COMPARISON OF THE EFFECTS OF ZNO NPS, MGO NPS AND IONIC ZINC AND MAGNESIUM ON WHEAT PLANTS

Due to special properties, ZnO and MgO nanoparticles (NPs) have wide applications in various fields and can be easily dispersed into air and soil. Plants contacts soil directly and are also an important source of food. Hence, studies on phototoxicity of ZnO NPs and MgO NPs to plants are needed. In this study, wheat plants were exposed to ZnO NPs, MgO NPs and ionic Zn, Mg at concentration of 50 and 200 mg/L dissolved in water. Growth parameters, Zn and Mg accumulation, total protein, soluble sugar and antioxidant system were determined after 4 days of treatment. Results showed that ionic Zn and Mg reduced the shoot and root length and also lead to increments of total proteins, soluble sugars and antioxidant enzyme activity. 200 mg/L Mg2+ increased chlorophyll contents by 29%. 200 mg/L Mg2+ and ZnO NPs also increased root activity. In other words, Zn and Mg oxide nanoparticles exhibited less physiology toxicity than ionic Zn and Mg of the same concentration.