Antonie van Leeuwenhoek

, Volume 67, Issue 4, pp 325–332 | Cite as

The fine structure of ascospore shape and development inCeratocystis fimbriata

  • C. de Beer
  • P. W. J. van Wyk
  • M. J. Wingfield
  • G. H. J. Kemp
Research Papers


Ascospore development inCeratocystis fimbriata Ell. & Halst. commenced in an eight-nucleate ascus. A single vesicle formed along the periphery of the ascus from fragments of ascospore delimiting membranes, surrounded all eight nuclei and eventually invaginated, first forming pouches with open ends, then finally enclosing each of the eight nuclei in a separate sac, thus delimiting ascospores. Pairing of the ascospores followed and brim formation occurred at the contact area between two ascospores. Osmiophilic bodies contributed to the formation of brim-like appendages by fusing to the ascospore walls. Additional brims were observed at opposite ends of the ascospores giving them a double-brimmed appearance.

Key words

Ceratocystis fimbriata C. moniliformis hat-shaped ascospores ultrastructure 



ascus vesicle


delimiting membrane


electron translucent bodies








osmiophilic bodies


plasmamembrane vesicles


primary wall


secondary wall


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Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • C. de Beer
    • 1
  • P. W. J. van Wyk
    • 2
  • M. J. Wingfield
    • 1
  • G. H. J. Kemp
    • 1
  1. 1.Department of Microbiology and BiochemistryUniversity of the Orange Free StateBloemfonteinSouth Africa
  2. 2.Department of Botany and GeneticsUniversity of the Orange Free StateBloemfonteinSouth Africa

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