Diouf Michel, Brauman Alain, Mora Philippe, Miambi Edouard, Rouland Lefevre Corinne. (2006). Modification of soil fungal communities in crop sheetings of fungus-growing termites and its effects on soil functioning (Isoptera : Termitidae). Sociobiology, 47 (2), p. 353-371. ISSN 0361-6525.
Titre du document
Modification of soil fungal communities in crop sheetings of fungus-growing termites and its effects on soil functioning (Isoptera : Termitidae)
Sociobiology, 2006,
47 (2), p. 353-371 ISSN 0361-6525
Previous studies have already established that the soil fungal communities in the crop sheetings of fungus-growing termites are modified. This study investigated the potential impact of such modifications of fungal communities on soil functioning combining two approaches. The first was a comparison of the metabolic profiles of the fungal communities colonizing the sheetings of three fungus-growing termites with those of the surrounding soil by cultivation on several substrates. The number of cultured fungi totaled across all substrates was at least 16 times higher in all the sheetings than in the control soil. Moreover, on all substrates but one (cellulose), the number of cultured fungi was always higher in the sheetings than in the soil. When the relative numbers of cultured fungi on each substrate were compared with the total cultivable community, it appeared that the fungal communities in the shectings were characterized by a high relative abundance of proteolytic fungi (up to 80% in the sheetings of A. guineensis) whereas, in the soil, the fungi that grew on the different substrates were more homogeneous. The second approach compared the metabolic capacities of several fungal strains chosen from the original samples on the basis of their representativeness and specificity. 'Their capacities to mineralize the complex components of the soil plant matter were compared. The results are discussed in relation to the taxa identified using the ITS (Internal Transcribed Spacer) sequence. On the whole, the predominant fungi in soils, in particular in topsoil, are likely to be highly competitive strains able to metabolize a wide range of substrates. The populations in the termite structures, however, are more diversified in terms of number of morphotypes isolated with metabolic capacities that are more limited for each individual morphotype and shared across several taxa.
