Transfer of isolated nuclei into protoplasts of Trichoderma harzianum

A. Sivan, G. E. Harman, T. E. Stasz

Research output: Contribution to journalArticlepeer-review

23 Scopus citations


Protoplasts released from young hyphae of Trichoderma harzianum contained 0 to 10 nuclei per protoplast, and most (about 80%) contained from 4 to 6 nuclei. Most protoplasts were larger than 3 μm in diameter. Nuclei were isolated from protoplasts of an auxotrophic mutant of T. harzianum and transferred into protoplasts obtained from another auxotroph of the same strain. This intrastrain nuclear transfer gave rise to numerous progeny which were stable, prototrophic, and heterokaryotic. Interstrain transfers in which nuclei from a wild-type prototroph of one strain were transferred into protoplasts from a lysine-deficient auxotroph of a second strain were also done. Heterokaryotic progeny were recovered from these interstrain transfers when the regenerating protoplasts were provided with a low concentration of lysine 48 h after the initial plating. Heterokaryotic progeny contained 11 to 17% of donor-type nuclei. Progeny homokaryotic for donor-type nuclei were obtained as single-spore isolates. These homokaryotic isolates expressed the isozyme pattern and colony morphology phenotype of the nuclear donor. When regenerating protoplasts were provided with lysine 10 days after the initial plating, only a single progeny was obtained. However, single-spore subprogeny of this nuclear transfer were prototrophic and exhibited a wide range of unstable morphological phenotypes.

Original languageEnglish
Pages (from-to)2404-2409
Number of pages6
JournalApplied and Environmental Microbiology
Issue number8
StatePublished - 1 Jan 1990
Externally publishedYes

ASJC Scopus subject areas

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology
  • Ecology


Dive into the research topics of 'Transfer of isolated nuclei into protoplasts of Trichoderma harzianum'. Together they form a unique fingerprint.

Cite this