分子系統解析の成果を形態形質(生殖構造の形質)で評価する―キキョウ目(キク目)を例にして

各种植物类群的分子系统发育研究数据迅速发表，现在需要对相当多分类群的系统位置进行剧烈的改变。该研究项目试图通过基于形态学的证据来评估分子研究的结果，即胚胎学研究，特别是关于Asterales的研究。此外，鉴于各种植物类群的分子数据信息不断增加，我还对大戟科的Crotonoideae和Drypeteae、Setchellanthus（最近才确定位置）、Takhtajania （Winteraceae）进行了研究。本课题的研究成果总结如下：在Crotonoideae中，与其他属相比，包括Adenocline在内的6个属具有缺乏维管束的薄内被。与外群相比，与分子研究结果一致，这6个属可能处于亚科进化谱系的基础位置。传统上被归入千层亚科（大戟科）的杉木科具有纤维状的外被层、内皮层和厚的内被层，这些特征的结合表明杉木科不再被归入千层亚科，而是被转移到接近红木科和根茎科的位置。这一结论与分子证据的结论一致。Setchellanthus的系统位置一直不确定，发现其种子直，胚为匙形，外胚芽为非纤维状外胚芽，可能位于近基部至核心Capparales。这个位置与分子证据表明的位置相吻合。石竹科石竹属和石竹属石竹属具有适合石竹属的胚胎学特征。

Data of molecular phylogenetic studies are rapidly published for various plant groups, and are now requiring drastic changes of the systematic position of quite a few taxa. This research project has attempted to evaluate results of molecular studies by means of morphology-based evidence, I.e., embryological study particularly with respect to Asterales. Besides, in view of increasing information of molecular data for various plant groups, I have also worked with Crotonoideae and Drypeteae (Euphorbiaceae), Setchellanthus (position uncertain till recent time), Takhtajania (Winteraceae).Results of this research project are summarized as follows. In Crotonoideae, in contrast to other genera, six genera including Adenocline have a thin inner integument destitute of vascular bundles. Compared to outgroup, in agreement with results of molecular studies, the six genera are likely to be positioned basal in an evolutionary line of the subfamily. Drypeteae, traditionally placed in Phyllanthoideae (Euphorbiaceae), have a fibrous exotegmen, an endothelium, and a thick inner integument, and a combination of these features indicates that Drypeteae are no longer placed in Phyllanthoideae and rather he transferred to a position near Erythroxylaceae and Rhizophoraceae. This conclusion agrees with that from molecular evidence. Setchellanthus, whose systematic position had been uncertain, was found to have straight seeds with a spathulate embryo and a non-fibrous exotegmen and suggested to be positioned near-basal to the core Capparales. The position fits in with that suggested by molecular evidence. Argophyllum and Corokia of Argophyllaceae (Asterales) have embryological features suitable to Asterales as suggested by molecular evidence.