Multipotent Plant Probiotic Rhizobacteria from Western Ghats and Its Effect on Quantitative Enhancement of Medicinal Natural Product Biosynthesis

Understanding the chemical basis of rhizobacterial-plant interaction provides immense opportunities for the enhancement of agricultural productivity. In the current study, use of eighteen different rhizosphere samples from Western Ghats has resulted in the isolation of 92 rhizobacteria. All the isolates were screened for plant probiotic potential and found to have varying distribution of plant growth promoting characteristics. IAA production was quantitatively analysed by high performance liquid chromatography (HPLC) and high performance thin layer chromatography (HPTLC) for eight selected isolates with multiple plant beneficial traits. This has resulted in the identification of maximum IAA production (1724.23 µg/mL) by Providencia stuartii . In vivo confirmation of plant growth enhancement effect of selected isolates was carried out using the seedlings of Vigna radiata and Phaseolus vulgaris . The isolates were further analysed for their effect on quantitative enhancement of saponin contents in the medicinal plant Bacopa monnieri . Statistical analysis of the results of the study showed excellent growth promoting and secondary metabolite enhancement effects of selected organisms. The study highlights immense applications of selected isolates in organic farming practices.