| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2075453 | Biocatalysis and Agricultural Biotechnology | 2015 | 8 Pages |
Indole acetic acid is a phytohormone that plays a central role in plant growth and development. The present work was undertaken to shed some light on IAA metabolism in roots, nodules and non-rhizobial bacteria in nodule of Abrus precatorius L. Three IAA producing bacterial strains (A3CK, A7CK and A27CK) were isolated from the root nodule of legume A. precatorius L. and identified as Enterobacter spp. (Gammaproteobacteria) based on biochemical characteristics and 16S rDNA sequence homology. The root nodules of this plant contain higher amount of tryptophan, IAA and total phenol than the non-nodulated roots; but IAA metabolizing enzymes IAA oxidase, IAA peroxidase (E.C. 1.11.1.7) and polyphenol oxidase (E.C. 1.14.18.1) content were reversed. The Enterobacter spp. were found to produce copious amount of IAA in tryptophan supplemented YEM medium. The IAA production was enhanced with the optimization of the suitable carbon as mannitol, nitrogen as L-asparagine and vitamin as biotin sources in culture medium. The IAA production was also found to be stimulated by protocatechuic acid and ferulic acid in culture medium for A3CK and A7CK strain, respectively, but inhibited by rest of the phenolics tested. The presence of PGPR traits including ACC deaminase (E.C. 4.1.99.4) activity might be essential for plant microbe interaction, nodule function and plant growth promotion.
