Salinity has adversely affected the soil properties and plant productivity. Phaseolus vulgaris (Pole bean) is one of the important crops for human consumption that is considered very sensitive to salinity stress. However, nanoparticle application under severe stress conditions has mitigated salinity impact. In this experiment, the effect of spraying of iron oxide nanoparticles at (0, 10, 20 and 30 µM Fe2O3) has been examined on the Pole bean seed germination, soil properties and Pole bean growth parameters under 200 mM NaCl. Salinity at 200 mM reduced significantly the seed germination, shoot length, root length, root volume, shoot fresh and dry weight, root fresh and dry weight, leaf number, leaf area, leaf relative water content, chlorophyll a and b, carotenoids, total and soluble carbohydrate in the shoot and root, total and soluble proteins in the shoot and root, the free amino acid in the shoot and minerals content (N, Fe, P and k) in the shoot and root, whereas, salinity increased the Na content in the shoot and root compared to control. On the other hand, the foliar method of Fe2O3 at different doses under salinity increased all plant growth and enhanced the metabolism functions. The foliar application of 10 µM Fe2O3 + 200 mM NaCl improved the seed germination percentage, shoot length, root length, root volume, shoot fresh weight, leaves number, soluble carbohydrate in the shoot and root, soluble proteins in the shoot and root, P the shoot and root and K in the root, but Na reduced in the shoot. Furthermore, spraying the 20 µM Fe2O3 + 200 mM NaCl increased the leaf area, root fresh weight, relative water content, chlorophyll b, carotenoids, total carbohydrate in the shoot, and total proteins in the shoot and root, the free amino acid in the shoot and K in the shoot. In addition, foliar application at 30 µM Fe2O3 + 200 mM NaCl raised the chlorophyll a, total carbohydrate in the root, N in the shoot and root, while the Na declined in the root. Both concentrations of Fe2O3 NPs at 20 and 30 µM under 200 mM NaCl enhanced the Fe in the shoot and root.
