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Salinity stress (NaCl) and heavy metals contamination (CdCl2) are the serious environmental constraints for decreased crop production worldwide. However, the interaction between NaCl and CdCl2 regarding sodium (Na), cadmium (Cd), and chloride (Cl) accumulation in plants has not been completely established. Therefore, the interactive effects of NaCl andCdCl2 on plant growth, Na, Cd, and Cl accumulation in plants, and wheat yield were evaluated. Wheat seeds were cultivated in clay loam soil under greenhouse conditions. After two weeks of sowing, plants were subjected to NaCl at the rate of 0, 50, and 100 mM either alone or in combination with CdCl2: 0, 1, and 2 mM, respectively. The results revealed that increasing NaCl and CdCl2 levels reduced Na and Cd concentrations, whereas enhanced Cl concentrations. Furthermore, moderate levels of CdCl2 and NaCl stresses enhanced the antioxidative enzymatic activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in addition to proline accumulation in wheat leaves. By contrast, 100 mM NaCl in combination with 2 mM CdCl2 enhanced H2O2 accumulation by 105%, which thus decreased the membrane stability index (MSI) by 49% and wheat yield by 27% as compared to 2 mM CdCl2. The reduced Cd toxicity by NaCl or Na accumulation in plant tissues by CdCl2 involved competition between Na and Cd at binding sites, however, enhanced Cl phytotoxicity in plants resulted in the overproduction of H2O2 that was not quenched by antioxidative enzymes, thereby decreased MSI and wheat yield.

来源平台：JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION