Limited soil-soluble Phosphorus and inefficient application of chemical phosphate fertiliser cause a phosphorus (P) deficit, reducing crop yield. In this study, healthy soybean (Glycine max) plants from the Shirala region of Maharashtra, India, were used to isolate endophytic and rhizospheric bacteria. These bacteria were evaluated for phosphate-solubilising capacity and other PGP attributes. Ten bacterial isolates showed clear phosphate solubilisation halos on Katznelson’s and Bose agar medium, with the isolate SWK having the highest solubilisation index (3.50). Compared with the uninoculated control, a quantitative study in Pikovskaya’s liquid medium showed a 704.7% increase in soluble Phosphorus. The isolate SWK exhibited several important plant growth–promoting characteristics, including measurable nitrogenase activity (4.86 ± 0.32 µmol C2H4 per hour), positive ACC deaminase function, substantial formation of indole-3-acetic acid (28.7 ± 1.8 µg mL-1 with L-tryptophan supplied) and effective siderophore secretion, reflected by a D/d ratio of 2.18. Physiological and biochemical analyses further revealed that the isolate SWK is a Gram-negative, bacillus-shaped bacterium possessing considerable metabolic versatility, enabling it to adapt efficiently to diverse environmental conditions. The 16S rRNA method revealed that the isolate was Enterobacter hormaechei strain SWK (LC923381). The impact of bacterial inoculation on soybean growth was investigated in pot culture using different inoculation methods. An ANOVA showed substantial variation in plant height, stem thickness, root length, and total biomass among treatments (P < 0.001). The isolate SWK applied via combined rhizosphere irrigation and foliar spray produced the highest growth responses, including maximum plant height (46.8 ± 2.2 cm) and biomass (13.8 ± 0.7 g plant-1). Overall, Enterobacter hormaechei strain SWK showed superior plant growth–promoting efficiency, highlighting its potential as a biofertiliser for sustainable soybean cultivation.
Isolation, Rhizosphere, Morphological, Soybean
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