Optimization of medium for indole-3-acetic acid production using Pantoea agglomerans strain PVM

Aims: To optimize the medium components for the production of indole‐3‐acetic acid (IAA) by isolated bacterium Pantoea agglomerans strain PVM. Methods and Results: Present study deals with the production of an essential plant hormone IAA by a bacterial isolate P. agglomerans strain PVM identified by 16S rRNA gene sequence analysis. The medium containing 8 g l^?1 of meat extract and 1 g l^?1 of l ‐tryptophan (precursor) at optimum pH 7, 30°C and 48‐h incubation gave the maximum production of IAA (2·191 g l^?1). Effect of IAA synthesized on in vitro root induction in Nicotiana tobacum (leaf) explants was compared with that of control. IAA was characterized by high‐performance thin‐layer chromatography, high‐performance liquid chromatography and gas chromatography–mass spectroscopy. Conclusions: Pantoea agglomerans strain PVM was a good candidate for the inexpensive and utmost production of IAA in short period, as it requires simple medium (meat extract and l ‐tryptophan). Significance and Impact of the Study: The present report first time showed the rapid, cost‐effective and maximum production of IAA. No reports are available on the optimization of particular medium components for the production of IAA. This study demonstrates a novel approach for in vitro root induction in N. tobacum (leaf) explants.