基于SSR标记的鲌鲂“先锋2号”、团头鲂及黑尾近红鲌的群体遗传分析

Genetic analysis of Megalobrama amblycephala(♀),Ancherythroculter nigrocauda(♂)and their hybrid F4 generation based on SSR markers

从黑尾近红鲌发表的46对微卫星引物中筛选出的11对多态性较高的引物,分析团头鲂(♀)和黑尾近红鲌(♂)及其杂交后选育的F4代,即鲌鲂“先锋2号”三个群体的遗传多样性和遗传结构。研究结果显示:这三个群体之间的平均等位基因数分别为4.182、4.273、4.273;平均有效等位基因数分别为2.482、2.803和3.080;平均观测杂合度分别为0.712、0.380和0.507;平均期望杂合度分别为0.579、0.474和0.656;多态信息含量分别为0.508、0.414和0.572。鲌鲂“先锋2号”与母本团头鲂的遗传距离为0.2709,小于与父本黑尾近红鲌的遗传距离(0.5381),在亲缘关系树状图上先与母本聚为一支。鲌鲂“先锋2号”从母本中获得较多的遗传物质,较双亲有丰富的遗传多样性和更高的基因杂合度。研究结果将为研究团头鲂和黑尾近红鲌杂交后代的遗传多样性,探索鲌亚科鱼类属间杂交育种后亲本与子代的亲缘关系和遗传规律提供理论依据。

Population genetic diversity and genetic structure were investigated in Megalobrama amblycephala(♀),Ancherythroculter nigrocauda(♂)and their hybrid F4\M.amblycephala(♀)and A.nigrocauda(♂)cross\〗using 11 pairs of high polymorphic primers selected from 46 pairs of SSR primers.The average number of allele(Na)was shown to be 4.182 in M.amblycephala,4.273 in A.nigrocauda and 4.273 in their F4 hybrids(Bofang“No2.Xianfeng”),the average number of effective allele(Ne)was found to be 2.482 in M.amblycephala,2.803 in A.nigrocauda and 3.080 in their F4 hybrids.The average observed heterozygosity(Ho)0.712 in M.amblycephala,0.380 in A.nigrocauda and 0.507 in their F4 hybrids.The average expected heterozygosity(He)0.579 in M.amblycephala,0.474 in A.nigrocauda and 0.656 in their F4 hybrids.There was polymorphic information content(PIC)of 0.508 in M.amblycephala,0.414 in A.nigrocauda and 0.572 in their F4 hybrids.The genetic distance between F4 and its female parent was 0.2709,smaller than that between F4 and its male parent(0.5381).The dendrogram of phylogeny revealed that the F4 hybrids were first clustered withtheir female parent,showing that the hybrid F4 generation got more genetic material from the female parent and had more genetic diversity and higher gene heterozygosity than their parents.The findings provide data support for the genetic diversity of the hybrid progenies of M.amblycephala and A.nigrocauda and a theoretical basis for exploring the genetic relationship between parents and their offspring after the intergenetic cross-breeding.