为了指导团头鲂（、回交F₂的育种工作，对两种回交F₂、一种杂交F₂及两种原始亲本共5个群体的遗传结构及生长性能进行研究。结果表明，团头鲂（MA）、翘嘴鲌（CA）、团头鲂♀×翘嘴鲌2）、翘嘴鲌♀×MC）分别为4.50、4.40、4.75、4.85、5.10，平均观测杂合度（e）分别为0.6671、0.6308、0.6995、0.7240、0.6949，平均多态信息含量（PIC）分别为0.6046、0.5717、0.6406、0.6676、0.6339，BC1-F₂群体的遗传多样性最高（群体大多数位点的Hardy-Weinberg平衡遗传偏离指数显示杂合子过量（2首先聚类，MA与BC1-F₂首先聚类再与MC-F₂聚类，最后这2大类聚为一支。结合Nei’s遗传距离和遗传相似度分析，其杂交与回交后代均具有母本效应。引物Me.Am._15、Me.Am._1、TTF01、Mam25在5个群体中均产生特异性条带，可作为5个群体的鉴定标记。通过对5个群体的生长性能的测量，BC1-F₂群体表现出显著的生长优势。该结果对鲂鲌杂交及回交后代的种质资源保护、种群鉴定及良种的选育具有重要意义。

To guide the breeding of (CA), one hybrid F₂[)], two backcross F₂[(BC1-F₂) and (BC2-F₂)] and their parents were analyzed using twenty microsatellite markers. The mean number of alleles (, and BC2-F₂ were 4.50, 4.40, 4.75, 4.85, and 5.10, respectively. The mean values of observed heterozygosity () were 0.7683, 0.5550, 0.7967, 0.8317, and 0.6200, respectively. The mean values of expected heterozygosity () were 0.6671, 0.6308, 0.6995, 0.7240, and 0.6949, respectively, and the average polymorphism information contents (PIC) were 0.6046, 0.5717, 0.6406, 0.6676, and 0.6339, respectively. The mean Hardy-Weinberg indices of MA, MC-F₂, BC1-F₂ displayed a heterozygote excess, whereas the gynogenetic populations (CA and BC2-F₂) showed a heterozygote deficit. The unweighted pair-group method with arithmetic means (UPGMA) showed that the CA and BC2-F₂ populations first grouped together, and then MA and BC2-F₂ grouped together, and then they clustered with MC-F₂. According to the genetic identity analysis, F₂ hybrids and backcross F₂ groups showed maternal effects. Particularly, the microsatellite primers Me.Am._15, Me.Am._1, TTF01, and Mam25 identified five groups. Growth performances of the five groups were analyzed further, and BC1-F₂ groups were found to have the most significant growth advantage. Our results provide important information for the breeding, germplasm resources preservation, and germplasm identification of hybrid F₂ (M. amblephala♀×(M. mblycephala♀×]. To cultivate hybrid strains with fast growth characteristics without adversely affecting the genetic background of the same or similar fish species in natural waters, backcrossing is a feasible method. This paper found that backcrossing could not only improve the superiority of varieties and facilitate correct selection, but also accelerate the stability of the heritability of hybrid offspring, reduce the separation of offspring, and make the heritability of hybrid offspring similar to that of the parent. Therefore, the backcross method lays a genetic foundation for artificial gynogenetic transgenic fish.

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国家自然科学基金项目（31572220）；国家科技支撑计划项目（2012BAD26B00）；上海地方高校能力建设项目（18050501900）