eng Enviro Research Publishers Current Agriculture Research Journal 2347-4688 2321-9971 2024-04-20 12 1 326 338 17778 article Vaishali Sanjay Randive 1 Snehal Nitin Agnihotri 2 Rani Babanrao Bhagat 3 Department of Biotechnology, Modern College of Arts, Science and Commerce College, Ganeshkhind, Pune-411016 Maharashtra India. Department of Microbiology, Tuljaram Chaturchand College, Baramati, Dist- Pune. Maharashtra, India Department of Botany, Baburaoji Gholap College of Arts, Commerce, and Science, Sangvi, Pune, Maharashtra, India. Indole Acetic Acid (IAA) production is important attribute of PGPR that promote plant growth and development. The rhizosphere is hotspot in the soil that harbors PGPR. The present study was aimed with isolation and screening of IAA producing bacteria from the rhizosphere of Pterocarpus marsupium Roxb. Optimum culture conditions (pH, temperature, incubation period and L-tryptophan concentration for IAA production were studied for selected isolates and their effect on wheat growth and root development  was  evaluated. Among twenty four IAA producing isolates five isolates (Et1, Rp1, Rp5, Rp6, and Rp9) produced maximum IAA in range of 50-70 μg/mL and was used in optimization studies. Maximum IAA was produced in 96 hours of incubation, at pH 7 and with 0.1mg/mL of L-tryptophan by all five isolates. 30^oC is the most suitable temperature for Et1, Rp1, Rp5, Rp9; whereas Rp6  produced   nearly same amount of  IAA at wide range of  temperature 30-35^oC (77-84.12 μg/mL) and  at pH 7-8 ( 73-74μg/mL). Out of the five isolates, Rp6 exhibits the highest potential, having a maximum IAA of 84.12 μg/mL at 35°C and pH 7.  Although tryptophan influences IAA synthesis but at higher concentration of tryptophan inhibits IAA synthesis. To validate the production of IAA, crude extracts were analyzed using thin layer chromatography (TLC). A spot of standard IAA with the same R_f value (0.91) was found to match a specific spot from the crude IAA. https://www.agriculturejournal.org/volume12number1/screening-and-optimization-of-iaa-production-by-pgpr-isolated-from-rhizosphere-of-a-pterocarpus-marsupium-roxb-and-their-effect-on-plant-growth/ IAA; PGPR; Pterocarpus marsupium; Rhizosphere; Tryptophan