Diversity of community soil DNA and bacteria in degraded and undegraded tropical forest soils of north-eastern India as measured by ERIC–PCR fingerprints and 16s rDNA-DGGE profiles

Abstract

The analysis of the denaturated gradient gel electrophoresis (DGGE) of the polymerase chain reaction (PCR) amplified 16S rDNA fingerprints demonstrated a high diversity of bacterial communities in the soils from the three study sites at the surface and subsurface soil layers. The undegraded site possessed maximum number of 16S rDNA fingerprints than the degraded and undegraded sites at both soil depths. The surface soil of the degraded site displayed minimum 16S rDNA fingerprints thereby suggesting the reduced bacterial diversity in this site as a consequence of the long term utilization of the soil through shifting cultivation in the past. The cluster analysis of the DGGE bands of 16S rDNA genes revealed a clear separation of the degraded and moderately degraded sites from that of the undegraded site in terms of bacterial genomic communities.