The influence of chromosome polymorphisms of Ranunculus silerifolius (Ranunculaceae) to genetic diversity of populations

利用同工酶多态性分析，揭示了小野毛茛部分生殖分离的小野毛茛和松山毛茛细胞型之间的基因流动。混合准育群体中的小taro和Matsuyama细胞型可通过Mdh-3同工酶位点的不同等位基因进行关键区分，两种细胞型之间的杂种具有两种细胞型的两个等位基因。Mdh-3位点等位基因的分布模式表明，MIX内的细胞型之间不存在基因流动。同种异种群体MIX内两种细胞型间的基因流值（0.503）小于同种异种群体间的基因流值（2.550或1.700）。近育群体MIX内细胞型间的遗传距离大于相同细胞型的远距群体间的遗传距离。利用同工酶标记的变异对Nei’s遗传距离进行树图分析，结果表明小taro和Matsuyama细胞型分别形成了更多的集群。利用等位酶分析方法，对95个居群中具有特异染色体多态性（Karatsu型、Matsuyama型、Mugi型和otaru型）的兼性自交种毛毛兰（Ranunculus silerifolius）的遗传变异进行了研究。9个酶系的16个位点被解析。所有群体中有3个基因座为单态。平均26%的基因座是多态的；解析的16个位点共有49个等位基因，平均每个位点有1.29个等位基因。总体遗传变异水平与其他兼性自交物种一样低。居群间基因分化系数G_<ST>较高（0.579），可能反映了银叶小檗的近交现象。遗传距离和地理距离之间没有相关性可能是由于同样的影响。群体间遗传距离平均值较大（D=0.129），表明群体间分化程度高，基因流水平低（Nm=0.171），而细胞型间遗传距离平均值很小（D=0.008），这可能是由于细胞型发生后遗传多样化的良好期较短所致。少

Gene flow between partially reproductively isolated Otaru and Matsuyama cytotypes of Ranunculus silerifolius was revealed using allozyme polymorphisms. Otaru and Matsuyama cytotypes in the parapatric population MIX were distinguishable critically by the different alleles of the Mdh-3 allozyme locus, and the hybrids between both cytotypes shared both alleles of both cytotypes. The distribution pattern of the alleles of the Mdh-3 locus revealed that the gene flow did not occur between cytotypes within MIX. The value of gene flow between the two cytotypes within the parapatric population MIX (i.e.0.503) was smaller than those between allopatric populations of the same cytotype (i.e.2.550 or 1.700). The genetic distance between cytotypes within the parapatric population MIX was larger than those between the far distant populations of the same cytotypes. Dendrograms based on the Nei's genetic distance using the variations of allozyme markers showed that Otaru and Matsuyama cytotypes formed … More clusters separately.Genetic variations of the facultatively autogamous species Ranunculus silerifolius, which showed intra-specific chromosomal polymorphisms (Karatsu-, Matsuyama-, Mugi, and Otaru-cytotype), were investigated in 95 populations using allozymic analysis. Sixteen loci of nine enzyme systems were resolved. Three loci were monomorphic for all populations. On average, 26% of the loci were polymorphic ; the 16 loci resolved gave a total of 49 alleles with a mean number of 1.29 alleles per locus. Overall levels of genetic variation were low as with other facultatively autogamous species. The gene differentiation coefficient among populations, G_<ST> was high (0.579), which probably reflected the inbreeding in R.silerifolius. The absence of a correlation between genetic distance and geographical distance may have resulted from the same effect. The average of genetic distance between populations was large (D=0.129), indicating a high level of differentiation and low level of gene flow (Nm=0.171) among the populations, while that between cytotypes was very small (D=0.008), possibly due to the relatively short period of fine for genetic diversification since the occurrence of the cytotypes. Less