基于AFLP分析的乌江四川裂腹鱼种群遗传结构及多样性研究

本研究采用扩增片段长度多态性(AFLP)分子标记技术,以筛选出的7对引物,对采自贵州乌江的30尾四川裂腹鱼(Schizothorax kolzovi)的遗传结构和多样性进行分析.结果显示,用7对引物获得的扩增片段数为5～73,扩增片段长度范围为69～500bp,共检出扩增位点856个.其中,多态位点796个,占扩增总位...

AFLP analysis of genetic structure and diversity in population of Schizothorax kolzovi from the Wujiang River

Schizothorax kolzovi, which belongs to Cypriniformes, Cyprinidae and Schizothoracinae, is a wild fish species of high economic value, distributed in the Jinsha, Yalong, and upper Wujiang Rivers of the Yangtze River system and the Beipan River in the Pearl River system in China. To assess the genetic diversity and germplasm resources of S. kolzovi in the Wujiang River, Guizhou, the genetic structure and diversity were analyzed in the 30 individuals of the species from the river by the methods of amplified fragment length polymorphism (AFLP). With 7 pairs of selected primers through the pre-experiment, 5~73 DNA fragments were amplified in the 30 individuals, ranging from 69 to 500 bp. A total of 856 loci were detected, including 796 polymorphic loci accounting for 92.99% of the total. The population contained 30 genotypes, and the mean values of the observed number of alleles (Na), effective number of alleles (Ne), Nei diversity index (H), and Shannon information index (I) were 1.933 6, 1.338 8, 0.212 2, and 0.338 7, respectively. The genetic distance between individuals ranged from 0.169 1 to 0.531 9, with an average of 0.306 8. The unweighted pair group method with arithmetic mean (UPGMA) and neighbor-joining (NJ) phylogenetic trees of the 30 individuals contained 2 branches and had the similar topological structure. The S. kolzovi population in the Wujiang River contained rich genetic diversity. However, hydropower station dams, river pollution, and overfishing have reduced the distribution of S. kolzovi, and its population size has declined. Therefore, this species is ecologically threatened, and the population and germplasm resources of S. kolzovi in the Wujiang River needs to be protected.