Volume : 2, Issue : 4, April - 2013

Characterization of Plant Growth Promoting Traits of Diazotrophic Bacteria and their Inoculating Effects on Growth and Yield of Rice Crops

Folguni Laskar , G. D. Sharma , B. Deb

Abstract :

The search for diverse plant growth promoting (PGP) nitrogen fixing bacteria is increasing day by day as efforts are increasing to exploit them as biofertilisers for various economically important crops. In the present study 12 diazotrophic strains belonging to 10 genera isolated from rice paddy fields were screened for multiple PGP traits and evaluated for their inoculation effects on rice plants. All the strains tested positive for ACC–deaminase activity and production of IAA. Additionally six strains are able to solubilise phosphorous. Based on these PGP activity the 6 strains were selected for inoculation study. Treatment with Sphingomonas azotifigens (JN085438) resulted in maximum plant growth and yield followed by Pseudomonas putida (JN222977) and Herbispirillum sp (JF990839). Our findings indicated that most of the selected strains possess multiple PGP properties that significantly improve the growth parameters of the plants when tested under controlled conditions.