Abstract: Selenium (Se) and silicon (Si) have active roles in reducing Cd uptake in plants. Taking hybrid cultivars Yixiang 2115 with low-Cd accumulation in grain and Chuanguyou 2348 with high-Cd accumulation in grain as material, this study carried out field experiment to investigate the effects of Se, Si and their mixed treatment on Cd and mineral element concentrations of these 2 rice cultivars. The results showed that Se and Si treatments had significant effects on the contents of Cd, Ca, Cu, Mn, Zn, Se and Si in rice stem, leaf, ear and brown rice. The the contents of Cd, Ca, Cu, Mn, Zn in Chuanguyou 2348 were much higher than that in Yixiang 2115, except Se and Si. Se and Si could reduce Cd, Cu and Mn contents in Yixiang 2115 stem, Cu contents in panicle of Yixiang 2115, and Cd content in leaf blade of  Chuanguyou 2348; and increased Ca contents in leaf blades of both varieties and in Chuanguyou 2348 stem. Si + 6 μmol/L Se treatments significantly reduced Zn content in stem and Cd content in leaf blades of Yixiang 2115, Mn accumulation in stem and Ca content in panicle of Chuanguyou 2348; stimulated the increase of Cu, Zn contents in leaf blades of Yixiang 2115. Si +12 μmol/L Se treatment suppressed the accumulation of Cd, Zn in Chuanguyou 2348 stem and Zn accumulation in panicle of Yixiang 2115, and stimulated the accumulation of Cu in stem and Mn, Zn in panicle of Chuanguyou 2348. All Se and Si treatments decreased Cd contents in Yixiang 2115 panicle, but with 12 μmol/L Se treatment the decreasing range of Cd content in Chuanguyou 2348 panicle, became small and even changed to slightly increase. Under single 6 μmol/L Se treatment, brown rice of Yixiang 2115 had the minimum Cd concentration, while Chuanguyou 2348 got the minimum Cd contents in brown rice under Si + 6 μmol/L Se and 12 μmol/L Se treatments.

Key words: hybrid rice, cadmium stress, combined application of selenium and silicon, mineral element

摘要： 硒（Se）、硅（Si）在减少植物对Cd的吸收方面有着积极作用。以籽粒低镉积累杂交籼稻宜香2115和籽粒高镉积累杂交籼稻川谷优2348为材料进行大田试验，研究Se、Si及其配施对杂交籼稻Cd及矿质营养元素含量的影响。结果表明：Se、Si对水稻茎、叶、穗和糙米中Cd、Ca、Cu、Mn、Zn、Se和Si含量有显著影响。川谷优2348中Cd、Ca、Cu、Mn和Zn含量均显著高于宜香2115，Se和Si含量则低于后者。Se、Si降低宜香2115茎秆Cd、Cu、Mn含量、穗部Cu含量及川谷优2348叶片Cd含量，增加了两个品种叶片及川谷优2348茎秆中Ca含量。Si+6 μmol/L Se处理显著降低宜香2115茎秆中Zn、叶片中Cd、川谷优2348茎秆Mn以及穗部Ca含量，促进宜香2115叶片Cu、Zn含量的升高；Si+12 μmol/L Se处理抑制川谷优2348茎秆Cd、Zn和宜香2115穗部Zn的积累，促进川谷优2348茎秆中Cu和穗部Mn、Zn的积累。所有Se、Si处理均降低宜香2115穗部Cd含量，但高浓度Se处理下川谷优2348穗部Cd含量下降幅度变小甚至略升。宜香2115在单施6 μmol/L Se下糙米Cd含量最低，川谷优2348则在Si+6 μmol/L Se和12 μmol/L Se下糙米Cd含量最低。

关键词: 杂交水稻, 镉胁迫；硒、硅配施；矿质元素