【摘要】 用采自34个现场螺点的钉螺进行水平淀粉凝胶电泳,并进行13种酶系统染色.结果17个等位基因中,7个为多态基因位点.种群间遗传距离的变化范围0.03—0.27.UPGMA、Fitch-Mar-golish最小方差法、最大相似性聚类分析图显示,聚类的组别与形态学或/和地理分布相一致.各分析指标提示,肋壳钉螺种群显著地不同于光亮钉螺种群,两组间的遗传距离为0.15.更多还原

【Abstract】 In order to understand the genetic variation of Oncomelania snails in the mainland of China, the field snails from 34 localities were collected and were investigated by the way of allele enzyme electrophoresis. Results demonstrated that out of 17 loci examined,7 polymorphic loci were presented,among which,the major loci of Est-4. Got,Mdh-2,Idh-2 and Ap accounted for the main variations within and among 34 populations. Genetic distance (Nei’s 1978) a-mong the populations varied from 0. 03 to 0. 27. The dendrogram based on UPGMA,Fitch-Margoliash and least-squares,and maximum likelihood cluster analysis,showed that the cluster groups corresponded to both morphology and geographic distribution of the snails. The principal component analysis of allele frequencies plotted by factor 1 with factor 2 in the analysis of genetic variation among populations,demonstrated that the populations of snails with smooth shells differed significantly from the populations of snails with ribbed shells and the gentic distance between the two groups was 0. 15 (Nei’s 1978).更多还原