辽宁省5种不同基因型水稻对镉吸收差异的研究

Study on the difference of cadmium absorption in five rice genotypes of Liaoning Province

为对耐镉性强且低积累水稻品种的培育提供理论实践依据,在土壤外源添加镉的条件下,采用盆栽试验研究了辽宁省5个不同基因型水稻根系、茎叶、籽粒对镉吸收积累的差异,通过对分蘖期、抽穗期镉在茎叶各亚细胞组分含量的分析,探讨了产生差异的机理。结果表明,水稻各部位镉含量随外源添加镉浓度的增加而升高且存在显著的基因型差异。不同基因型水稻籽粒镉富集系数存在显著的差异,且随添加镉浓度的升高,籽粒镉富集系数有下降趋势,5个品种富集系数相对较高的是沈稻47和辽粳9号,相对较低的是辽星1号、沈农15和沈农315,其中沈农315在各处理下均最低,与其他品种存在极显著差异。随着水稻生长发育,抽穗期镉在茎叶亚细胞各组分的含量低于分蘖期,且总体呈现细胞壁最大,可溶性部分次之,细胞器最小的规律;镉在各亚细胞组分的含量和分配比例因基因型和生育期不同而异,镉耐性品种辽星1号、沈农15和沈农315细胞壁和可溶性组分的镉含量和分配比例高于敏感性品种沈稻47和辽粳9号,细胞器的镉含量则低于敏感性品种。

In order to provide theoretical and practical basis for breeding rice varieties with high tolerance to cadmium and low accumulation,a pot experiment was conducted with five rice genotypes of Liaoning Province under soil exogenous cadmium added conditions.The cadmium accumulation in different parts of rice plant were investigated,meanwhile the contents and distribution in subcellular fractions of rice were an-alyzed to further reveal the mechanism.Results showed that,the cadmium content in each part of rice was increased with increasing cadmi-um amount and the differences were significant;there were significant differences in cadmium accumulation coefficients in grain of rice geno-types,there was a downward tendency of the cadmium accumulation coefficient with increasing cadmium amount,among which Shendao 47 and Liaojing 9 were relatively high,while Liaoxing 1,Shennong 15 and Shennong 315 were low,and Shennong 315 was the lowest under all treatments;the cadmium content in subcellular fractions of stem and leaf at heading stage was lower than that at tillering stage,the cell wall was the largest,the soluble part was the second,and the organelle is the smallest.The content and distribution proportion in subcelluar frac-tions of rice were different among genotypes and growing stages,cadmium content and distribution proportion in the cell wall and soluble part of cadmium tolerance rice variety Liaoxing 1,Shennong 15 and Shennong 315 were higher than those of sensitive varieties Shendao 47 and Liaojing 9,organelles were lower than sensitive varieties.