Structural and functional insights of microbial community with respect to salinity levels in a reclaimed land at South Korea
Exploring the microbial response to soil salinity is of great importance for better understanding of microbial adaptation and evolution in reclaimed land for proper land utilization. However, the knowledge on microbial response and adaptation in salt affected reclamation land is very less. The present study was aimed to demonstrate the microbial community structure and the functional gene changes with respect to different levels of soil salinity. Soil samples were collected from salt affected Saemangeum reclaimed land, South Korea and grouped into non saline (NS) and highly saline (HS) soils based on soil salinity level. Soil DNA was extracted and high throughput sequence analysis was performed for bacteria and fungi by targeting V1-V3 and ITS region respectively by using 454 GS FLX Titanium sequencing system. The sequences were processed using Mothur pipeline. Totally 1957 and 2495 sequences were obtained from bacteria and fungi respectively. Higher relative abundance of Proteobacteria, Actinobacteria and Verrucomicrobia were found in HS soil compared to NS soil. Similarly the abundance of fungal phylum Ascomycota and Chytridiomycota were found to be higher in HS soil. Correlation analysis indicated that soil EC (P< 0.001) and Na+ (P< 0.01) significantly affected the diversity of bacteria and fungi. Higher abundance of bacterial stress related protein and enzymes in HS soil were observed. This study helped us to identify the dominant microflora of the salt affected reclaimed land and higher abundance of proteins responsible for salinity tolerance in HS soil indicated the possible adaptation mechanisms of the microorganisms.