中文摘要：

以蚕豆（Viciafaba）为对象、以菲为多环芳烃（PAHs）代表物开展彗星试验，用KometVersion6．0软件进行彗星图像分析，并选择评价参数研究PAHs污染的DNA损伤效应。以Olive尾动量（OTM）作为DNA损伤的评价参数，细胞彗星试验中蚕豆根尖DNA的损伤程度随菲质量浓度（0～0．6mg·L^-1）升高而显著增大。最高浓度组（0．6mg·L^-1）OTM值比阴性对照增加132．63％，存在剂量依赖性，表明菲能诱导蚕豆根尖DNA损伤。在培养液中菲质量浓度为0．1mg·L^-1条件下培养蚕豆，0—12h时DNA损伤程度随时间延长而增大，12h时OTM值为38．82＋4．48；12～24h时DNA损伤程度则随时间延长而趋小。为确定菲污染导致DNA损伤的途径，进行非细胞彗星试验，结果表明，0．05mg·L^-1菲即可造成显著DNA损伤（OTM值为22．27±0．42），且DNA损伤程度随菲浓度提高而增大。菲对蚕豆根尖细胞可能存在直接的DNA损伤效应。

英文摘要：

DNA damage of Vicia faba root tip cells caused by phenanthrene was investigated using the comet assay. The resulting comet image was analyzed using Software Komet Version 6. 0. Olive tail moment （OTM） was found to be the most preferable parameter to evaluate DNA damages. As observed in the cellular comet assay, the DNA damage of Vicia faba root tip ceils was aggravated with rising phenanthrene concentrations （0-0. 6 mg · L^-1） in solution. With a high concentration （0. 6 mg · L^-1） , the OTM increased by 132. 63% as compared with the control. An obvious phenanthrene dose-dependent relationship was observed for DNA damage. However, DNA damage by 0. 1 mg· L^-1 phenanthrene was time-dependent, aggravating with the passing time in the first 12 h and then mitigating in the second 12 h. In order to determine pathways of phenanthrene-caused DNA damage, direct effect of phenanthrene on Viciafaba root tip cell DNA was assessed with the acellular comet assay. It was found that phenanthrene at 0. 05 mg· L^-1 caused significant damage （ OTM 22. 27± 0.42） to Viciafaba root tip cell DNA and the damage aggravated with the increasing phenanthrene concentration （0-0. 6 mg · L^-1）.