Vegetal response of Acacia decurrens to inoculation with plant growth promoting rhizobacteria under salt stress

Abstract

Soil salinization is considered as an environmental limiting factor for plant growth and crops productivity in the world, mainly in arid and semiarid regions. An alternative for alleviating the caused stress by this abiotic factor is the use of Plant Growth Promoting Rhizobacteria (PGPR). These bacteria are able to improve plant growth through its various functions. The objective of this research was the isolation, characterization and effect determination of free living-halotolerant bacteria associated to Acacia decurrens. Microorganisms were biochemically characterized since ammonia production, cellulose production, exopolysaccharides production, total production of indoles and quantitative phosphorus solubilization determination and molecularly through 16S rRNA. Under greenhouse conditions, it was evaluated the effect of selected microorganisms under plant growth promotion in Acacia decurrens as of morphometric variables. Results demonstrated that the nine isolates under study exhibit in general a good metabolic activity, except isolates ACSA12 and ACSA19 which did not present cellulolytic production. Plant response showed evidence that isolates T4, T5 and T7 increased significantly biomass and plant development. These isolates were genetically identified as Pantoea deleyi ACSA12, Enterobacter amnigenus ACSA14 y Serratia liquefaciens ACSA19.

Keywords

• enterobacter amnigenus
• salinity
• serratia liquefaciens
• pantoea deleyi