Liu Jianguo, Qian Min, Cai Guoliang, Yang Jianchang, Zhu Qingsen
Department of Environmental and Safety Engineering, Jiangsu Polytechnic University, Changzhou, Jiangsu 213016, China.
J Hazard Mater. 2007 May 8;143(1-2):443-7. doi: 10.1016/j.jhazmat.2006.09.057. Epub 2006 Sep 23.
The variations among six rice cultivars in cadmium (Cd) uptake and translocation were investigated with pot soil experiments. The results showed that only a very small portion (0.73%) of Cd absorbed by rice plant was transferred into grain. With regard to plant total Cd uptake, Cd concentrations and quantity accumulations in roots, stems and leaves, the differences among the cultivars (between the largest one and the smallest one) were less than one time. But for Cd concentrations and Cd quantity accumulations in the grains, the differences were more than five and eight times, respectively. With respect to Cd distribution portions in plant organs, the diversities among the cultivars were also small in roots, stems and leaves, but much larger in grains. Grain Cd concentrations correlated positively and significantly (P<0.01) with Cd quantity accumulations in plant, Cd distribution ratios to aboveground parts, and especially with Cd distribution ratios from aboveground parts to the grain. The results indicated that Cd concentration in rice grain was governed somewhat by plant Cd uptake and the transport of Cd from root to shoot, and in a greater extent, by the transport of Cd from shoot to grain. Cd was not distributed evenly in different products after rice grain processing. The average Cd concentration in cortex (embryo) was five times more than that in chaff and polished rice. With regard to Cd quantity accumulation in the products, near 40% in cortex (embryo), 45% in polished rice and 15% in chaff averagely.
通过盆栽土壤试验研究了6个水稻品种对镉（Cd）吸收和转运的差异。结果表明，水稻植株吸收的Cd只有很小一部分（0.73%）转移到籽粒中。就植株对Cd的总吸收量、根、茎和叶中Cd的浓度及积累量而言，品种间（最大与最小之间）差异不到1倍。但籽粒中Cd浓度和Cd积累量的差异分别超过5倍和8倍。就Cd在植株器官中的分配比例而言，品种间在根、茎和叶中的差异也较小，但在籽粒中的差异较大。籽粒Cd浓度与植株Cd积累量、地上部Cd分配比例呈极显著正相关（P<0.01），尤其与地上部到籽粒的Cd分配比例呈极显著正相关。结果表明，水稻籽粒中的Cd浓度在一定程度上受植株对Cd的吸收及Cd从根向地上部转运的影响，在更大程度上受Cd从地上部向籽粒转运的影响。水稻籽粒加工后不同产品中Cd分布不均。皮层（胚）中Cd平均浓度是谷壳和糙米的5倍。就产品中Cd积累量而言，皮层（胚）中平均约占40%，糙米中占45%，谷壳中占15%。
