Effect of Enhanced Nickel Levels on Wheat Plant Growth and Physiology under Salt Stress

A pot experiment was conducted to study the response of wheat to concurrent stresses of salinity and nickel (Ni)-toxicity. Soil was spiked with Ni (0, 20 and 40mgkg(-1)) combined with two levels of salinity (control and 10 dS m(-1)) using Ni(ii) nitrate hexahydrate (Ni(NO3)(2).6H(2)O) and sodium chloride (NaCl), respectively, in a completely randomized design with four replicates. Plants were harvested at the tailoring stage and the results showed that wheat growth was positively affected by Ni at 20mgkg(-1), and negatively at 40mgkg(-1) concentration both in control and at 10 dS m(-1). Ni (20mgkg(-1)) had a nonsignificant positive effect on tissue potassium (K+) and a significant negative effect on Na+ concentration. Moreover, Ni translocation from root to shoot and accumulation decreased by increasing the levels of Ni in both control and salinity treatments. It can be concluded that Ni at 20mgkg(-1) increased wheat growth by alleviating salinity stress; however, at 40mgkg(-1) it aggravated the plant stress and decreased the plant growth.