Metabolic and Genetic Diversities of Rhizobacteria Isolated from Degraded Soil of Ethiopia

Abstract

Genetic and metabolic diversities are sources of biodiversity that provides adaptation and could help to cope with environmental stresses. Thus, the study was initiated to assess the metabolic and genetic diversities of rhizobacteria from degraded soil through BOX-PCR and 16S rRNA sequencing. A total of eighty isolates were subjected to carbohydrate and amino acid utilization tests, BOX PCR and 16S rRNA profiling. The phenotypic profiling comprised utilization of C and N sources revealed metabolic versatility of the strains (14.29 to 100%). Accordingly, Ochrobactrum, Pseudomonas and Klebsiella spp expressed notable metabolic versatilities. BOX-PCR showed greater diversity with high degree of polymorphism. Simpson’s Index of Diversity (0.883) took the leading position with Bacillus species. The 16S rRNA showed that the isolates assigned to phyla Firmicutes (21.92%) and Proteobacteria (78.08%). The most dominant species were Pseudomonas (23%) and Ochrobactrum (21%). Metabolic and genetic diversities of the rhizobacteria reveal their potential for plant growth improvement under water deficient soil.