不同配方含硒叶面肥对水稻富硒降镉的影响

【目的】探索不同配方含硒叶面肥对水稻的富硒降镉效应及适宜施用环境,为富硒降镉型叶面肥开发和利用提供参考。【方法】以喷施清水为对照(CK),配制4种配方的含硒叶面肥,分别在低硒中低度镉污染和富硒高镉污染的稻田中施用,水稻成熟后测定水稻精米中的硒含量和镉含量。【结果】在低硒中低度镉污染稻田中,不同配方含硒叶面肥对水稻精米均有富硒降镉效果,配方1~4处理水稻精米中的硒含量分别比CK增加57.3%、83.4%、27.1%和108.6%,镉含量分别比CK显著降低62.5%、88.6%、88.9%和86.1%(P0.05,下同)。在富硒高镉污染稻田中,配方1~4处理水稻精米中的硒含量分别比CK显著提高280.1%、422.1%、152.7%和503.2%,但不同配方含硒叶面肥处理水稻精米镉含量与CK无显著差异(P0.05)。【结论】在有氮、磷、钾营养元素存在且叶面肥呈酸性的条件下,含硒叶面肥对水稻精米的富硒效果最佳,而硫酸锌和硫酸镁的存在可能降低其富硒效率。在低硒中低度镉污染的稻田中施用含硒叶面肥能显著降低水稻精米中的镉含量,但在富硒高镉污染的稻田中施用并无降镉效果。

Effects of different foliar fertilizers containing Se on Se-enrichment and Cd-reduction in rice

Objective]The effects of different formulas of foliar fertilizer containing selenium(Se) nutrition on Se-en-richment and Cd-reduction in rice and suitable application environment were studied to provide reference for product deve-lopment and utilization of Se-enrichment and Cd-reduction foliar fertilizers. Method]Spraying water was used as control (CK), four foliar fertilizers containing Se were prepared. They were used in low Se and medium-and-low cadmium(Cd) polluted field and rich Se and high Cd polluted field. Se and Cd contents in polished rice were measured after rice harvest.Result]In low Se and medium-and-low Cd polluted field, all formulas of foliar fertilizer containing Se could enrich Se content and reduce Cd content in polished rice. Compared to CK,formula 1-4 improved Se content in polished rice by 57.3%, 83.4%, 27.1% and 108.6% respectively;and significantly reduced Cd content in polished rice by 62.5%, 88.6%, 88.9% and 86.1%(P<0.05,the same below) respectively. In rich Se and high Cd polluted field,compared to CK, formula 1-4 improved Se content in polished rice by 280.1%,422.1%,152.7% and 503.2% respectively. But Cd contents in polished rice of different treatments presented insignificant difference compared with CK(P>0.05). Conclusion]When foliar ferti-lizer is acid and containing nitrogen, phosphorus and potassium, foliar fertilizers containing Se has the optimal Se-enrich-ment effects for polished rice. However, foliar fertilizer containing zinc sulfate and magnesium sulfate can reduce its effi-ciency on Se-enrichment in rice. In low Se and medium-and-low Cd polluted field, foliar fertilizer containing Se can reduce Cd content in polished rice significantly; but it has no such effect on rich Se and high Cd polluted field.