Plant and Soil

, Volume 356, Issue 1, pp 265–277

The roots of the halophyte Salicornia brachiata are a source of new halotolerant diazotrophic bacteria with plant growth-promoting potential

Regular Article

DOI: 10.1007/s11104-011-0877-9

Cite this article as:
Jha, B., Gontia, I. & Hartmann, A. Plant Soil (2012) 356: 265. doi:10.1007/s11104-011-0877-9

Abstract

Soil salinity is the major cause limiting plant productivity worldwide. Nitrogen-fixing bacteria were enriched and characterised from roots of Salicornia brachiata, an extreme halophyte which has substantial economic value as a bioresource of diverse and valuable products. Nitrogen-free semisolid NFb medium with malate as carbon source and up to 4% NaCl were used for enrichment and isolation of diazotrophic bacteria. The isolates were tested for plant growth-promoting traits and 16S rRNA, nifH and acdS genes were analysed. For selected strains, plant growth-promoting activities were tested in axenically grown Salicornia seedlings at different NaCl concentrations (0–0.5M). New halotolerant diazotrophic bacteria were isolated from roots of S. brachiata. The isolates were identified as Brachybacterium saurashtrense sp. nov., Zhihengliuella sp., Brevibacterium casei, Haererehalobacter sp., Halomonas sp., Vibrio sp., Cronobacter sakazakii, Pseudomonas spp., Rhizobium radiobacter, and Mesorhizobium sp. Nitrogen fixation as well as plant growth-promoting traits such as indole acetic acid (IAA) production, phosphate solubilisation, and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity were demonstrated. For Brachybacterium saurashtrense and Pseudomonas sp., significant plant growth-promoting activities were observed in Salicornia in salt stress conditions. Salicornia brachiata is a useful source of new halotolerant diazotrophic bacteria with plant growth-promoting potential.

Keywords

1-aminocyclopropane-1-carboxylic acid (ACC) deaminase Acetylene reduction Halotolerant IAA production Plant growth-promoting rhizobacteria (PGPR) Salicornia 

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Discipline of Marine Biotechnology and EcologyCSIR-Central Salt and Marine Chemicals Research InstituteBhavnagarIndia
  2. 2.Department Microbe–Plant InteractionsHelmholtz Zentrum Muenchen, German Research Center of Environmental Health (GmbH)NeuherbergGermany