芸苔属蔬菜的Cd富集特性及其修复土壤Cd污染的潜力

通过温室水培13个小白菜和11个结球甘蓝品种,研究其对重金属镉(Cd)的富集特性.结果表明,在0(CK)、25、50、125、250μmol·L-15个不同Cd供应浓度下,不同芸苔属蔬菜品种的地上部Cd含量之间差异达极显著水平;且随Cd浓度的升高,不同品种对Cd的富集呈现一定规律:即单峰富集型、双峰富集型和递增型.以生物富集因子(BCF)为指标进行分析,则可分为2种类型:递减型和单峰型,前者BCF随Cd供应浓度升高而减小,最高BCF为146.85(品种Invinto);后者BCF随Cd供应浓度升高而升高,在50μmol·L-1出现一个峰值,随后BCF下降,最高BCF峰值达到72.95(品种94-N1).可见BCF是筛选修复土壤Cd污染植物材料的较为合适的指标.在本试验条件下,筛选出小白菜品种福绿1号、94-N1、日本华冠、日本冬妃、虹桥矮青和结球甘蓝品种Ducati、Matsumo、Gideon、Invinto可作为潜在修复土壤Cd污染的植物材料.

Cd-accumulation characteristics of Brassica cultivars and their potential for phytoremediating Cd-contaminated soils

Cd-accumulation characteristics of 13 Brassica chirensis cultivars and 11 B.oleracea cultivars were investigated. The results showed that there was extremely significant difference (P<0.001) between Cd contents in the shoot of different cultivars under 5 Cd concentrations (i.e. 0, 25, 50, 125 and 250 μmol·L~(-1)) supplied in water culture. There were three types of shoot Cd concentration among different cultivars with the increase of Cd supply, which were single-peak, double-peak and constantly-increasing. While taking bioconcentration factor (BCF) as index, however, there were only two types, namely constantly-decreasing and single-peak. In the former type, taking the cultivar Invinto as an example, the highest BCF was 146.85, and it decreased with the increase of Cd supply. In the latter type, taking the cultivar 94-N1 as an example, with the increase of Cd supply, BCF increased and reached the peak value 72.95 while Cd concentration being at 50 μmol·L~(-1), then decreased. It was concluded that BCF is more appropriate index than Cd content in shoot for screening the plant materials for phytoremediating Cd-contaminated soil, and cultivars Fulu No.1, 94-N1, Japanese Huaguan, Japanese Dongfei, Hongqiaoaiqing of B.chirensis and Ducati, Matsumo, Gideon, Invinto of B.oleracea are the potential materials for phytoremediating Cd pollutant in soil under our experimental condition.