Drechslera

McGinnis et al. (1986b) have reviewed the isolates from human and animal disease purported to be Drechslera or Helminthosporium and concluded that all pathogenic isolates examined actually belong to the genera Bipolaris or Exserohilum.

Conidia of Drechsler spp

Conidia of Drechsler spp.

RG-1 organism.

Morphological description: 
Colonies are fast growing, suede-like to downy, brown to blackish brown with a black reverse. Conidia are pale to dark brown, usually cylindrical or subcylindrical, straight, smooth-walled, and are formed apically through a pore (poroconidia) in a sympodially elongating, geniculate conidiophore. Conidia are transversely septate (phragmoconidia), with the septum delimiting the basal cell formed first during conidium maturation. Germinating is from any or all cells and the hilum is not protuberant.

Key features: 
Dematiaceous hyphomycete producing sympodial, pale brown, cylindrical or subcylindrical, transversely septate poroconidia.

References: 

  • de Hoog, G.S., Guarro, J., Gene, J., et al. (2015) Atlas of Clinical Fungi (Version 4.1.2). Centraalbureau voor Schimmelcultures, Utrecht, The Netherlands.
  • Domsch, K.H., Gams, W. and Anderson, T.H. (2007) Compendium of soil fungi. Second Edition, IHW-Verlag, Germany.
  • Ellis, M.B. (1971) Dematiaceous hyphomycetes. Commonwealth Mycological Institute, Kew, Surrey, England.
  • Ellis, M.B. (1976) More dematiaceous hyphomycetes. Commonwealth Mycological Institute, Kew, Surrey, England.
  • Kidd, S., Halliday, C., Ellis, D. (2023) Descriptions of Medical Fungi (4th edition). CABI.
  • McGinnis, M.R., Rinaldi, M.G. and Winn, R.E. (1986b) Emerging agents of phaeohyphomycosis: pathogenic species of Bipolaris and Exserohilum. Journal of Clinical Microbiology, 24, 250-259.
  • McGinnis, M.R. (1980) Laboratory handbook of medical mycology. Academic Press, New York.
  • Sivanesan, A. (1987) Graminicolous species of Bipolaris, Curvularia, Drechslera, Exserohilum and their teleomorphs, 261pp. Mycological Paper No. 158. CAB International, Wallingford, U.K.
  • Rippon, J.W. (1988) Medical mycology: the pathogenic fungi and the pathogenic actinomycetes, 3rd edition. W,B. Saunders Co, Philadelphia, USA.

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