Canadian Forest Service Publications

Types of osmiophilic inclusions in cells of Ceratocystis ulmi. 1977. Chamberland, H.; Ouellette, G.B. Can. J. Bot. 55(6): 695-710.

Year: 1977

Issued by: Laurentian Forestry Centre

Catalog ID: 16673

Language: English

Availability: PDF (request by e-mail)

Mark record


The presence of osmiophilic inclusions of various shapes and sizes and of more or less homogeneous texture has been reported in a number of fungi (Garrison and Boyd 1973; Gunasekaran et al. 1973; Heintz and Niederpruem 1971; Shearer and Motta 1973; Zaki et al. 1972). Various roles have been given to these inclusions, and various hypotheses mentioned concerning their nature. According to one of these hypotheses, based on observations of Penicillium marneffei, such inclusions would be linked to the state of virulence of this pathogen.

Some of the osmiophilic inclusions observed by Harris and Taber (1973) in Ceratocystis ulmi seem to be analogous in texture to the substance observed in association with cell wall breakdown in American elm (Ulmus Americana L.) xylem tissues infected by this pathogen (Ouellette 1977). Harris and Taber mention that these inclusions may be related to lipidic bodies, however without giving further details on their formation.

An attempt is made in the present work to further characterize these inclusions in C. ulmi and to determine to what extent they can be related to the free osmiophilic substances associated with host tissue disturbances. Other observations on the general ultrastructural characteristics of the fungus and also using high resolution radioautography, are presented in another publication (Chamberland and Ouellette 1977).