湖南四种尾矿环境下的狗牙根遗传多样性的RAPD分析

Genetic diversity analysis of Cynodon dactylon(L.) Pers. from the four different tailing mines of Hunan by RAPD

选择湖南4种有代表性的有色金属尾矿地所生长的野生狗牙根作为研究对象,并以正常生境下的野生狗牙根作为对照,采用RAPD技术分析了这些特别环境下的狗牙根的遗传多样性。17条10个核苷酸长的引物用于PCR扩增,共得到432条DNA带。检测位点160个,其中多态位点134个,占83.75%。各个类群间的Jaccard相似系数平均为0.4475±0.0806,遗传距离平均为0.3825±0.0712。结果显示生长于这些不同尾矿环境下的狗牙根种群在遗传本质上均产生了明显的分化,完全可以根据其尾矿基质的不同而划分为不同的生态型或品种,甚至可能处理为新的变种。狗牙根种群具有丰富的遗传多样性,作为先锋植物可为尾矿的复垦提供更多的品种选择。

The genetic diversity level of the population of Cynodon dactylon(L.)Pers. from four main tailing mines in Hunan Province was determined by random amplified polymorphic DNA(RAPD)analysis. One sample of C. dactylon living in normal habitat from Xiangyang town of Hengnan County was used as comparing group. Seventeen 10mer oligonucleotide primers were used for DNA ampification,and 432 DNA bands were generated. Total 160 loci were detected,of which 134(83.75%)were polymorphic. The mean value of Jaccard's coefficient of similarity is 0.447 5±0.080 6 among the taxa,the mean value of genetic distance is 0.382 5±0.071 2. The result indicated that the high genetic diversity existed in the population of Cynodon dactylon distributed at the four different tailing minerals,and it is reasonable to divide them into four different ecotypes or varieties respectively,depending upon the type of tailing minerals. Therefore,Cynodon dactylon will give more options of the pioneer plants out for resurrection of the tailing mine based on its rich genetic diversity.