Arbuscular mycorrhizal fungus and rhizobacteria affect the physiology and performance ofSulla coronariaplants subjected to salt stress by mitigation of ionic imbalance

Abstract

AbstractSalt stress has become a major menace to plant growth and productivity. The main goal of this study was to investigate the effect of inoculation with the arbuscular mycorrhizal fungi (AMF;Rhizophagus intraradices) in combination or not with plant growth‐promoting rhizobacteria (PGPR;Pseudomonassp. (Ps) andBacillus subtilis) on the establishment and growth ofSulla coronariaplants under saline conditions. Pot experiments were conducted in a greenhouse andS. coronariaseedlings were stressed with NaCl (100 mM) for 4 weeks. Plant biomass, mineral nutrition of shoots and activities of rhizosphere soil enzymes were assessed. Salt stress significantly reduced plant growth while increasing sodium accumulation and electrolyte leakage from leaves. However, inoculation with AMF, whether alone or combined with the PGPRPseudomonassp. alleviated the salt‐induced reduction of dry weight. Inoculation with only AMF increased shoot nutrient concentrations resulting in higher K+: Na+, Ca2+: Na+, and Ca2+: Mg2+ratios compared to the non‐inoculated plants under saline conditions. The co‐inoculation with AMF andPseudomonassp. under saline conditions lowered shoot sodium accumulation, electrolyte leakage and malondialdehyde (MDA) levels compared to non‐inoculated plants and plants inoculated only with AMF. The findings strongly suggest that inoculation with AMF alone or co‐inoculation with AMF andPseudomonassp. can alleviate salt stress of plants likely through mitigation of NaCl‐induced ionic imbalance, thereby improving the nutrient profile.