Journal of Food, Agriculture and Environment

Molecular and physiological characterization of plant growth promoting rhizobacteria from rhizosphere soil in Al-Qassim, Saudi Arabia


Abdullah S. Alsohim

Recieved Date: 2015-01-18, Accepted Date: 2015-03-29


Plant growth-promoting bacteria (PGPB) are associated with many plant species. The most widely studied group of PGPB are plant growth-promoting rhizobacteria (PGPR) colonizing the root surfaces. PGPR have shown promise as biofertilizers. Moreover, phosphorus solubilizing bacteria (PSB) are important for crop plants as they increase phosphorus uptake. The goal of this study was the identification of PGPR isolates by 16S rDNA sequencing, and the evaluation of their ability of phosphorus solubilizing and their physiological traits. Eighteen soil samples were collected from the rhizosphere of alfalfa plants in different areas of Al-Qassim region. The isolates were identified using 16S rDNA gene sequencing. Based on 16S rDNA gene sequencing, these bacterial strains were identified under several genera: Enterobacter, Acinetobacter, Pantoea, Stenotrophomonas, Klebsiella and Serratia. In a total of eighteen isolates from alfalfa, just 4 isolates (Acinetobacter calcoaceticus, Acinetobacter baumannii, Klebsiella pneumoniae and Serratia marcescens) showed high ability in phosphorus solubilizing. All the PGPR isolates were able to grow in NaCl up to 6% and temperatures between 35 and 40°C. QUSA 6, identified as Acinetobacter lwoffii, was found to grow even at 50°C. Therefore, these isolates may have a potential to act as plant-growth-promoting rhizobacteria and can enhance plant growth, particularly under stressed environmental conditions.


PGPR, 16S-rDNA, phosphorus solubilizing, salinity, heat stress

Journal: Journal of Food, Agriculture and Environment
Year: 2015
Volume: 13
Issue: 2
Category: Agriculture
Pages: 118-121

Full text for Subscribers

Note to users

The requested document is freely available only to subscribers/registered users with an online subscription to the Journal of Food, Agriculture & Environment. If you have set up a personal subscription to this title please enter your user name and password. All abstracts are available for free.

Article purchasing

If you like to purchase this specific document such as article, review or this journal issue, contact us. Specify the title of the article or review, issue, number, volume and date of the publication. Software and compilation, Science & Technology, all rights reserved. Your use of this website details or service is governed by terms of use. Authors are invited to check from time to time news or information.

Purchase this Article:   20 Purchase PDF Order Reprints for 15

Share this article :