Prospects of zinc solubilizing bacteria for enhancing growth of maize

Zinc (zn) is an important micronutrient and its adequate supply is considered indispensable for growth,development and normal functioning of plants. recent reports reveal that more than 70% of pakistani soils are zn deficient. znso4,containing 33% zn,is commonly used,but only 4-8% of the total applied zn is available to plants while remaining gets fixed into soil. contrarily,zinc oxide is a cheaper and insoluble source which contains 80% zn. however,zinc solubilizing bacteria could be used to solubilize insoluble sources of zinc (zno). keeping in view the above stated problem,the present study was conducted for isolation,screening,identification and characterization of efficient zinc solubilizing bacteria for improving growth of maize. several bacteria were isolated from rhizosphere of maize through dilution plate technique. the selected bacterial isolates,capable of solubilizing zno,were further screened for their plant growth promoting activity under axenic conditions. out of ten bacterial isolates,az6 was found best strain on the basis of maximum zinc solubilization potential and growth promotion of maize. the selected bacterium was identified as bacillus sp. az6 (accession # kt221633). bacillus sp. az6 had different growth promoting attributes and also ability to produce organic acids. © 2015,university of agriculture. all rights reserved.