DNA Phytogeography on Alpine Plants

本研究的目的是通过对高山植物的DNA序列变异进行历史分析，建立高山植物DNA地理学。本研究从日本列岛和北方环极区广泛采集了42种高山植物共210个样品。叶绿体DNA中trnL和trnF之间的基因间隔区主要用于此目的。作为测序的结果。（1）无种内DNA变异的物种，如红门兰（Orchis aristata）。(2)具有种内DNA变异但在地理上无意义的物种，例如Chamerion angustifolium、Vaccinium vitis-idaea和Solidago virga-aurea。(3)种内DNA变异具有显著地理意义的物种，如楔叶报春（Primula cunefolia）和马先蒿（Pedicularis chamissonis），在楔叶报春（Primula cunefolia）和马先蒿（Pedicularis chamissonis）中分别检测到6和11种DNA类型。在这两个物种中，植物可分为两个主要群体，北方和南方。分布于本州中央山区的南群在各山或山脉中分化为亚群，北群分化程度较低，分布范围较广。这种DNA核苷酸序列的地理变异对高山植物的历史分析无疑是有用的。

The present study aims to establish DNA phytogeography through the procedure to analyze historical aspects of the alpine plants on he basis of variation of nucleotide sequence of DNA.First of all, a new simple method to extract and amplify total DNA, because usually only small quantity of materials is available in the case of alpine plants. 210 samples of 42 alpine plants were widely collected not only from the Japan Archipelagoes but also from the circumpolar region of Northern Hemisphere. The intergenic spacer between trnL and trnF in chloroplast DNA was nainly used for this purpose. As the result of sequencing. three cases were recognized as followa :(1) Species without intraspecific DNA variation as exemplified by Orchis aristata.(2) Species with intraspecific DNA variation, but gegraphically meaningless, as exemplified by Chamerion angustifolium, Vaccinium vitis-idaea and Solidago virga-aurea.(3) Species with intraspecific DNA variation geographically significant, as exemplified by Primula cunefolia and Pedicularis chamissonis.In Primula cuneifolia and Pedicularis chamissonis, 6 and 11 DNA types were detected, respectively. In both species, the plants were divisible into two major groups, north and South. The south groups occupying the Central Moutain Regions of Honshu were found to have differentiated into subgroups in each mountain or mountain range, while the north group was less differentiated and distributed in rather wide area. Such geographical variations of DNA nucleotide sequence is certainly useful for historical anaysis of the alpine plants.