Genetic divergence of intraspecific aneuploids in Carex conica.

对日本146个种群1556株圆锥苔属植物的染色体数目进行了测定。7个非整倍体，2n=32、33、34、35、36、37和38。以二倍体偶数染色体2n=32、34和36最为常见，且地理分布不同。通过9个酶系的电泳分析，研究了圆锥体4个非整倍体（2n=32、34、36和38）的遗传差异。采用水平聚丙烯酰胺凝胶电泳。对9个酶系统进行了10个可解释位点的评分。计算每个群体的等位酶频率。根据等位基因频率计算了17个群体间的遗传距离（Nei, 1972）。利用NJ法和Fitch-Margoliash法对遗传距离进行聚类，确定居群间的关系。识别出4个集群：(1)濑户内海沿海地区2n=32,(2)日本本州东部地区2n=34,(3)中国、四国和九州山区2n=36,(4)栃木县2n=38。2n=36的20个居群（0.113）和2n=34的24个居群（0.099）种内遗传距离较高，而2n=32的14个居群（0.039）和2n=38的2个居群（0.030）种内遗传距离较低。这些结果表明2n=32和2n=38植物在最近的物种形成中已经分化。

Chromosome numbers were determined for 1556 plants of Carex conica from 146 populations in Japan. Seven aneuploids, 2n=32,33,34,35,36,37 and 38, were found. Plants with even diploid chromosome numbers 2n=32,34 and 36 were the most common and had different geographical distributions. Genetic divergence was examined in the four aneuploids of C.conica (2n=32,34,36 and 38) by electrophoretic analysis of nine enzyme systems. Horizontal polyacrylamide gel was used for electrophoresis. Ten interpretable loci were scored for nine enzyme systems. Allozyme frequencies were calculated for each population. Genetic distances (Nei, 1972) among 17 populations were calculated from the allele frequencies. Relationships among populations were determined by clustering the genetic distances using NJ and Fitch-Margoliash methods. Four clusters were recognized : (1) 2n=32 from coastal areas of Seto Inland Sea, (2) 2n=34 from eastern Honshu of Japan, (3) 2n=36 from the mountainous areas of Chugoku, Shikoku and Kyushu, (4) 2n=38 from Tochigi Prefecture. Intraspecific genetic distances among 20 populations of 2n=36 (0.113) and 24 of 2n=34 (0.099) were relatively high, but 14 of 2n=32 (0.039) and two of 2n=38 (0.030) were low. These results suggested that 2n=32 and 2n=38 plants have been differentiated in recent speciation.