Journal of Pure and Applied MicrobiologyVol. 9 No. 3

Potential of Rhizobium Strains Isolated from Agave americana L. as Plant Growth Promoting Rhizobacteria

Luis Galdino Garcia-Perez1, Clara Ivette Rincon-Molina2, Victor Manuel Ruiz-Valdiviezo2, Federico Antonio Gutierrez-Miceli2, Nestor Hugo Cruz-Perez2, Juan Jose Villalobos Maldonado2 and Reiner Rincon-Rosales2*

1Centro de Ciencias Genomicas, Universidad Nacional Autónoma de Mexico, Cuernavaca, Morelos, Mexico. 2Laboratorio de Biologia Molecular. Instituto Tecnologico de Tuxtla Gutierrez, Carretera Panamericana km. 1080, C.P. 29050, Tuxtla Gutierrez, Mexico.

Received on 05 May 2015 and accepted on 06 July 2015

 

ABSTRACT

The use of indigenous Plant Growth-Promoting Rhizobacteria (PGPR) as a biofertilizer is an appealing alternative to enhance the growth and increase the yield of crops grown in nutrient-limited soils. The objective of this study was to determine the efficiency of four rhizobia strains isolated from the rhizosphere of Agave americana L. as PGPR. The characteristics of the isolated strains ACO-R05, ACO-R19, ACO-R35, and ACO-R62 were determined using several morphological, physiological, and biochemical tests. The taxonomic status of the strains was done by means of a phylogenetic study based on 16S rDNA chromosomal genes. The efficiency of rhizobia strains to solubilize P, auxins (IAA), and gibberellins (GA), as well as to biosynthesize and fix N2 was determined. The PGPR potential of the strains was determined through inoculation tests using Agave americana as a plant trap. According to the phenotypic characteristics and the phylogenetics based on 16S rDNA sequences, these strains were grouped within the genus Rhizobium. All evaluated Rhizobium strains were able to solubilize phosphate, synthesize indole-3-acetic acid (IAA) and gibberellins (GA). The inoculation using the rhizobacterias strains had a significant effect (P<0.05) on the growth of A. americana. Biofertilization using native PGPR-Rhizobium proved to be a practical, simple, and efficient alternative to promote growth in this agave species.

Keywords : Agave, Biofertilization, PGPR, Rhizobium.