运用形态特征和分支、表征方法探讨广义花楸属( Sorbus L. ) 属下分类关系

 选取了广义花楸属(Sorbus L. ) 属下6个亚属的34种植物作为研究对象, 并以Pyrus, Crataegus, Photinia, Malus和Cotoneaster作为外类群, 对其典型的30个形态性状数据进行编码, 采用分支分析和表征分析的方法研究花楸属属下类群的分类关系。结果表明, 广义花楸属是一个非单系类群, 外类群完全镶嵌于其中; 属下的6个亚属各自不能形成单系, 只有花楸亚属( Subgenus Sorbus) 形成不严格的单系。作者初步认为, 花楸属应该仅包含复叶类群( Subgenus Sorbus) , 或者还会有Subgenus Cormus。由于其余的4个亚属尚不能形成规则的单系或聚类, 故进一步的研究宜采用分类群的更多性状或运用分子系统学的途径。

A Cladistic and Phenetic Analysis of the Infrageneric Relationships of Sorbus s.l.(Maloideae,Rosaceae)Based on the Morphological Characters

Based on 30 morphological characters,34 species representing six subgenera from Sorbus s.l.,and five outgroups,Pyrus,Crataegus,Photinia,Malus and Cotoneaster,were sampled to investigate the infrageneric relationships by means of the cladistic and phenetic analysis.The results indicate that Sorbus s.l.was entirely not a monophyly,and outgroups were nested in Sorbus s.l.Six subgenera in Sorbus s.l.could also not formed monophyly respectively,only subgenus Sorbus with pinnate leaves seems constituted a cluster.Therefore,the infrageneric relationships should be studied by adding more morphological characters of taxa or by a molecular systematic approach.