中国溲疏属种子形态及其分类学意义

Seed morphology and its taxonomic significance of Deutzia Thunb.In China

在光学显微镜下观察了中国溲疏属32种13变种的种子形态,探讨了种子形态的分类学意义,结果表明,1该属植物的种子可分为两大类:①大型种子,较原始,包括小花溲疏组和溲疏组下溲疏亚组;②小型种子,较进化,包括溲疏组下大花溲疏亚组、狭萼溲疏亚组和聚伞花序溲疏亚组;2拥有相似的种子特征,支持溲疏属的单源性假设;3在种子形态上系间或种间差别不明显,而组间或亚组间却存在一定的规律性变化;4种子形态支持长江溲疏隶属于溲疏亚组,恢复A.Rehder建立的大花溲疏亚组,以及将城口溲疏独立成种而非四川溲疏的变种的处理.

The seeds of 31 species and 13 varieties of Deutzia in China were examined under light microscope,and the taxonomic significance of seed morphology was discussed.The results are as follows: 1 The seeds can be divided into two types: the bigger type and smaller type.The first type is more primitive,including seeds in Sect. Mesodeutzia Schneid.and Subsect. Deutzia of Sect. Deutzia .The second type is more derived,including seeds in Subsect. Grandiflorae Rehd.,Subsect. Stenosepalae Schneid.and Subsect. Cymosae Rehd.of Sect. Deutzia . 2 All studied species of Deutzia share rather similar seed characters,which supports that it is a monophyletic genus. 3 The difference on seed morphology among series or species is not very distinct.However,there is regular change on seed morphology among sections or subsections. 4 Seed morphology supports the following treatments: ① D.schneideriana Rehd.belongs to Subsect Deutzia; ② The rank of Subsect Grandiflorae Rehd.should be restored; ③ D.fargesii should stand alone as a species rather than a variety of D.setchuenensis.