Cd对不同品种水稻微量元素累积特性及其相关性的影响

采用土培盆栽试验方法,以东北地区大面积种植的32个水稻品种为试验材料,在土壤中未添加(0 mg·kg-1Cd)和添加Cd(5 mg·kg-1 Cd)的条件下,研究不同品种水稻籽粒、颖壳、茎叶和根系中Cd、Fe、Mn、Cu、Zn、Si几种微量元素的累积分布特征以及它们之间的相关关系.结果表明,几种微量元素在根系和茎叶中的含量大于籽粒和颖壳,其中Cd、Fe在根系和茎叶中的累积远远高于其他元素.水稻不同部位各微量元素之间大多数表现为正相关关系,加Cd处理后元素之间的相关性变得更明显,尤其是籽粒中Cd与其他元素之间从未加Cd时不相关到加Cd后达到极显著相关水平.从微量元素含量来看,3号品种(越路早生)籽粒中Cd和其他有益微量元素含量相对较低,而8(千重浪-1)和27(吉03-2843)号品种含量较高.从营养价值和食品安全角度综合考虑,在无污染的农田土壤上,宜选择3、8、27号作为理想的水稻品种.

Influence of Cd on Microelements Accumulation and Their Correlation in Different Rice Cultivars of Northeastern China

A soil pot experiment was conducted to investigate the influence of Cd on several microelements accumulation and their correlation in different parts of 32 rice cultivars,which collected from Northeastern China.Two uniform rice seedlings cultivated previously were selected and transplanted to soil amended with 0 mg·kg-1 or 5 mg·kg-1Cd(as 3CdSO4·8H2O) in May 26 and harvested in September 30 in 2009.After harvest,the concentrations of Cd、Fe、Mn、Cu、Zn and Si were determined in root,shoot,glume and grain of rice.Results showed that concentrations of these microelements in root and shoot were higher than those in glume and grain,especially for Cd and Fe.In most cases,the relationship between elements showed positive correlation,which was intensified in treatment supplied with 5 mg·kg-1 Cd.Especially in grain,concentrations of Cd and other microelements showed significant positive correlation at Cd5 treatment,whereas no correlation was observed at Cd0 treatment.In general,the cultivars with higher Cd concentrations in grain also contained higher concentrations of microelements,such as Qianchonglang-1(8) and J 03-2843(27),whereas the cultivars with lower Cd concentrations in grain had lower microelements concentrations,such as Yueluzaosheng(3).Concerning the nutritive value and food safety of rice grain,Yueluzaosheng(3),Qianchonglang-1(8) and J 03-2843(27) were recommended to plant in non-polluted agriculture soils.