Disentangling the Trichoderma viridescens complex
- Author: mycolabadmin
- 2013-08-19
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Summary
This research focused on distinguishing different species within a group of closely related fungi called Trichoderma viridescens. Using genetic analysis and detailed microscopic examination, the researchers identified 13 distinct species that look very similar but are genetically different. This work helps mycologists and other scientists accurately identify these fungi, which is important for both research and practical applications.
Impacts on everyday life:
– Improves our ability to correctly identify fungi that may be beneficial or harmful in agriculture and industry
– Helps understand biodiversity and evolution of fungi in natural environments
– Provides tools for quality control in biological products that use these fungi
– Enables better monitoring of fungal populations in environmental and clinical settings
– Aids in developing targeted applications of beneficial Trichoderma species in agriculture and biotechnology
Background
Trichoderma viridescens is recognized as a species complex with varying and often subtle morphological differences that do not always correlate with phylogenetic inferences. Previous studies focused mainly on distinguishing T. viride from T. viridescens based on asexual morph morphology, while the complex structure of various subclades within the monophyletic T. viridescens complex remained taxonomically unresolved.
Objective
To analyze and resolve the taxonomy of the Trichoderma viridescens species complex using multigene phylogenetic analysis and detailed morphological characterization.
Results
The analysis revealed 13 phylogenetic species within the T. viridescens complex with little or no phenotypic differentiation. The study clarified the typification of T. viridescens s.str. and replaced Hypocrea viridescens with T. paraviridescens. Ten new species were formally described: T. olivascens, T. viridarium, T. virilente, T. trixiae, T. viridialbum, T. appalachiense, T. neosinense, T. composticola, T. nothescens and T. sempervirentis. Several species produce yellow diffusing pigment on cornmeal dextrose agar after storage at 15°C, while T. olivascens is characterized by forming an olivaceous pigment.
Conclusion
The T. viridescens complex comprises 13 distinct species that are difficult to delimit based on morphological characters alone. While there are differences in pigment formation, growth rates, conidial shape and conidiophore structure, phenotypic characters overlap significantly. Reliable species identification requires molecular data, particularly tef1 sequences, ideally combined with rpb2 and/or acl1 sequences.
- Published in:Persoonia : Molecular Phylogeny and Evolution of Fungi,
- Study Type:Taxonomic Study,
- Source: 10.3767/003158513X672234