仿刺参自然群体和养殖群体间遗传变异的微卫星标记研究

Microsatellites analysis of genetic variation between natural and culture populations of Apostichopus japonicus

应用微卫星DNA技术对仿刺参自然群体和养殖群体遗传多样性进行了研究。在经过筛选的9个座位中,每个座位检测到的等位基因数为4～12个。自然和养殖群体中,有效等位基因平均数分别为6.5556和5.8889,观测杂合度的平均值分别为0.6416和0.5635。根据群体中各座位等位基因频率计算出两群体间的遗传相似度为0.7970、遗传距离为0.2269。对两群体进行Hardy-Weinberg平衡检验发现,两群体在某些位点都出现了杂合子缺失现象,特别是养殖群体在位点Psj2022,其Hardy-weinberg遗传偏离指数达0.5164。结果表明,与自然群体相比,仿刺参养殖群体存在杂合度降低,遗传多样性下降的现象,这可能与人工养殖过程中,亲本群体较小,引起近交机会增加有关。应制定相应的渔业生产和管理措施加以保护,以使仿刺参养殖持续健康发展。

By using microsatellite DNA techniques, the studies were conducted on the genetic diversity between natural and culture population of Apostichopus japonicus. The number of alleles generated from each locus of 9 screened loci was 4-12. The mean values of effective alleles（ae） in the natural and culture population were 6. 555 6 and 5. 888 9, respectively. The mean expected heterozygosity （He） were 0. 764 1 and 0. 694 1, while the average observed heterozygosity （Ho） were 0. 641 6 and 0.563 5 in the natural and culture population, respectively. The results showed that the natural resource of Apostichopus japonicus in China had higher ge-netic diversity, whereas the hetreozygosity and proportion of polymorphic loci in culture population were descendent. This was possibly related to the smaller population in culture, leading to increase of inbreeding. It is suggested that adequate measures should be taken in culture produc-tion so as to protect genetic diversity of Apostichopus japonicus.