Isolation and characterization of zinc solubilizing bacteria from Western Maharashtra soils

Abstract

The research was carried out at laboratory of plant pathology and Agricultural Microbiology, College of Agriculture, Pune. In the present investigation, efficient zinc solubilizing bacteria isolated from rhizospheric soils of Sangli and Satara districts of Western Maharashtra. Out of 45 samples, 9 bacterial isolates were obtained. Among the isolates, Pal-3 showed the highest efficiency, producing the largest zone of clearance (3.6 cm) on Bunt and Rovira medium. The zinc solubilization index among the isolates ranged from 2.59 to 3.57 while zinc solubilization efficiency varied between 129.41% and 257.14%. These values indicate significant variation in the zinc solubilizing capacity of the bacterial strains. Notably, Pal-3 exhibited both the highest solubilization index and efficiency, In addition to Pal-3, isolates Bor-1 and Pha-5 also showed strong zinc solubilizing ability. These three isolates were identified as the most efficient. Based on their cultural, morphological and biochemical characteristics, Pal-3 and Pha-5 were identified as Bacillus species whereas Bor-1 belonged to the Pseudomonas genus.