The impact of termite sheetings age on their fungal communities

In previous studies, we have shown that fungal communities in soil are quantitatively and qualitatively modified when termite sheetings are constructed, but the reasons for these changes are unknown. In this work we described the succession of fungal communities in the sheetings of three fungus-growing termite species by combining cultivation techniques and culture-independent methods specially DNA extraction, PCR and denaturing gradient gel electrophoresis (DGGE). We also estimated the abundance of fungi by using plate-count technique. The fungal communities of these sheetings were sampled at different ages. The potential functions of fungal communities was assessed by their capabilities of degrading different substrates including proteins, polysaccharides and tannins. Significant differences were found between the fungal communities of termite sheetings and those of surrounding soil. These differences were observed at quantitative, qualitative and functional level as well and were marked particularly in the fresh sheetings of termites. The characteristics of fungal communities of the surrounding soil were quite similar with those observed in the old sheetings of termites. These results show that the fungal communities are modified at once in freshly built sheetings, rather than by a progressive succession, as had been expected.