Isolation and characterization of Medicago sativa L. symbiotic bacteria in phosphorus solubilizing capacity and tolerance to saline stress

Abstract

With the objective of isolating strains of rhizobia, symbionts of Medicago sativa L. (alfalfa), and
characterizing their ability to promote plant growth, the research and selection of microorganisms
were carried out in soils of different productive areas of the country. The collection was
evaluated in the ability to solubilize phosphorus and resistance to saline environments. In the
collection of 58 isolates, 5 show the ability to solubilize phosphorus. It was determined that the
highest percentage of isolates tolerant to salinity (3.5% ClNa) were from Magdalena (26%).
From the selected isolates, the percentage of nodulated plants (PPN) was determined, according
to the methodology used by SENASA - Res. 264/2011. Most of the isolates evaluated
induced nodule formation in a percentage of plants greater than 80%. The characterization of
these strains is likely to allow us to identify individuals with a biotechnological potential for their
use as bioinoculants.