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公布，现在要求相当多的分类群的系统位置发生重大变化。本研究试图通过基于形态的证据来评估分子研究的结果，即胚胎学研究，特别是关于海星目的胚胎学研究。此外，鉴于各种植物群的分子数据信息越来越多，我还与大戟科和鳞毛蕨科(大戟科)、金龟子属(目前位置尚不确定)、塔赫塔亚科(冬虫科)进行了合作。与其他属不同的是，在巴豆亚科中，包括腺斜长石在内的6个属的内珠被薄，维管束稀少。与外群比较，与分子研究结果一致，这6个属很可能位于亚科的一条进化线上。鳞毛菌科传统上归于叶下珠亚科(大戟科)，具有纤维状的外被、内皮层和厚的内珠被，这些特征的结合表明鳞毛菌科不再属于叶下珠亚科，而是转移到了红木科和根霉科附近的位置。这一结论与来自分子证据的结论一致。其系统位置一直不确定，其种子直立，具匙形胚胎和非纤维状的外种皮，建议定位于核心盖的近基部。这一观点与分子证据所提出的观点相吻合。分子证据表明，海藻科(Asterales)的Argophyllum和Corokia具有适合于Asterales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.