Instituto de Biotecnologia e Bioengenharia, centro de Genética e Biotecnologia da Universidade de Trás os Montes e Alto Douro (IBB/CGB-UTAD), Vila Real, Portugal.
J Appl Genet. 2010;51(1):67-72. doi: 10.1007/BF03195712.
Restocking and stock enhancement programs are now recognized as an important tool for the management of fishery resources. It is important, however, to have an adequate knowledge on the genetic population structure of both the released stock and the wild population before carrying out such programs. In this study, random amplified polymorphic DNA (RAPD) markers were applied to assess genetic diversity and population structure of wild and hatchery populations of the white seabream Diplodus sargus and the common two-banded seabream D. vulgaris (Sparidae). The estimated values for intrapopulation genetic variation, measured using the percentage of polymorphic loci (%P), Shannon index (H'), and Nei's gene diversity (h), showed high values for all populations. The percentage of genetic variation within D. sargus and D. vulgaris populations, based on coefficient of gene differentiation, reached 82.5% and 90% of the total genetic variation, respectively. An undeniable decrease in genetic variation was found in both hatchery populations, particularly in D. sargus, compared to the wild ones. However, the high values of variation within all populations and the low levels of genetic variation among populations did not indicate inbreeding or depression effects, thus indicating a fairly proper hatchery management. Nevertheless, the results of this study highlight the importance of monitoring the genetic variation of hatchery populations, particularly those to be used in restocking programs. The creation of a genetic baseline database will contribute to a more efficient conservation management and to the design of genetically sustainable restocking programs.
现在，重新放养和Stock Enhancement 计划被认为是渔业资源管理的重要工具。然而，在开展这些计划之前，必须充分了解放流种群和野生种群的遗传群体结构。本研究应用随机扩增多态性 DNA（RAPD）标记评估了野生和养殖的白鲷（Diplodus sargus）和普通二带鲷（D. vulgaris）（鲷科）的遗传多样性和种群结构。使用多态位点数（%P）、香农指数（H'）和 Nei 基因多样性（h）衡量的群体内遗传变异估计值显示，所有群体的遗传变异值均较高。基于基因分化系数，D. sargus 和 D. vulgaris 群体内的遗传变异百分比分别达到了总遗传变异的 82.5%和 90%。与野生种群相比，两个养殖种群的遗传变异均明显减少，特别是 D. sargus。然而，所有群体内的高变异值和群体间的低遗传变异水平并未表明存在近亲繁殖或衰退效应，因此表明养殖管理相当得当。尽管如此，本研究结果强调了监测养殖种群遗传变异的重要性，特别是那些将用于重新放养计划的种群。建立遗传基线数据库将有助于更有效地进行保护管理，并设计具有遗传可持续性的重新放养计划。
