大泷六线鱼放流群体与野生群体遗传多样性比较

基于线粒体DNA控制区高变区部分序列和4对微卫星标记，对大泷六线鱼放流群体及自然海域群体的遗传多样性与遗传差异进行了比较分析。线粒体DNA控制区序列分析的结果显示，413尾个体共检测到单倍型117种，其中仅Hap_3、Hap_7和Hap_17为共享单倍型，占总单倍型数目的2.5%；放流、野生群体特有单倍型分别为20种和66种，分别占总单倍型数的17.09%和56.41%，放流群体特有单倍型数明显低于野生群体；放流群体和野生群体核苷酸多样性分别为0.005 1~0.006 7和0.005 8~0.007 5，单倍型多样性分别为0.856 7~0.949 9和0.883 1~0.954 9，遗传多样性均较高。微卫星标记分析结果显示，放流、野生群体平均等位基因数(N_a)分别为13~44和13~27，平均多态信息含量为0.885 6和0.874 0，均具较高的遗传多态性；群体遗传结构分析结果表明，放流、野生群体间遗传分化水平较低。研究表明，山东近海大泷六线鱼放流群体与野生群体均具有较丰富的遗传多样性，且遗传结构未存在显著的群体分化。

Comparison of genetic diversity between the released population and the wild population of Hexagrammos otakii

The fat greenling (Hexagrammos otakii) is one of the most important commercial fishes found along northern coast of China, with fast growth rate, high nutritional value and wide consumer acceptance. In recent years, large-scale proliferation and release activities have been held to restore its natural resources. In order to analyze the genetic diversity and genetic differences between releasing population and natural population of H. otakii, mitochondrial DNA control region and four microsatellite markers were selected for assessment. Mitochondrial DNA control region results showed that the length of the first hypervariable region was 436 bp, and 117 haplotypes were observed in 413 H. otakii individuals, among which only Hap_3, Hap_7, Hap_17 were shared by different populations. Number of individuals in releasing population and wild population was 74 and 105, accounting for 46.54% and 41.34% respectively, and the nucleotide diversity in releasing population and wild population was 0.005 1-0.006 7, 0.005 8-0.007 5, while the haplotype diversity was 0.856 7-0.949 9 and 0.883 1-0.954 9, respectively. Both of them showed a high level of genetic diversity for releasing and wild populations. Microsatellite markers results showed that the average allele number (N_a) was 13-44, 13-27, and the average polymorphism information content (PIC) was 0.885 6, 0.874 0, respectively, which indicated that genetic polymorphism of releasing and wild population was moderately high; results of population genetic structure analysis showed that the genetic differentiation between released population and wild population was smaller, i.e. ata lower genetic differentiation level. In summary, rich genetic diversity existed in both populations, and there was no significant population differentiation in genetic structure, which indicates that the proliferation and release activities have no obvious genetic diversity impact on the wild population.