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

ABSTRACT

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 40 mg kg⁻¹) combined with two levels of salinity (control and 10 dS m⁻¹) using Ni(ii) nitrate hexahydrate (Ni(NO₃)₂.6H₂O) 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 20 mg kg⁻¹, and negatively at 40 mg kg⁻¹ concentration both in control and at 10 dS m⁻¹. Ni (20 mg kg⁻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 20 mg kg⁻¹ increased wheat growth by alleviating salinity stress; however, at 40 mg kg⁻¹ it aggravated the plant stress and decreased the plant growth.

Keywords:

• Ni
• plant physiology
• salinity
• wheat