尼罗罗非鱼与萨罗罗非鱼回交一代与回交二代群体遗传特征的微卫星分析  

Genetic characteristics of the first and the second backcross generations of Oreochromis niloticus and Sarotherodon melanotheron by microsatellite maker analysis

作　　者：吴俊伟[1] 筴金华 张艳红 任炳琛 罗明坤[1] 梁从飞[1] 赵岩[1] 赵金良[1] 

机构地区：[1]上海海洋大学农业部淡水水产种质资源重点实验室,上海201306 [2]中捷国家级罗非鱼良种场,河北沧州061108

出　　处：《淡水渔业》2015年第4期10-14,共5页Freshwater Fisheries

基　　金：现代农业产业技术体系专项资金(CARS-49-4B);上海高校知识服务平台项目(ZF1206)

摘　　要：利用尼罗罗非鱼(Oreochromis niloticus)第二代遗传连锁图谱中微卫星标记,对尼罗罗非鱼♀与萨罗罗非鱼(Sarotherodon melanotheron)回交一代(BC1)和回交二代(BC2)群体遗传特征进行了分析。结果表明,从28个微卫星位点中筛选出9个在尼萨回交一代和回交二代中存在差异的扩增位点,这些多态性位点可作为尼萨回交一代和回交二代群体遗传鉴别的重要依据。尼萨回交一代群体的平均观测杂合度为0.670,多态信息含量为0.423;回交二代群体的平均观测杂合度为0.460,多态信息含量为0.365,回交二代群体的遗传多态性低于回交一代群体。与回交一代相比,尼萨回交二代群体的平均有效等位基因数较为一致(BC1:Ne=2.17,BC2:Ne=2.20),基因型数较为一致,但纯合基因型比例、优势等位基因频率均有明显提高,表明连续回交导致后代遗传同质性提高。This study conducted an analysis of genetic characteristics of the first and the second backcross generations from Oreochromis niloticus and Sarotherodon melanotheron by microsatellite makers from the 2nd genetic linkage map of Oreochro-mis niloticus.The results showed there were 9 loci with different-sized alleles between the first and the second backcross generations detected from 28 pairs of microsatellites, these highly polymorphic loci could be used as their genetic identifica-tion makers.The average observed heterozygosity and polymorphism information was 0.670 and 0.423 in the first back-cross generation, and 0.460, 0.365 in the second backcross generation, respectively.The polymorphism of the second backcross generation was lower than that of the first backcross generation.In comparison with the first backcross genera-tion, the second backcross generation possessed the approximate number of alleles and genotypes; however, the proportion of homozygous genotype and predominant allele frequency in the second backcross generation improved significantly, which showed the increase of genetic homogeneity in the second backcross generation was caused by continuous backcrossing.

关 键 词：尼罗罗非鱼(Oreochromis niloticus) 萨罗罗非鱼(Sarotherodon melanotheron) 回交后代 遗传特征 微卫星标记 

分 类 号：S917.4[农业科学—水产科学]