【摘要】 通过6个可数性状、10个可量性状及24个框架性状,比较分析了尼罗罗非鱼(Oreochromis niloticus♀)×萨罗罗非鱼(Sarotherodon melanotheron♂)杂交后代F1、F2形态性状的遗传与变异特征,方差分析结果表明,除臀鳍棘数相同外,杂交F1、F2的可数性状数目相近,位于尼罗罗非鱼与萨罗罗非鱼之间;杂交F1体长/全长、框架参数D3-5/全长、D6-8/全长、尾柄长/全长、D5-7/全长、D8-10/全长等参数显著大于萨罗罗非鱼,体厚/全长、体高/全长、D1-6/全长、D3-4/全长、尾柄高/全长等参数显著大于尼罗罗非鱼;杂交F2的16个可量、框架性状与杂交F1间无显著差异,而头长/全长、D5-6/全长、D7-8/全长、D9-10/全长等参数显著大于杂交F1,躯干长/全长、尾柄长/全长、D1-2/全长、D5-7/全长、D7-9/全长等参数显著小于杂交F1。聚类分析结果表明,杂交F2与杂交F1先聚为一类,再依次与尼罗罗非鱼、萨罗罗非鱼聚类。分别建立了不同群体的可数性状、可量与框架性状的判别公式,判别正确率高低依次为尼罗罗非鱼、萨罗罗非鱼>杂交F1>杂交F2;利用尼罗罗非鱼和萨罗罗非鱼的判别公式对杂交F1进行判别,被判入尼罗罗非鱼的比例较高(可数性状92.9%、可量与框架性状57.1%);利用尼罗罗非鱼、萨罗罗非鱼及杂交F1的判别公式对杂交F2判别,被判入杂交F1的比例较高(可数性状68.6%、可量与框架性状77.2%)。主成分分布图显示,杂交F1、F2均位于尼罗罗非鱼和萨罗罗非鱼之间,杂交F1与尼罗罗非鱼重叠分布较多,杂交F2分布重叠区域较F1分散。以上结果表明,尼罗罗非鱼♀×萨罗罗非鱼♂杂交F1形态性状介于亲本之间,遗传了双亲的形态特征,且有一定的偏母遗传;杂交F2大部分形态特征遗传了杂交F1,但也存在一定程度的变异。本研究旨在通过分析尼罗罗非鱼、萨罗罗非鱼2个杂交世代中亲子间形态性状的遗传规律,为罗非鱼杂交育种研究与生产利用提供基础资料和依据。更多还原

【Abstract】 Inheritance and variation of the morphological traits of F1 and F2 hybrids of Oreochromis niloticus ♀ × Sarotherodon melanotheron ♂ were comprehensively analyzed in six countable morphological parameters, 10 meristic parameters and 24 truss framework parameters. ANOVA showed that the countable parameters of the F1 and F2 hybrids were intermediate between these of O. niloticus and S. melanotheron, except for the same number of spines in the anal fin. For the meristic and truss framework parameters, the F1 hybrid was larger than S. melanotheron in body length/total length, truss parameter D3-5/total length, D6-8/total length, tail length/total length, D5-7/total length, and D8-10/total length. In addition, it was larger than O. niloticus in body width/total length, body height/total length, truss parameter D1-6/total length, D3-4/total length, and caudal peduncle height/total length. The F2 hybrid showed no significant difference with the F1 hybrid in 16 meristic and truss framework parameters; however, the F2 hybrid was larger than the F1 hybrid in head length/total length, truss parameter D5-6/total length, D7-8/total length, and D9-10 /total length, but smaller than the F1 hybrid in body length/total length, caudal peduncle length/total length, truss parameter D1-2/total length, D5-7/total length, and D7-9/total length. Cluster analysis indicated that the F2 hybrid stock was initially clustered with the F1 hybrid stock, then they were clustered with O. niloticus and S. melanotheron. Discriminant fomulations for the four stocks were developed with countable and measurable parameters, and the order of discriminant accuracy for these stocks was O. niloticus, S. melanotheron > F1 hybrid > F2 hybrid. More F1 hybrid individuals were assigned to O. niloticus(92.9% in countable formula, 57.1% in measurable formula) than S. melanotheron by the discriminant formula of O. niloticus and S. melanotheron. Most F2 hybrid individuals were assigned to F1 hybrids by the discriminant formula of O. niloticus, S. melanotheron and F1 hybrid(68.6% in countable formula, 77.2% in measurable formula). Principal component analysis showed that the scatter plots of the F1 and F2 hybrids were distributed between O. niloticus and S. melanotheron. The F1 hybrid showed more overlapping with O. niloticus, but the F2 hybrid also overlapped with S. melanotheron. The above results showed that the O. niloticus ♀× S. melanotheron ♂ F1 hybrid inherited the morphological traits of their parents with some maternal inheritance. The F2 hybrid inherited some morphological parameters from the F1 hybrid, but also showed some distinct variations in other parameters.更多还原