Metabolic potential of microorganisms associated with the halophyte Aster tripolium L. in saline soils

Abstract

Increased soil salinization may be caused by a natural (e.g. climate change) and anthropogenic (e.g. improper fertilization and irrigation of agricultural land) factors. The submitted work assumes that microorganisms associated with plant halophytes have a unique metabolic properties that can stimulate plant growth under salt stress. The aim of the study was to determine the abundance and metabolic biodiversity of endophytic and rhizosphere microorganisms co-existing with Aster tripolium L. and compare them with the properties of soil microorganisms not affected by plant roots at a salty meadows in the vicinity of a soda factory (central Poland). In order to select halotolerant and halophilic microorganisms culture medium was enriched with various concentrations of NaCl (0, 100, 200, 400, 600 mM NaCl). Total metabolic activity of endophytic, rhizosphere and soil populations was measured to compare the community-level physiological profiles. Results of our study revealed that bacterial and fungal density increased in the following order: endophytes < soil