皱纹盘鲍人工育苗的初步研究

为探讨近三十年来我国皱纹盘鲍养殖模式对群体遗传结构产生的影响，利用线粒体细胞色素C氧化酶亚基 (COⅠ)基因和细胞色素b (Cytb)基因分析了定殖漳州的群体、大连培育蓬莱越冬群体、荣成培育福建越冬群体及长山列岛 (砣矶岛、大钦岛、南隍城岛)皱纹盘鲍群体的遗传多样性与群体遗传结构。结果显示，在259个个体730 bp的COⅠ序列片段中检测到48个变异位点和30个单倍型，6个群体的单倍型多样性为0.586~0.897，核苷酸多样性为0.0056~0.0081。259个个体730 bp的Cytb序列片段中检测到59个变异位点和32个单倍型，6个群体的单倍型多样性为0.605~0.909，核苷酸多样性为0.0077~0.0120。基于COⅠ和Cytb基因的群体间F_st值以及AMOVA结果表明，绝大部分群体之间存在显著的遗传分化，并且遗传变异主要来源于群体内。现行的皱纹盘鲍北鲍南养模式加强了不同群体之间的基因交流，使不同遗传背景的种群二次接触，导致皱纹盘鲍6个群体均具有较高的单倍型多样性和核苷酸多样性；而各养殖群体中的不同选育条件则可能是造成显著遗传分化的重要原因。本研究对分属南北沿海的6个皱纹盘鲍群体的遗传评估将为我国皱纹盘鲍资源的合理利用以及养殖模式对遗传结构的影响提供科学依据。

A preliminary study on the artificial rearing of the larvae and juveniles of Haliotis discus hannai ino

Pacific abalone (Haliotis discus hannai) is an important marine shellfish in China, which is naturally distributed in the coastal areas of Shandong Peninsula and Liaodong Peninsula, and has high economic and nutritional value. Since the 1990s, with the extensive application of hybridization technology, the cultivation industry of H. discus hannai has gradually moved from northern to southern China and developed rapidly. In 2019, the production of H. discus hannai and its hybrid offsprings in China has reached 180 000 tons. However, the process of artificial breeding and selection may reduce the genetic diversity index of species, change the genetic structure, or even cause genetic differentiation of populations. In order to explore the possible effects of cultivation patterns on the genetic structure of Pacific abalone in China in the last 30 years, 259 individuals were collected from Dalian (DL), Rongcheng (RC), Zhangzhou (ZZ), Tuoji Island (TJ), Daqin Island (DQ), and Nanhuangcheng Island (NH) , the last three island belonging to the Changshan Archipelago of China. The mitochondrial cytochrome C oxidase subunit (COⅠ) gene and cytochrome B (Cytb) gene sequences were amplified by polymerase chain reaction (PCR) and sequenced on an automatic sequencer by using forward and reverse primers. Bioedit 7.0.5, DNAsp 5.10, MEGA 6.06 and Arlequin 3.5 software were used for sequence analysis. After sequence matching and shearing, 730 bp fragment length of COⅠ and Cytb genes were obtained. The results showed that 48 mutation sites and 30 haplotypes were detected in the 730 bp COⅠ sequence of 259 individuals; the haplotype diversity of the 6 populations ranged from 0.586 to 0.897, and the nucleotide diversity was 0.0056-0.0081; 59 mutation sites and 32 haplotypes were detected in the 730 bp Cytb sequence of 259 individuals. The haplotype diversity ranged from 0.605 to 0.909 and the nucleotide diversity was 0.0077-0.0120 in the 6 populations. The results of F_st and AMOVA among populations based on COⅠ and Cytb genes showed that there was significant genetic differentiation between most populations, and the genetic variation mainly existed between individuals but within populations. The current cultivation mode of H. discus hannai enhanced the gene exchange between different populations, and the secondary contact of populations with different genetic backgrounds resulted in high haplotype diversity and nucleotide diversity in all 6 populations. Different breeding standards in different breeding populations may be an important reason for the significant genetic differentiation. The evaluation of genetic resources of six Haliotis discus hannai populations in the northern and southern China coasts conducted in this paper provides a scientific basis for the rational utilization of the resources in China and the influence of breeding modes on genetic structure.