0769114881esia sp)的染色体研究(Ⅰ).pdf

　遗 传 学 报 　Acta Genetica Sinica , November 2003 , 30 ( 11) : 1045～1050 ISSN 0379 - 4172 Chromosome Studies of the Freshwater Planarians( Dugesia sp) from China( Ⅰ) 1 ,2 2 2 , ① 2 2 MA JinYou , L JiuQuan , CHEN GuangWen , XU CunShuan , LIU DeZeng ( 1Department of Animal Science , Henan VocationTechnical Teachers College , Xinxiang 　453003 , China ; 2 College of Life Science , Henan Normal University , Xinxiang 　453002 , China) Abstract : The karyotypes of freshwater planarians were studied through the chromosome metaphases prepared from regenerative cells using an airdrying technique. The results showed that Dugesia sp collected from Yuquan in Henan Province and Longjing in Zhejiang Province both had a diploid number of 16 with a chromosome formula of 2n = 2x = 16 = 16m. Dugesia sp collected from Bulaoquan in Henan Province possessed a triploid number of 24 with a chromosome formula of 2n = 3x = 24 = 24m. Chromosomes of planarians collected from these localities were similar in size and morphology. Dugesia sp collected from Yingtaogou ,Beijing City ,possessed a triploid number of 24 with a chromosome formula of 2n = 3x = 24 = 22m + 2sm ,and there was one chromosome belonging to submetacentric chromosomes in the second and the fourth chromosome ,respectively. According to the results mentioned above ,the karyotypes of Dugesia sp include diploid and triploid ,their chromosome numbers were n = x = 8 ,2n = 2x = 16 ,and 2n = 3x = 24 ,respectively. Also ,the comparison and analysis of these karyotypes from a taxonomical point of vi