Evaluation and Comparison of the Toxic Effects of MgO NPs, ZnO NPs, α-Fe 2 O 3 NPs, γ-Fe 2 O 3 NPs, and Fe 3 O 4 NPs on the Remediation for Cadmium-Related Effects in Wheat Seedlings

In order to find the best nanometal oxides to alleviate the cadmium-caused toxicity, we chose five kinds of nanometal oxides (MgO NPs, ZnO NPs, α-Fe 2 O 3 NPs, γ-Fe 2 O 3 NPs, and Fe 3 O 4 NPs) tried to research the different effects. In this study, the effects of nanometal oxides on physiological response indicators in wheat seedlings poisoned by cadmium were figured out. The results showed that the properties of nanometal oxides were related to their capacity to mitigate the toxicity induced by cadmium. Comparatively, 30 mg/L MgO NPs showed the best repair effect, as well as it can also alleviate the significant abiotic stress caused by Cd 2+ on plants. The activity of antioxidant enzymes had been reduced and the growth of plants had been improved after the addition of MgO NPs. ZnO NPs showed further toxicity to Cd-poisoned wheat seedlings. Among the three nanoiron oxides, Fe 3 O 4 NPs has a relatively good repair effect, which may be related to its Fe(II)—an essential element required for plant growth.