Introduction to Fungi, Third Edition

POLYPOROID CLADE
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Fig19.24 Trametes versicolor. (a) Vertical section through a basidiocarp. (b) Group of hyphae teased from the growing margin.Only
generative and skeletal hyphae are present here. In the adult flesh, binding hyphae are also present (see Fig.19.3). (c) Transverse
section across a pore showing the hymenium. (d) Longitudinal section of part of a dissepiment.The tissue contains only generative
and skeletal hyphae. (b d) to same scale.
Piptoporus
Piptoporus betulinus basidiocarps are a common
sight on dead and dying birch trees (Fig. 19.23d).
The fungus is probably a wound parasite, its
basidiospores entering and germinating where
branches have broken off. Infected trees show
a brown-rot of the heart wood which first
undergoes cubical cracking and later disintegrates
as a powder. Although the brown-rot
indicates cellulose decay, there is also evidence