Effects of Iron Supply on Cadmium and Zinc Uptake and Translocation by Cucumber Seedlings
Plant nutrition may influence the uptake of heavy metals by plants. In this study, the effects of different iron(Fe)supply on the uptake and translocation of cadmium(Cd)and zinc(Zn)by cucumber seedlings were studied in nutrient solution. Cadmium concentrations in different parts(root, stem and leaf)of cucumber seedlings were significantly higher under iron deficiency than iron sufficiency, especially in stems. The concentrations of Cd in stems under Fe deficiency were 2.9, 2.8 and 2.4 times those of 50, 100 and 200μmol·L-1 iron supply, respectively. Meanwhile, Fe-deficient treatment also increased the Zn concentrations in roots and leaves, but did not influence the Zn con-centrations in stems. The uptake of Cd and Zn by roots showed significantly negative correlation with Fe uptake. The percentages of Cd allo-cated in roots increased with increasing Fe levels in nutrition solution. Compared with the Fe-deficient treatment, 200μmol·L-1 Fe treat-ment increased the distribution of Cd in root by 43%, but decreased that in stems and leaves by 59%and 44%, respectively. However, Fe treatments had no significant effects on Zn distribution in plant. The results indicate that Fe-deficiency increases the uptake, transport and distribution of Cd by cucumber seedlings.
国家科技期刊平台
NSTL
万方数据
维普
