Transformation de la matière organique végétale sous l'action du termite <i>Macrotermes mülleri</i> (Sjöstedt) et de son champignon symbiotique

Abstract

The fungus Termitomyces sp., an exosymbiont of the termite Macrotermes mülleri, can perforate the pectin–cellulose walls of the vegetative cells present in the fungal comb in such a way as to get near the dark pigments (polyphenol proteins). This fungus, through cellulolytic, pectinolytic, and perhaps ligninolytic activities, extensively degraded these brown substances. Subsequently bacterial and enzymatic degradation of the different plant materials continued in the digestive tract of the termite and its endosymbionts. The faeces deposited in the nest and on the ground were essentially composed of organic granules and organo–mineral microaggregates. These microaggregates were produced during intestinal transit by the adsorption of clay particles onto the biodegraded organic matter. The weak organo–mineral bonds suggest that the organic residue will be easily mineralized.