Studies On The Karyotypes Of The Freshwater Planarians In China (XI)

Karyotype analysis was carried out on freshwater planarian (Dugesia sp) populations from 15 sampling sites of China, Sichuan mountain range, Shanxi Qinling Mountains and Henan Funiu Mountains. Chromosomic plates were obtained by air-drying method. The results showed that the karyotype of freshwater planarian collected from Yuhuangmiao Zhouzhi County of Shaanxi Province village is triploid aneuploid,few of them is variant karyotypes,a formula being 2n=3x=25=14m+7sm +3st+1SB , A small number of triploid karyotype formula is 2n = 3x = 24 = 24m;the karyotype of freshwater planarian collected from Dayukou of Xi'an is triploid aneuploid,planarians as an integer multiple of triploid karyotype formula is: 2n = 3x = 24 = 24m; the karyotype of freshwater planarian collected from Liu lin cun Village of Xi'an planarians are triploid karyotype formula were 2n = 3x = 24 = 21m +3sm;wang jia River of zhou zhi County are tetraploid planarians, the karyotype formula is 2n = 4x = 32 = 28m +4 sm; yang zi gou are mainly triploid planarians,the karyotype formula was 2n = 3x = 24 = 24m, a small number of diploid ,the karyotype formula is 2n = 2x = 16 = 16m; Meng jia cun village in planarians mainly triploid karyotype formula is 2n = 3x = 24 = 20m +4 sm, a small number of diploid karyotype, the karyotype formula is 2n = 2x = 16 = 16m. xiao yukou tetraploid planarians to the main karyotype formula is 2n = 4x = 32 = 32m, of which the chromosome arms larger the ratio of the sixth group; Cuihuashan of Xi'an parasites of freshwater are mainly triploid planarians, have variant karyotypes, the karyotype formula is 2n = 3x = 24 = 21m +3 sm, karyotype of a small number is 2n = 3x = 24 = 20m +4 sm, Pao Mashan of Kangding, Sichuan mountain range region are mainly triploid planarians aneuploidy , karyotype is unique, the karyotype formula is 2n = 3x +2 = 24 +2 = 19m +3 st +4 sm; the karyotype of freshwater planarian collected from batang,daocheng and banghe village of sichuan Province are tetraplont aneuploid,a formula being 2n=3x=32,and the karyotype formula of freshwater which collected from daocheng being 2n=3x=32=29m+3st;the primarily karyotype of freshwater planarian collected from yala river is triploid aneuploid,a formula being2n=3x=24+1SB;the primarily karyotype of freshwater planarian collected from yuhuang temple of zhouzhi county in shanxi Province is diplont aneuploid,a formula being2n=2x=40=26m+14sm;the primarily karyotype of freshwater planarian collected from guangtoushan of zhouzhi county in shanxi Province is diplont aneuploid,a formula being2n=2x=38=26m+12sm.According to the above results, making an analysis of the karyotype asymmetry and evolution index of freshwater planarians collected from 15 localities, the results showed that the freshwater planarian collected from Paomashan town, Yuhuangmiao village and Daocheng County had the most asymmetric karyotype, and had the highest index of evolution, so they had the highest degree of evolution.