橙色莫桑比克罗非鱼和荷那龙罗非鱼的染色体核型分析

The karyotypes of Mozambique tilapia and Zanzibar tilapia

采用体腔注射PHA-空气干燥法对橙色莫桑比克罗非鱼(Oreochromis mossambicus)和荷那龙罗非鱼(O.hornorum)染色体数量、形态和核型进行了分析和比较。结果显示:两种罗非鱼的二倍体染色体数目均为2n=44,都具有1对特大的染色体,未发现中部着丝粒染色体对和异型染色体。两种罗非鱼的染色体组型形态基本相似,它们的核型公式为2n=44,6sm+24st+14t,NF=50,用常规染色体染色的方法难以区分。研究结果表明,这两种罗非鱼的常规核型差异不显著,在分类地位上非常接近。

Chromosome numbers, forms and karyotype of Mozambique tilapia （ Oreochromis mossambicus） and Zanzibar tilapia （Oreochromis hornorum） were analyzed and compared by using PHA-injection air drying method. Both of the two species of Tilapia had a diploid chromosome number of 44 with a large and long chromosome pairs. No metacentric chromosome pairs and heteromorphic chromosomes were found. The two fishes had similar karyotype and the conventional karyotype formula is 2n = 44, 6sm ＋ 24st ＋ 14t, NF = 50. It was difficult to distinguish the karyotype of the two tilapia species using the conventional technique. The result showed that the difference of karyotypes between the two tilapia species was not significant, indicating that they were quite close to each other in terms of classification status.