Evaluation of symbiosis efficiency of arbuscular mycorrhiza (Rhizophagus intraradices) and root endophyte Piriformospora indica under salinity stress in Glycirrhiza glabra L.

Symbiotic fungies such as mycorrhiza can alleviate biotic and abiotic stresses in host plants and affect their growth, nutrition and tolerance to salinity stress. Glycyrrhiza glabra is commonly grown in Asia for medicinal purpose and fodder source for livestock. In order to assess the effect of entophytic fungi symbiosis on growth and some physiological properties of G. glabra under different levels of salinity, an experiment was conducted in a factorial design with combination of two factors, salinity levels (non-saline, 4, 8, 12 and 16 dS m-1) and symbiotic fungi (non-inoculated, inoculated with Piriformospora indica orRhizophagus intraradices) in three replicates. Results showed the decrease of root fungal colonization, shoot and root dry weight and root length, and shoot K and P content with increasing of salinity levels. Phosphorus and K utilization efficiency were decreased by increasing of salinity levels. Moreover, salinity caused a significant increase in electrolyte leakage and Na+/K+ ratio. R. intraradices colonization considerably increased tolerance index under salinity stress and decreased Na+/K+ ratio. R. intraradices inoculated plants showed greater biomass, P and K content in comparison with non-inoculated and P. indica inoculated plants. While plant inoculating with P. indica resulted in an increase in shoot dry weight at non-saline condition, and did not significantly affect other studied parameters. Results of this study indicated the ameliorating effects of arbuscular mycorrhizal symbiosis in G.glabra under salinity stress, and the utilization ability of this symbiosis in phytoremediation of salt affected soils.