Sarcouncil Journal of Applied Sciences Aims & Scope

Abstract: This work compares and synergistically tests the plant growth promoting rhizobacterium bacteria (Bacillus cereus) and arbuscular mycorrhiza fungus (Rhizophagus irregularis) in diminishing of the severe salinity stress (200 mM NaCl) in wheat (Triticum aestivum L.) under controlled conditions. Four treatments were tested - control, PGPR, AMF and a combined consortium with 5 replicates each. Growth attributes (length of shoots and roots, dry biomass, leaf area) and important physiological and biochemical indicators (chlorophyll content, proline accumulation, relative water content, and superoxide dismutase activity) were measured. Salinity stress resulted in a large decrease (40-50%) in the experimental parameters used in the study for the untreated control caused by osmotic imbalanced and the toxic to Na+. Inoculation with B. cereus increased plant performance by 23-45%, which was explained by an increased synthesis of phytohormones (IAA) and the formation of exopolysaccharides. R. irregularis inoculation resulted in more substantial improvements (30-64%) by developing extraradical hyphal networks that enhanced the uptake of N, P, and K. The combination of PGPR and AMF showed the strongest effect with the improvements ranging from 47-86% i.e. 69% increase in dry biomass, 86% increase in SOD activity, 40% decrease in Na+ accumulation and 40% increase in proline levels. These results point to the great synergistic possibility of PGPR--AMF co-inoculation as an eco-efficient approach to improve tolerance of wheat under high salinity stress.