Characterization and Plant Growth-Promoting Potential of Enterobacter Cloacae B3 Isolated from the Rhizosphere of Cajanus Cajan

Abstract

The present study characterized bacterial isolate B3 obtained from the rhizosphere of Cajanuscajan and evaluated its plant growth-promoting potential. Morphological, physiological, biochemical, and molecular analyses identified the isolate as Enterobactercloacae B3. The isolate was a motile, rod-shaped, non-spore-forming bacterium capable of tolerating alkaline pH, moderate salinity, and elevated temperatures, indicating strong environmental adaptability. Biochemical studies showed metabolic versatility, while 16S rRNA gene sequencing confirmed its close relationship with other Enterobactercloacae strains. The isolate exhibited multiple PGPR traits including phosphate, potassium, zinc, and magnesium solubilization, sulfur oxidation, siderophore production, and IAA production. It also produced important hydrolytic enzymes such as chitinase, cellulase, amylase, lipase, and protease. These multifunctional properties suggest that Enterobacter cloacae B3 has strong potential as a biofertilizer and biocontrol agent for sustainable agriculture and soil fertility improvement.