三角鲂×翘嘴鲌、团头鲂×翘嘴鲌两种杂交后代微卫星遗传结构分析

摘要

To guide breeding of Megalobrama terminalis, Megalobrama amblycephala and Erythroculter ilishaeformis, two hybrids Megalobrama amblycephala×Erythroculter ilishaeformis, Megalobrama terminalis×Erythroculter ilishaeformis and their parents were analyzed using sixteen microsatellite markers. The mean value of number of alleles (Na) were 3.56, 3.63, 3.44, 4.00 and 4.31, respectively. The mean value of observed heterozygosity (Ho) were 0.3510, 0.3757, 0.3175, 0.3818, and 0.4079, respectively. The mean value of expected heterozygosity (He) were 0.6182, 0.6290, 0.5921, 0.6490 and 0.6825, respectively. And the average value of polymorphism information content (PIC) were 0.5354, 0.5367, 0.5258, 0.5785, and 0.6067, respectively. The average value of polymorphism information content (PIC) of two hybrid population were higher than their parent Megalobrama amblycephala, Megalobrama terminalis and Erythroculter ilishaeformis, indicating a high genetic diversity. The unweighted pair-group method with arithmetic means (UPGMA) showed that populations of the Megalobrama amblycephala and Megalobrama terminalis first grouped together, and that Megalobrama amblycephala♀×Erythroculter ilishaeformis♂ and Megalobrama terminalis♀×Erythroculter ilishaeformis♂ first grouped together, and then they clustered with the Erythroculter ilishaeformis. In addition, the farthest genetic distance (0.5204) was between Megalobrama amblycephala and Erythroculter ilishaeformis, and the nearest genetic distance (0.0853) was between Megalobrama amblycephala and Megalobrama terminalis. According to the genetic identity analysis, two hybirds groups showed the maternal effect. The alleles of two hybirds were from their parents based on genetic analysis. Particularly, microsatellite primers TTF3, TTF4, TTF10, and Mam25 identified 5 groups. Our results provide important value in breeding, germplasm resources preservation, and germplasm identification of Megalobrama terminalis×Erythroculter ilishaeformis and Megalobrama amblycephala×Erythroculter ilishaeformis.%为了指导三角鲂(Megalobrama terminalis)、团头鲂(Megalobrama amblycephala) 与翘嘴鲌(Erythroculter ilishaeformis)的杂交育种工作, 利用筛选出的16对微卫星引物, 比较分析了团头鲂、三角鲂、翘嘴鲌、团头鲂 ♀×翘嘴鲌♂、三角鲂♀×翘嘴鲌♂后代群体的遗传结构; 结果显示, 平均等位基因数(Na)分别为3.56、3.63、 3.44、4.00和4.31, 平均观测杂合度(Ho)分别为0.3510、0.3757、0.3175、0.3818和0.4079, 平均期望杂合度 (He)分别为0.6182、0.6290、0.5921、0.6490和0.6825, 平均多态信息含量(PIC)分别为0.5354、0.5367、 0.5258、0.5785和0.6067.杂交群体的平均多态信息含量均大于他们的亲本团头鲂、三角鲂和翘嘴鲌, 表明杂交亲群体的遗传多样性较高.聚类分析显示团头鲂与三角鲂首先聚类, 团头鲂♀×翘嘴鲌♂与三角鲂♀×翘嘴鲌♂首先聚类, 然后这2大类聚为一支, 最后与翘嘴鲌聚类.其中团头鲂与翘嘴鲌遗传距离最远, 为0.5204,团头鲂和三角鲂遗传距离最近, 为0.0853, 结合遗传相似度分析表明2种杂交子代均具有母本效应.基因型分析表明, 2种杂交后代的等位基因均来自于父母本.引物TTF3、TTF4、TTF10以及Mam25在5个群体中均可产生特异性条带, 可区分5个群体.研究结果对三角鲂×翘嘴鲌和团头鲂×翘嘴鲌的良种选育、种质资源保存以及种群鉴定具有重要意义.