寒地水稻分蘖盛期对镉的吸收与筛选研究

试验处理药剂为硫酸镉(3CdSO4·8H2O)和氯化镉(CdCl2·5/2H2O),镉处理浓度分别为0、0.5、1.0、2.0、5.0 mg/kg,采用土培盆栽方法研究12份水稻品种在分蘖盛期对镉的吸收特征差异。试验结果表明:根系含镉量受周围土壤镉含量影响较大,不能作为筛选低镉吸收水稻品种的鉴定指标;土壤中的镉含量只能作为筛选低镉吸收品种的间接指标,其镉残存量与处理浓度之间为二次回归关系,回归方程为y=-0.015x2+0.4001x+0.0874。植株体内镉含量,是最佳的可直接用于鉴定筛选低镉吸收品种的指标,处理浓度与植株体内含镉量呈极显著二次回归关系,回归方程为y=0.7431x2+0.3666x-0.0366。由间接和直接鉴定指标判定龙粳16、龙粳14、龙粳12及龙粳21为低镉吸收品种。

Study on Cadmium Absorption and Screening at Tillering Stage in Cold Rice

In this experiment, the treatment medicament were cadmium sulfate （3CdSO4· 8H2O） and cadmium chloride （CdCl2· 5/2H2O）, cadmium concentrations were 0, 0.5, 1, 2, 5 mg/kg, 12 rice varieties were used as material, the Cadmium absorption characteristics with potted soil experiment at tillering stage. The results showed that cadmium content of root was more affected by cadmium content of soil around, could not been used as a screening index for low cadmium absorption on rice variety. The cadmium content of soil been used as a screening indirect index for low cadmium absorption on rice variety, and there were two regression relationship between the residual quantity and concentration of cadmium, the regression equation was y=-0.015x2＋0.4001x＋0.0874. The cadmium content of plant was is directly used for screening low absorption of cadmium resistant index, there were significantly two regression between the treatment concentration and cadmium content, the regression equation was y=0.7431x2＋0.3666x-0.0366. Longjing-16, Longjing-14, Longjing-12 and Longjing-21 were low cadmium absorption varieties by indirect and direct identification index.