Soil community analysis along a salt gradient using denaturing gradient gel electrophoresis of PCR-amplified 16s rRNA genes
Many studies of hyper saline environments have been performed, mainly on aquatic systems. However, the microbial community in terrestrial thallasohaline environments has not been studied extensively. To our knowledge, this is the first study of a natural terrestrial thallasohaline environment using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). We studied the great salt plains (GSP) for this purpose. The GSP is a perfect example of an extreme environment. The environment of the GSP changes frequently due to rain events that can change the salinity of the soil. Salt gradient samples and core samples were collected from the GSP in different years and DNA extractions were performed. 16S rRNA genes were amplified using PCR and examined on DGGE gels. Banding patterns of the DGGE gels were analyzed using Quantity One-Versa Doc software. Based on the banding patterns after DGGE, it was shown that the low- and high-salt soil samples had greater band richness than medium-salt soil samples. A dendrogram of relatedness was made and the samples were placed in different phenons using NTSYS. Core samples collected from the same locations exhibited similar microbial communities, and samples collected in different years from same location exhibited different microbial communities. Environmental factors such as soil salinity, water flow, and temperature, vary from year to year and from place to place on the GSP, which can select for different microbial communities in soil samples collected from the same place in different years and soil samples collected from different places on the GSP.
Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences.