真鲷自然群体和人工繁殖群体的遗传多样性

采用RAPD技术对真鲷野生群体及人工繁殖群体各23个个体进行了DNA多态性检测。实验选取OPK组16个10 bp随机引物用于两群体的遗传多样性分析。在野生群体和人工繁殖群体中分别获得131和123条扩增片段，两群体的多态片段比例分别为62.60%和54.47%，平均杂合度分别为0.4786和0.3633，可见真鲷野生群体及人工繁殖群体的遗传多样性较为丰富，在选择育种和遗传改良方面具有较大的潜力。人工繁殖群体的多态片段比例和平均杂合度都低于野生群体，意味着在生产过程中要采取行之有效的管理保护措施以避免或减少遗传多样性水平的降低，确保真鲷增养殖业的可持续发展。

Genetic diversity in the wild and hatchery populations of Red Seabream(Pagrus major)

Random amplified polymorphic DNA (RAPD) technique was employed to detect the DNA polymorphism in each 23 individuals of the index samples from the wild and hatchery populations of Red Seabream. A total of 20 decamer arbitrary primers were used and 16 of them generated clear RAPD bands. Of them, 131 were obtained from the wild population and 123 from the hatchery population. The mean percentage of polymorphic fragments of wild population was 62.60% opposite to 54.47% in the hatchery population, while the average heterozygosity valued 0.4786 and 0.3633, respectively. The richer polymorphic bands and the higher value of average heterozygosity indicated higher genetic diversity level of this species and the great potential in piscatorial genetic improvement. The experiment revealed the fact that the percentage of polymorphic fragments and the value of average heterozygosity of the hatchery population were lower than those of the wild population. As a result, it implied that effective husbandry and management measures must be taken to avoid reduction of genetic diversity so as to enable the sustainable development of the mariculture.