The rhizosphere is characterized by a large population of beneficial microorganisms. In this study, the ability of rhizobacteria to promote the growth of tomato plants in-vitro and in-vivo was investigated. Rhizosphere bacteria were isolated from soil and the root adhering samples of tomato plants and screened for growth promoting traits which include nitrogen fixation, phosphate and potassium solubilization and indole acetic acid (IAA) production. Eighteen rhizobacteria were isolated, 3 of the isolates (Nfb2, Psb2 and Ksb1) were considered as plant growth enhancers based on their in-vitro evaluation. All the three isolates were able to produce different amounts of IAA. Highest value was noticed in Ksb1 (60.0 ?g/ml) while the lowest was noticed in Psb2 (24.1 ?g/ml). All three isolates (Nfb2, Psb2 and Ksb1) showed in-vivo growth promotion in tomato plants. When compared to other PGPR combinations, treatment with PGPR isolate Psb showed maximum growth performance with mean values of shoot length, leaves and branches being 31.79 cm, 67.22 and 7.00 respectively while the mean values of the root length, wet weight and dry weight are 5.73 cm, 21.02 g and 4.29 g, respectively. All of the isolated strains showed significant enhancing effects on the growth of tomato plants as compared with the control. Therefore, the use of PGPR isolates is encouraged for better growth performance of plants.

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