Isolation and Characterization of Indole Acetic Acid Producing Bacteria from Rhizosphere Soil and their Effect on Seed Germination

Indole acetic acid (IAA) is one of the most important phytohormones enhances the root structure and plant growth. The present study provides the isolation and characterization of IAA producing bacteria from rhizosphere soil and their effect on seed germination. Out of 30 isolates, eight (viz. Aux 4, Aux 9, Aux14, Aux16, Aux 19, Aux 20, Aux 21 and Aux 25) were able to produce IAA which was confirmed by Salkowski reagent test. Isolates were characterized on the basis of visual observations, gram staining and biochemical tests such as oxidase, catalase, indole, TSI, methyl red, Voges-Proskauer, citrate utilization, urease and starch hydrolysis test. The IAA producing bacteria are rod and round shaped gram positive and gram negative bacteria. In biochemical tests,…