“高等”金缕梅类植物的分子系统发育和分化

利用叶绿体基因rbcL和matK，线粒体基因coxl的核苷酸序列比较研究“高等”金缕梅类植物的范畴、科间关系以及与其近缘类群的关系，并结合形态学性状分析，揭示该类群的系统发育和分化。探讨三个基因在被研究类群中的分子变异、演化速率和应用特点。为建立自然的被子植物分类系统提供重要证据；也将为认识可固氮植物类群的起源和亲缘关系提供线索。

Nucleotide sequences of five genes and one DNA region from three genomes were used to analyze the inter- and infra-familial relationships of Fagales. All 31 genera (excluding Ceuthostoma) were sampled representing eight families of the order. The parsimonious analyses of combined data set strongly supported the three major clades in the Fagales, i.e., Nothofagus, Fagaceae and core "higher" hamamelids. Nothofagus is sister to all the other Fagales, and Fagaceae is sister to the core "higher" hamamelids. Two main subclades were resolved in the core "higher" hamamelids by the combined analysis, one being Myricaceae (Rhoipteleaceae (Juglandaceae)), the other Casuarinaceae (Ticodendraceae (Betulaceae)). The latter subclade is strongly supported, while the former is moderately supported although the positions of Myricaceae are quite different in each single-gene trees. Fagaceae, Betulaceae and Juglandaceae form their own clade with 100% bootstrap support, respectively.