重金属（Hg，As，Pb）污染对蚕豆根尖细胞微核的诱变研究

采用蚕豆根尖细胞微核检测技术，分别探讨不同浓度的HgCl2、As2O3、Pb（NO3）2对蚕豆根尖细胞微核率的影响。以蒸馏水处理作为阴性对照实验。结果表明不同浓度的HgCl2可使蚕豆根尖细胞微核率明显上升，说明HgCl2对蚕豆根尖具有明显的毒性效应——诱发突变（微核）。不同浓度As2O3可使蚕豆根尖细胞微核率明显上升。说明三氧化二砷（As2O3）对蚕豆根尖具有明显的毒性效应——诱发突变（微核）。蚕豆根尖微核率在铅离子浓度0—25mg／L范围内，随着硝酸铅处理浓度的升高而升高，说明硝酸铅是一种较强的诱变剂。

Study of Cytogenetic Toxic Effect of Heavymetal(Hg,As,Pb)Pollution on the Rate of Micronucleus of Vicia Faba Root Tip Cells

The micro - nuclear test in Vicia Faba root tips cell was utilized to study the toxic effects of different concentrations of HgCl2 ,As2O3 ,Pb（ NO3 ） 2 on the micronucleus frequency of Vicia Faba root tip ceils . Distilled water was used as a negative control. Results shows that the different concentration of HgCl2 could induce high frequency of micronucleus, and HgCl2 had cyto- genetic toxic effect on the root tip cells of Vicia Faba. While the different concentration of As2O3 could also induce high frequency of micronucleus, which means that As2O3 had cytogenetic toxic effect on the root tip cells of Vicia Faba. Micronucleus rate of root tip cells of vicia faba was increased with the elevation of Pb（ NO3 ）2 concentration within the range of 0 -25 mg/L, and Pb （NO3） 2 was therefore regarded as a strong mutagen.