中国栎属(壳斗科)基于叶表皮及叶结构特征的分支分析

A Cladistic Analysis of Quercus (Fagaceae)in China Based on Leaf Epidermis and Architecture

以三棱栎为外类群 ,基于叶表皮及叶结构特征对中国栎属进行初步的分支分析。结果显示了栎属内稳定的“支”结构及其种间关系。栎亚属可划分为 5个组 ,分别为巴东栎组、高山栎组、子栎组、麻栎组和槲栎组。子栎组是栎亚属常绿栎类与落叶栎类之间的过渡类群 ;高山栎组应为栎亚属常绿栎类中的特化类群 ,而非最原始类群。 5个组中 ,仅巴东栎组不是单系类群 ,而是一个多系类群。青冈亚属较栎亚属早分支 ,可划分为 3大类 :无毛类、简单被毛类和复杂被毛类 ;无毛类最原始 ,复杂被毛类与栎亚属关系最近。因此 ,叶表皮及叶结构特征对解决栎亚属组间亲缘关系有重要的分类学意义。

A cladistic analysis of the genus Quercus L.in China was performed based on leaf epidermis and architecture using Trigonobalanus doichangensis (A.Camus)Farman as an outgroup. Some stable relationships among subgenera and species were indicated by the cladistic analysis.Subgen.Quercus were divided into five sections, namely Sect.Engleriana,Sect.Brachylepides,Sect.Echinolepides,Sect.Aegilops, and Sect. Quercus. Sect.Echinolepides was an intermediate group between evergreen and deciduous oaks of Subgen.Quercus. Sect.Brachylepides was a specialized group. Only Sect.Engleriana was polyphyletic,not monophyletic among five sections. Subgen.Cyclobalanopsis diverged earlier than Subgen.Quercus,treated as three groups,namely glabrate group,simple-haired group and complicated-haired group. The complicated-haired group has the closest relationship with Subgen.Quercus.Leaf epidermis and architecture were significant in taxonomy for Subgen.Quercus.