorly understood. Here we used a collection of 112 strains representing all currently recognized species and isolates that were ...[more]

PMID: 22405896

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Dataset Information

Molecular phylogeny and species delimitation in the section Longibrachiatum of Trichoderma.

Publications

Molecular phylogeny and species delimitation in the section Longibrachiatum of Trichoderma.

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