Characterization of phosphate-solubilizing bacteria isolated from the arid soils of a semi-desert region of north-east Mexico

Abstract

Phosphorus is an essential element for plant growth. But more than 90% of applied phosphorus is not available to plants since it forms an insoluble complex with aluminium or iron in acid soils and with calcium in alkaline soils. This is a major problem in arid and semiarid regions where availability is affected principally by the insoluble complex formation with calcium. It is well known that phosphate-solubilizing bacteria facilitate the availability of phosphorus in such soils and thereby contribute to soil fertility. There has been no report of such bacteria in the arid soils of the semi-desert region in the State of Coahuila, north-east Mexico. In this study, 20 phosphate-solubilizing bacterial strains were isolated and screened for their phosphate-solubilizing capacity. Four out of these 20 strains were selected, based on their ability to solubilize phosphate (around 70%), for molecular characterization and they were identified as Pseudomonas sp. and Enterobacter sp.