不同基因型芥菜对5种重金属累积差异性研究

The Accumulation of Five Heavy Metals in Different Genotypes of Brassica juncea

探究不同基因型芥菜对镉(Cd)、砷(As)、铅(Pb)、汞(Hg)和铬(Cr) 5种重金属的累积差异性,为芥菜在重金属复合污染地区生产的安全性提供指导。通过盆栽试验研究9种不同基因型芥菜对5种重金属复合污染的响应差异,并结合重金属富集系数和转运系数以及单因子污染指数法、内梅罗综合污染指数法综合评价芥菜在重金属污染区的生产安全性。结果表明:芥菜具有较强的茎/叶重金属转运能力,重金属主要累积在芥菜根及叶中。芥菜不同部位重金属Cd的单项污染指数普遍较高且存在较大的品种差异。Pb、As、Hg和Cr污染指数呈现趋势类似,品种及不同部位间差异不明显。供试品种中‘五四青丕蓝’、‘脆嫩儿菜’、‘特大棒菜’、‘抗热四季甜竹芥’为较好的重金属低累积芥菜品种。芥菜对重金属的累积有基因型差异和重金属种类差异,通过筛选不同基因型芥菜可以获得生产上较为安全的品种。

The study aims to investigate the accumulation difference of five heavy metals: cadmium(Cd),arsenic(As), lead(Pb), mercury(Hg) and chromium(Cr) in different genotypes of brassica juncea, and to provide guidance on the production safety of brassica juncea in areas with complex contamination of heavy metals. Combining the heavy metal biological concentration factor and transfer factor with the single-factor contamination index method, as well as the Nemero integrated contamination method, the responses of nine different genotypes of brassica juncea to the five heavy metals were investigated in pot experiments to comprehensively evaluate the production safety of brassica juncea in heavy metal contaminated areas. The results show that Brassica juncea has strong ability to transfer heavy metals from stem to leaf, and heavy metals are mainly accumulated in the roots and leaves of brassica juncea. The individual contamination index of heavy metal Cd in different parts of brassica juncea is generally high and has large varietal difference. The contamination indexes between Pb, As, Hg and Cr show similar trend, and the differences between species and parts are not obvious. Among the varieties tested,‘Wusiqingpeilan’,‘Cuinengercai’,‘Tedabangcai’and‘Kangresijitianzhujie’are better brassica juncea varieties with ower heavy metal accumulation capacity. The accumulation of heavy metal in brassica juncea is related to genotype and heavy metal species, and it is feasible to select brassica juncea varieties with low accumulation of heavy metals which can be used for planting in heavy metal contaminated fields.