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Updated: Jun 21, 2026
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Published on: October 20, 2023
Sexual development in the industrial workhorse Trichoderma reesei
Verena Seidl1, Christian Seibel, Christian P Kubicek
1Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Getreidemarkt 9/166-5, 1060 Vienna, Austria.
Summary
Researchers discovered that the industrially important fungus Trichoderma reesei is heterothallic, not asexual. This finding enables sexual reproduction, paving the way for improved enzyme and biofuel production.
Area of Science:
- Mycology
- Biotechnology
- Genetics
Background:
- Filamentous fungi are vital for industrial production of chemicals, enzymes, and antibiotics.
- Current industrial strains are primarily improved through classical mutagenesis.
- Sexual reproduction offers significant advantages for strain improvement but was thought to be absent in many industrially relevant species.
Purpose of the Study:
- To investigate the mating system of the filamentous fungus Trichoderma reesei.
- To identify mating type loci (MAT-loci) in T. reesei and its sexual morph, Hypocrea jecorina.
- To induce and analyze sexual reproduction in T. reesei for biotechnological applications.
Main Methods:
- Identification of the MAT1-2 mating type locus in T. reesei QM6a.
- Screening natural isolates of H. jecorina for the complementary MAT1-1 mating type locus.
- Induction of sexual reproduction and analysis of resulting ascospores.
Main Results:
- T. reesei QM6a possesses the MAT1-2 mating type locus.
- The complementary MAT1-1 mating type locus was identified in natural H. jecorina isolates, confirming T. reesei as heterothallic.
- Sexual reproduction was successfully induced in T. reesei QM6a, yielding mature ascospores.
Conclusions:
- Trichoderma reesei, previously considered asexual, is confirmed to be heterothallic.
- The ability to induce sexual reproduction in T. reesei provides a powerful new tool for industrial strain improvement.
- This breakthrough has implications for enhancing enzyme and biofuel production and for research in other Trichoderma species.
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