二倍体泥鳅×四倍体泥鳅F1不同发育阶段染色体核型分析

Chromosome karyotype analysis of different developmental stages F_1 by diploid loach×tetraploid loach

以中国长江流域天然四倍体泥鳅为父本,大连农贸市场二倍体泥鳅为母本,通过倍间杂交获得杂交三倍体泥鳅,对早期胚胎、6月龄及12月龄染色体核型进行初步分析。结果表明,早期胚胎整3倍体染色体数目为3n=75,核型为16M+7SM+52T,NF=98,亚三倍体染色体数目为3n=73,核型为15M+6SM+52T,NF=94,超三倍体染色体数目为3n=76,核型为16M+6SM+54T,NF=98;6月龄整三倍体染色体数目为3n=75,核型为15M+6SM+54T,NF=96,亚三倍体染色体数目为3n=72,核型为15M+6SM+51T,NF=93,超三倍体染色体数目为3n=77,核型为15M+6SM+56T,NF=98;12月龄整三倍体染色体数目为3n=75,核型为12M+8SM+55T,NF=95;亚三倍体染色体数目为3n=71,核型为16M+6SM+49T,NF=93,超三倍体染色体数目为3n=76,核型为18M+8SM+50T,NF=102。结果表明,二倍体泥鳅×四倍体泥鳅杂交后代是含有三套染色体组的三倍体,不同发育阶段整三倍体染色体数目相同,均为3n=75,但染色体核型表现多态性。非整倍体(超三倍和亚三倍)中增加和缺少的染色体数目及类型无规律可循。

Chromosomal karyotype of early embryos,six month age sample and twelve month age sample were analyzed by different ploidy from the cross of hybridtriploid loach in the Yangtze River China natural tetraploid loach as male parent, Dalian farmers market diploid loach as female parent. The results showed that karyotype and fundamental number were determined to be 3n=75, 16M＋7SM＋52T, NF=98 in triploid, 3n=73, 15M＋6SM＋52T, NF=94 in sub-triploid, 3n=76,16M＋6SM＋54T, NF=98 in super tdploid, 3n= 75, 15M＋6SM＋54T, NF=96 in triploid of six month age, 3n=72, 15M＋6SM＋51T, NF=93 in sub-triploid of six month, 3n=77, 15M＋6SM＋56T, NF=98 in super triploid of six month age, 3n=75,12M＋8SM＋55T, NF=95 in triploid of twelve month age, 3n=71, 16M＋6SM＋49T, NF=93 in sub-triploid of twelve month age, 3n=76, 18M＋8SM＋50T, NF=102 in super tdploid of twelve month age. The results showed that hybrids （diploid Ioachxtetraploid loach） were triploid with the same chromosome number 3n=75 （three sets of chromosomes） in different developmental stages, but polymorphism on karyotype. The number and the type of chromosome （increase and deletion） are no rules in aneuploid （hypertriploid and hypotriploid）.