Species Composition and Diversity Dynamics of Actinomycetes in Arid and Semi-arid Salt Basins of Rajasthan.

Species composition and diversity dynamics of the actinomycetes was studied in five salt basins of arid and semi-arid areas of Rajasthan, India. A novel approach integrating molecular (16S rRNA gene) and diversity indices was applied to reveal species composition and diversity dynamics. Fifty-three actinomycetes isolates were isolated from five arid and semi-arid salt basins. Molecular characterization resulted in the identification of actinomycetes species belonging to three genera namely, Streptomyces, Nocardiopsis, and Actinoalloteichus. The diversity study among actinomycetes species validates their universal occurrence in arid and semi-arid regions of Rajasthan. The species N. dassonvillei subsp. albirubida was omnipresent in all the five salt basins but its relative manifestation was not static across habitats. The study revealed that three species N. chromatogenes, S. durbertensis, and S. mangrovicola are being reported for the first time from India. The maximum species of actinomycetes were recorded from Pachpadra (14) and the minimum from Didwana area (6). This study not only documents the hitherto wealth of actinomycetes species in arid and semi-arid salt basins of Rajasthan but also reveals the composition and diversity dynamics of actinomycetes.