杂交鳢(斑鳢♀×乌鳢♂)及其自交后代细胞核型初步分析

Karyotype Analysis of the Hybrid Snakehead (Channa maculata ♀×C.argus♂) and Its Inbred Progeny (F2)

对杂交鳢(斑鳢♀×乌鳢♂)(Channa maculata♀×C.argus♂)及其自交后代的细胞核型进行了初步分析。结果表明,杂交鳢染色体数目为2n=45,核型公式为3m+4sm+6st+32t,染色体臂数(NF)为52;杂交鳢自繁后代群体存在两种染色体核型,一是染色体数目为45,核型公式为3m+4sm+6st+32t,NF=52,另一种为染色体数目44,核型公式为2m+4sm+6st+32t,NF=50。经对比分析,在F2群体中,染色体数目为45的核型公式与杂交鳢相似,而染色体数目为44的与杂交鳢相比少了一条中部着丝点的染色体。推测杂交鳢减数分裂可能会产生染色体数目分别为23条和22条的两种配子。

The diploid chromosome number and karyotype of Hybrid Snakehead （ Channa maculata ♀× C. argus ♂ ） and its inbreeding population （F2） were studied by somatic cells in vivo culture. The results indicated that the diploid chromosome number of hybrid snakehead was 2n = 45, karyotype formula was 3m ＋ 4sin ＋ 6st ＋ 32t,and arm number （NF） was 52. The inbreeding population （F2） had two kinds of karyotype, a sort of diploid chromosome number 2n = 45, and karyotype formula 3m ＋ 4sin ＋ 6st ＋ 32t, NF = 52 ; and the other diploid chromosome number 2n = 44, and karyotype formula 2m ＋ 4sin ＋ 6st ＋ 32t, NF = 50. The comparative analysis showed that the karyotype formula of F2 （2n = 45 ） was consistent with that of hybrid snakehead, however there was a metacentric chromosome missed in chromosome of some F2 individuals （2n = 44 ） compared to hybrid snakehead. Therefore,it can be speculated that hybrid snakehead may produce two kinds of generative cells with 23 and 22 chromosomes, respectively.