Genetic and functional diversity of fluorescent Pseudomonas from rhizospheric soils of wheat crop

Abstract

Wheat rhizospheric soils were collected from different part of northern and eastern Indo-Gangetic plains, which is being irrigated from water of Ganga River. Isolation of fluorescent Pseudomonas species was carried out from the soil samples collected. The percentage of isolates positive for indolic compound, P-solubilisation, siderophore production and ACC deaminase activity were 64.0, 38.6, 63.5, and 19.7, respectively. A total of 543 isolates were randomly selected for studies based on the genus specific confirmation by the Pseudomonas specific primer. Among the 543 isolates, 26 different clusters were formed from 16S rDNA-RFLP whereas 27 clusters were generated by the rpoB-RFLP with similarity percent ranging from 3 to 100%. 16S rDNA sequencing showed 9 different species of Pseudomonas whereas, rpoB sequencing showed 13 different species of Pseudomonas. Phylogenetic analysis based on 16S rDNA gene sequences generated 15 branches showing the more than 70% of boot strap value, whereas 18 branches in the rpoB based phylogenetic tree were supported by bootstrap values above 70%. Diversity indices based on rpoB were higher than the ribosomal RNA gene.