Genotypic variation in grain cadmium concentration of lowland rice
Genotypic variation in grain cadmium concentration of lowland rice
复制标题
DOI：
10.1002/jpln.200525101
复制
发表时间：
2006-10-01
影响因子：
2.5
通讯作者：
Jiang, Dean
中科院分区：
文献类型：
--
作者：
He, Junyu;Zhu, Cheng;Jiang, Dean
长江三角洲地区水稻土镉污染较为严重。水稻对镉的大量吸收及其向籽粒中的转移会给人类健康带来风险。镉吸收的基因型差异和镉在籽粒中的差异分配将是开发低粒镉水稻筛选或育种工具的基础。2002 ~ 2004年在浙江省嘉兴市试验场进行了长江三角洲地区38个不同类型水稻（籼、粳）基因型的田间试验。结果表明，镉污染土壤上种植的水稻基因型之间的稻草，糙米和谷壳镉浓度有很大的差异。糙米中镉的浓度范围为0.06至0.99毫克公斤（-1）。糙米对Cd的总吸收量在0.96 ~ 28.58 μ g/株之间。在一般情况下，籼型品种积累的镉显着高于粳稻型品种。稻草中Cd含量与糙米中Cd含量高度相关。虽然水稻基因型之间的镉分配比（%份额的总镉吸收糙米）显着差异，这些都没有与镉浓度的糙米。这表明水稻籽粒中Cd的积累主要受植株对Cd的吸收控制，而可能不是受Cd的差异分配控制。大的基因型变异表明通过基因型选择降低水稻镉含量的可能性。这种育种工具的发展应侧重于低镉吸收，而不是镉之间的稻草和粮食分配。
Cadmium (Cd) contamination of paddy rice soils is commonly observed in the Yangtse River Delta, China. Large Cd uptake by rice plants and its translocation into the grains can entail human-health risks. Genotypic variations in Cd uptake and a differential Cd partitioning into grains will be the basis for developing a rice screening or breeding tool for low grain Cd. A field experiment, conducted at the experimental farm of Jiaxing, Zhejiang province from 2002 to 2004, compared 38 rice genotypes of different types (indica vs. japonica) collected from the Yangtse River Delta. The results showed large differences in Cd concentrations in straw, brown rice, and grain chaff among the rice genotypes grown on Cd-contaminated soil. Concentrations in brown rice ranged from 0.06 to 0.99 mg Cd kg(-1). The total Cd uptake in brown rice varied between 0.96 and 28.58 mu g plant(-1). In general, indica-type cultivars accumulated significantly more Cd than the japonica-type cultivars. The Cd concentration in straw was highly correlated with that in brown rice. While significant differences in the Cd-partitioning ratio (% share of total Cd uptake found in brown rice) among rice genotypes were observed, these were not correlated with Cd concentration of brown rice. This indicates that the Cd accumulation in rice grains appears to be governed mainly by the Cd uptake by the plant and probably not by differential Cd partitioning. The large genotypic variation suggests the possibility to lower the Cd content of rice by genotype selection. The development of such breeding tools should focus on low Cd uptake rather than Cd partitioning between straw and grain.