DEVANGEE P. SHUKLA, AMITA Y. MISHRA AND NAYAN K. JAIN
Abstract
Plant growth promoting bacteria (PGPB) play an important role to increase in soil fertility, plant growth promotion, and suppression of phytopathogens for development of ecofriendly sustainable agriculture. The use of PGPB has been proven to be an environmentally sound way of increasing crop yields by facilitating plant growth through either a direct or indirect mechanism. Herein study, 40 PGP bacterial strains isolated from samples collected from electroplating industrial wastewater of GIDC Electronic estate, Sector-25, Gandhinagar [23.2464° N, 72.6314° E] of Gujarat state (India). Wastewater samples (Sample1- Sample 5) were analyzed for physico-chemical parameters. All isolates were divided in to five groups and studied for their nutrient solubilization, PGP viz. indole acetic acid (IAA), ammonia (NH3) and hydrogen cyanide (HCN), hydrolytic enzymes and secondary metabolite production traits in vitro. The isolates were also screened in different parameters of environmental condition viz. Nacl, and temperature. The PGPB were found and most probably belong to five genera based on their morphological and biochemical traits namely Pseudomonas (11), Serratia (12), Bacillus (4), Arthrobacter (6) and Micrococcus (7). The isolates of group 1-4 were motile, rods and non-spore formers whereas group-5 isolates were non-motile, coccus and non-spore formers. Out of the 40 isolates, 23 were Gram-negative while 17 were Gram-positive. Besides, 17 were positive for IAA production, 28 for NH3 production, 23 for citrate utilization, 12 for VP, all were negative for methyl red test, 10 for starch hydrolysis, 11 for succinic acid production, 27 for HCN production and 18 for oxidase.