水稻镉高积累材料的筛选及其镉积累特征研究

Screening of Rice Cultivars with High Cadmium Accumulation and Its Cadmium Accumulation Characteristics

由于当前土壤Cd污染问题日益严重,筛选获得水稻Cd高积累材料,研究水稻Cd高积累材料对Cd的积累特征,为Cd污染农田修复提供理论依据。采用Cd污染农田土壤进行大田试验,以56份水稻材料为研究对象,以水稻地上部生物量和Cd含量为筛选指标,筛选出水稻Cd高积累材料,并分析其Cd积累特征。(1)当大田土壤Cd含量为13.89 mg·kg-1时,56份水稻材料地上部Cd含量和Cd积累量在分蘖期(变异系数CV=44.05%和变异系数CV=50.21%)和孕穗期(变异系数CV=23.57%和变异系数CV=28.62%)均存在极显著差异。(2)以分蘖期和孕穗期水稻地上部Cd积累量、生物量和富集系数为筛选指标,采用聚类分析方法,当聚类距离为14.62(分蘖期)和12.48(孕穗期)时,将水稻材料按Cd积累能力由高到低划分为Cd高积累材料、Cd中积累材料和Cd低积累材料。(3)Cd高积累材料地上部和整株生物量在分蘖期和孕穗期均显著大于Cd中积累材料,其在孕穗期地上部和整株生物量分别达835.66和994.59 g·m-2。Cd高积累材料地上部Cd积累量在孕穗期显著高于Cd中积累材料和Cd低积累材料;其整株Cd积累量在分蘖期和孕穗期均显著高于Cd中积累材料和Cd低积累材料。(4)Cd高积累材料在分蘖期和孕穗期富集系数和转移系数均大于Cd中积累材料和Cd低积累材料。通过筛选得到的水稻Cd高积累材料(GR泸17/548//泸17_9、GR548/明63//527_1、GR泸17/IRBN95-199_1、GR泸17/548//泸17_7、GR泸17/IRBN92-332//泸17_1、GR泸17/548//泸17_3、GR泸17/IRBN92-332//527_8)具备Cd富集植物的特征,可用于Cd污染农田土壤的修复。

Abstact:With the development of agriculture and industry, a large number of pollutants containing cadmium turning into the soil. It is important to screen the rice cultivars with high-Cd accumulation and study to its accumulating characteristics. Field experiment was conducted to investigate the differences of 56 rice parent materials on Cd accumulation characteristics under pollution paddy field. High-Cd accumulation rice cultivars were screened by the Cd content and shoot biomass, then analyzed its accumulation characteristics. (1) There were significant differences in the Cd content and Cd accumulation for rice cultivars at tillering stage (CV=44.05% and CV=50.21%) and booting stage (CV=23.57% and CV=28.62%) among the 56 rice cultivars when the Cd concentration of soil was 13.89 mg·kg-1. (2) The 56 rice cultivars were classified into tree type: high Cd accumulation type, mean Cd accumulation type and low Cd accumulation type. (3) The shoots and whole plants biomass of high Cd accumulation type were significantly higher than mean Cd accumulation type at tillering and booting stages. Then, the shoots and whole plants biomass of high Cd accumulation type reached 835.66and 994.59 g·m-2 which was higher than mean Cd accumulation type. The Cd accumulation in shoots were significantly higher than mean Cd accumulation type and low Cd accumulation type at booting stage. Meanwhile, the Cd accumulation in whole plants were significantly higher than mean Cd accumulation type and low Cd accumulation type at tillering and booting stage. (4) The Cd bioaccumulation coefficient and translation coefficient of high Cd accumulation type were significantly higher than mean Cd accumulation type and low Cd accumulation type at booting stage. These results suggested that high Cd accumulation type (GR Lu 17/548//Lu 17_9, GR548/Ming 63//527_1, GR Lu 17/IRBN95-199_1, GR Lu 17/548//Lu 17_7, GR Lu 17/IRBN92-332//Lu 17_1, GR Lu 17/548//Lu 17_3, GR Lu 17/IRBN92-332//527_8) were typical Cd hyperaccumulator, and can be used in phytoremediation of Cd contaminated soil.