河北3产地日本三角涡虫的染色体变异与核型多样性分析

Diversity of Chromosomes and Karyotypes of the Dugesia japonica from Hebei Province,China

利用空气干燥法,对采自河北省邯郸市漳河、朝阳湖和邢台市秦王湖3产地日本三角涡虫(Dugesiajaponica)染色体核型进行了研究,结果表明,日本三角涡虫漳河种群与秦王湖种群体细胞中染色体数目以16条为主(2n=2x=16=16m),分别占81.07%和68.47%,少数为24条(2n=3x=24=24m),分别占8.28%和11.71%,为二倍体和三倍体的混合倍体;日本三角涡虫朝阳湖种群体细胞中染色体数目以24条为主(2n=3x=24=24m),占64.60%,少数为16条(2n=2x=16=16m),占7.45%,为三倍体和二倍体的混合倍体。值得注意的是朝阳湖种群部分体细胞中染色体在结构上发生变异,使其核型呈现多型性。文中根据核型分析结果对上述3产地日本三角涡虫染色体及核型的多样性作了初步讨论。

The diversity of chromosomes and karyotypes of the freshwater planarians,Dugesia japonica,collected from Zhanghe River of Yuecheng Town and Chaoyang Lake in Handan City,Qinwang Lake in Xingtai City of Hebei Province were studied using the air-drying method.The results showed that most cells of D.japonica collected from both Zhanghe River and Qinwang Lake had the diploid chromosome number of 16 with a karyotype formula of 2n = 2x = 16 = 16m while a small proportion showed triploid of 24 chromosomes with a karyotype formula of 2n = 3x = 24 = 24m.The percentages of diploid cells were 81.07% and 68.47%,while those of triploid cells were 8.28% and 11.71% in the two local populations,respectively.D.japonica collected from Chaoyang Lake had both the triploid（2n = 3x = 24 = 24m） and the diploid（2n = 2x = 16 = 16m） cells and their percentages made up 64.60% and 7.45%,respectively.In addition,the karyotype of D.japonica from Chaoyang Lake showed polymorphism.Based on the above results,the diversity of chromosomes and karyotypes of the D.japonica from the three places was discussed.