چکیده (انگلیسی):

The effect of plant growth-promoting bacteria inoculation on plant growth and the sugarcontent in Agave americana was assessed. The bacterial strains ACO-34A, ACO-40, and ACO-140, isolated from the A. americana rhizosphere, were selected for this study to evaluatetheir phenotypic and genotypic characteristics. The three bacterial strains were evaluatedvia plant inoculation assays, and Azospirillum brasilense Cd served as a control strain. Phylo-genetic analysis based on the 16S rRNA gene showed that strains ACO-34A, ACO-40 andACO-140 were Rhizobium daejeonense, Acinetobacter calcoaceticus and Pseudomonas mosselii,respectively. All of the strains were able to synthesize indole-3-acetic acid (IAA), solubi-lize phosphate, and had nitrogenase activity. Inoculation using the plant growth-promotingbacteria strains had a significant effect (p < 0.05) on plant growth and the sugar content of A.americana, showing that these native plant growth-promoting bacteria are a practical, sim-ple, and efficient alternative to promote the growth of agave plants with proper biologicalcharacteristics for agroindustrial and biotechnological use and to increase the sugar contentin this agave species.© 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. This isan open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).