A breakthrough for wood decay fungi

Abstract

An overall explanation for the mechanisms by which decay fungi invade and degrade wood in standing trees is still incomplete. The relative aggressiveness of these fungi seems to be a function of their ability to degrade both lignin and polyphenolic compounds formed in response to wounding. The fact that less-invasive fungi appear to avoid polyphenolic deposits by tunnelling into the cellulose-rich regions of the wood cell wall and do not display an ability to penetrate through the lignin-rich middle lamella adds weight to this view. Furthermore, the living nature of the substrate and the host response to fungal invasion are necessary considerations, particularly with respect to the influence of seasonal changes that affect the carbohydrate reserves and moisture content of the wood. The work of Schwarze and Baum provides further evidence to suggest that there is much greater diversity in the way different decay fungi challenge their hosts and substrates. The terms brown rot, white rot and soft rot may not be obsolete, but rigid definitions for fungi that are placed into these categories may be less appropriate than thought previously.