【摘要】 采用水平淀粉凝胶电泳技术对分布于北京金山、檀柘寺、香山、樱桃沟的细距堇菜 (ViolatenuicornisW .Beck .)的遗传变异和群体分化进行了初步研究。对 8个酶系统 11个等位酶位点的检测表明 ,该种在上述地区的遗传变异水平明显高于多年生草本的平均值 ,多态位点百分率P =72 .7% ,等位基因平均数A =2 .4,平均期望杂合度He=0 .2 43 ;群体间的遗传分化略小于多年生草本的平均值 ,杂和性基因多样度的比率Fst=0 .196。检测了空间距离对遗传相似性的影响 ,发现二者无明显的相关性。研究了不同采样方法对遗传学估测的影响 ,表明对该物种的群体进行取样时每群体取 30株时有较充分的代表性 ,小于 2 0个个体的取样可能引起遗传多样性估测出现大的偏差 ,尤其是A和He2个指标易受样本大小的影响。更多还原

【Abstract】 Genetic diversity and population differentiation of Viola tenuicornis W. Beck. were studied in nine populations in Beijing using horizontal starch gel electrophoresis. Allozyme data for 11 loci of 8 enzymes indicated high level of genetic variability in this region with P =72.7%, A =2.4 and H e =0.243. In contrast, the population differentiation was lower than the average of other perennial herb with F st =0.196. It was found that distances among populations had little effect on population differentiation. A sample of 30 individuals could well represent a population, but less than 20 individuals per population might lead to significant bias in the estimation of genetic parameters, in particular the values of A and H e .更多还原