鲤鲫杂交回交鲫染色体核型及DNA含量的分析

摘要

The karyotypes were observed in metaphase chromo some specimens of back cross crucian carp F1 bred by female hybrids of common carp and crucian carp crossed with male crucian carp and injected with PHA and colchicine by short-term culture of kidney cells with air-drying technique.The DNA content sweredeter mined in the somaticcells of the backcross cru-cian carp F1 with body weight of 94. 2g using flowing cytometer and the DNA content of diploid control of red crucian carp as standard.The backcross cru-cian carp F1 had chromosome number of 3n= 147, with the karyotype form ula as 3n= 51m+ 24sm+ 27st+ 45t, and arm number of NF=222.The DNA relative contents of fourteen individuals of the backcross crucian carp F1,representing 70% of the twenty samples, were found to beashighas 1.5times of that in the diploidcontrol fish with.There were 6 triploid in dividualsaccounting for 30% of the total fish,showing the consistent with the results of the cellularkaryotypeanalysis,thatis,the backcross crucian carp F1 being the progeny with triploid cells.%将性成熟的鲤鲫杂交鱼一代（F1）的雌鱼与雄性红鲫鱼杂交，获得了回交鲫子代，分析了平均体质量94.2g的1龄回交鲫子一代的细胞染色体核型，测定了其DNA含量。肾细胞直接制片法表明：回交鲫子代染色体由147条组成，即3n=147，NF=222，其核型公式为：3n=51m+24sm+27st+45t。流式细胞记数法结果表明：在20尾鱼中有14尾回交鲫子代细胞的DNA含量是对照鱼（红鲫鱼）的1.5倍，占总鱼数的70%；6尾在2～3倍体之间，非常接近三倍体，占总鱼数的30%。本结果与其细胞染色体核型分析结果基本一致，说明该鱼是以三倍体为主的回交种。