不同中微量及有益元素对小麦吸收镉的影响

Effects of Secondary,Micro-and Beneficial Elements on Wheat Growth and Cadmium Uptake

采用盆栽试验,研究了不同中微量元素及有益元素对小麦生长和吸收Cd的影响。结果表明,与对照相比,硫酸钙、硫酸锰和氯化铜处理提高了小麦籽粒产量,而氯化镁、硫磺粉、硫酸铜、硫酸亚铁和硼酸处理却显著降低了小麦籽粒产量。在受Cd污染的土壤上施用不同中微量及有益元素肥料对土壤Cd的有效性具有一定的调节作用。镁、锰、铁、硼砂、硅酸钠和亚硒酸钠处理降低小麦对Cd的吸收;而钙、铜、锌和硼酸处理增加了小麦对Cd的吸收,特别是氯化钙。中量及微量元素的盐酸盐比硫酸盐处理促进小麦对Cd的吸收;小麦秸秆中Cd的积累量远远大于籽粒。因此,建议在Cd污染的旱作土壤上要避免施用硫磺粉、硼酸、氯化钙、锌肥和铜肥;施用铁、锰、镁肥及硼砂、硅酸钠和亚硒酸钠对降低土壤Cd的活性有明显效果,能在一定程度上降低小麦对Cd的吸收。

Effects of secondary,microand beneficial elements on wheat growth and cadmium （Cd） uptake were investigated in a pot experiment.The results showed that calcium sulfate,manganese sulfate and cupper chloride obviously increased wheat grain yield while magnesium chloride,elemental sulfur,cupper sulfate,ferric sulfate and boric acid significantly enhanced wheat grain yield compared to the CK treatment.On the cadmium （Cd） polluted soil,application of secondary,microand beneficial elements played a regulatory role on Cd availability.Among the fertilizers and elements studied,Mg,Mn,Fe,borax,sodium silicate and sodium selenite reduced Cd uptake,while Ca,Cu,Zn and boric acid promoted Cd uptake by wheat,calcium chloride in particular.The chlorides of the secondary and micro-elements favored Cd uptake more than their counterpart sulfates.The Cd accumulated in wheat straw was far more than in grain.Thus,it is suggested that on the Cd polluted upland soil it necessitates to avoid applying elemental sulfur,boric acid,Zn and Cu fertilizers,while application of Fe,Mn,Mg,borax,sodium silicate and sodium selenite can favor lowering the activity of soil Cd and depress Cd uptake by wheat to a certain extent.