Rhizobacteria containing ACC-deaminase confer salt tolerance in maize grown on salt-affected fields

• Published in: Canadian journal of microbiology Vol. 55; no. 11; p. 1302
• Main Authors: Nadeem, Sajid Mahmood, Zahir, Zahir Ahmad, Naveed, Muhammad, Arshad, Muhammad
• Format: Journal Article
• Language: English
• Published: Canada 01-11-2009
• Subjects: Agriculture; Alphaproteobacteria - enzymology; Alphaproteobacteria - physiology; Carbon-Carbon Lyases - metabolism; Pakistan; Salt-Tolerance; Soil Microbiology; Symbiosis; Zea mays - growth & development; Zea mays - microbiology; Zea mays - physiology; Pakistan
• ISSN: 1480-3275
• DOI: 10.1139/W09-092

Salt stress is one of the major constraints hampering agricultural production owing to its impact on ethylene production and nutritional imbalance. A check on the accelerated ethylene production in plants could be helpful in minimizing the negative effect of salt stress on plant growth and development. Four Pseudomonas, 1 Flavobacterium, and 1 Enterobacter strain of plant growth promoting rhizobacteria containing 1-aminocyclopropane-1-carboxylate (ACC)-deaminase were selected and their effects on growth and yield of maize were investigated to improve the salt tolerance of maize grown on salt-affected fields. The selected rhizobacterial isolates reduced or eliminated the classical "triple" response, indicating their ability to reduce stress-induced ethylene levels. Results showed that rhizobacterial strains, particularly Pseudomonas and Enterobacter spp., significantly promoted the growth and yield of maize compared with the non-inoculated control. Pseudomonas fluorescens increased plant height, biomass, cob yield, grain yield, 1000 grain mass, and straw yield of maize up to 29%, 127%, 67%, 60%, 17%, and 166%, respectively, over the control. Under stress conditions, more N, P, and K uptake and high K+-Na+ ratios were recorded in inoculated plants compared with the control. The results imply that inoculation with plant growth promoting rhizobacteria containing ACC-deaminase could be a useful approach for improving growth and yield of maize under salt-stressed conditions.