Plant Growth Promoting Rhizobacteria (PGPR) with multiple beneficial traits, serve as potentially, ecofriendly and cost effective alternatives to chemical fertilizers and pesticides. They have both direct and indirect affirmative impacts on overall plant growth and health. PGPR are well-known to directly improve plant growth by phytohormone production and availability of minerals in soil. Total nine soil samples were taken from near the rhizospheric zone of different crops and 56 rhizobacterial strains were isolated. Out of 56 rhizobacterial strains, 16 strains were found positive for more than one beneficial trait that included solubilization of phosphate, indole acetic acid (IAA), siderophore, ammonia and H2S production. Among of these 16, 4, 5, 10 and 6 PGPR strains were found positive for only one function, either phosphate solubilization, siderophore, IAA, ammonia and H2S production, respectively. Among all PGPR strain, RKM15 was observed having the highest phosphate solubilizing index, solubilized phosphate (3.4 and 339 mg L-1) and also siderophore unit (70.54 %). The maximum IAA production was observed by RKM25 strain (35.56 µg mL-1). The most promising RKM15 isolate was identified as Pantoea dispersa (MN629239) through 16S rRNA gene sequencing technique. This characterized PGPR strain may be used for development of biofertilizers, to enhance crop productivity and improvement in soil fertility.
Key words: Rhizobacteria, Phytohormone, Phosphates solubilization, Siderophores, IAA
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