单 位：
河南师范大学生命科学学院;周口师范学院生命科学系
摘 要：
[目的]分析河南省铜山湖淡水三角涡虫的核型,以期为其分类提供依据。[方法]采用空气干燥法制备染色体,对在河南省驻马店境内铜山湖产地首次采到的数十条淡水三角涡虫进行核型分析。[结果]研究发现,该产地三角涡虫中期分裂细胞中,染色体数目以25条为主(70.1%),还有少部分24条(14.2%),极少数16条(2.8%),是以三倍体2n=3x=24+1B为主,兼有很少的三倍体2n=3x=24和二倍体2n=2x=16的形式,8组中,最大组染色体的相对长度是最小组的2倍多,形态多为中着丝粒染色体。核型公式为2n=3x=24+1SB,表现出明显的二倍体和三倍体共存的多态性,总体属于2B。[结论]该分析结果为明确河南省淡水涡虫在我国物种上分布的地位提供基础资料。
译 名：
Karyotype Study on the Freshwater Planarian (Dugesia sp.) in Tongshan Lake of Henan Province
作 者：
MA Ke-shi et al(Department of Life Science,Zhoukou Normal University,Zhoukou,Henan 466001)
关键词：
Planarian(Dugesia sp.);Karyotype analysis;Henan Province;Tongshan Lake
摘 要：
[Objective] The purpose was to analyze the karyotype of freshwater planarian(Dugesia sp.)in Tongshan Lake of Henan Province so as to provide the basis for its classification.[Method] Dozens of freshwater planarian firstly selected from the producing area of Tongshan Lake in Zhumadian City of Henan Province were made for the karyotype analysis after using air-drying technique to prepare the chromosomes.[Result] It was found that in metakinesis cells of the planarian in this producing area,there were mainly 25 chromosomes,accounting for 70.1%;some 24 chromosomes,accounting for 14.2%;few 16 chromosomes,accounting for 2.8%.The freshwater planarian was mainly triploid of 2n=3x=24+1B and had both few shapes of triploid of 2n=3x=24 and diploid of 2n=2x=16.Among 8 groups of chromosomes,the relative chromosome length in the maximum group was more than 2 times of that in the minimum group and they had morphology of most middle-centromere chromosomes.It had the karyotype formula of 2n=3x=24+1SB,showing obvious multi-morphology for coexistence of triploid and diploid and it belonged to 2B in the general.[Conclusion] The karyotype of freshwater planarian in Tongshan Lake of Henan Province was composed of 24 chromosomes and 1 little B-chromosome.This study provided the foundational data for defining the status of the freshwater planarian of Henan Province in Chinese species distribution.
