中国溲疏属叶表附属物的显微形态及其分类意义

The micromorphology of foliar indument of the genus Deutzia in China and its taxonomic implication

在光镜下对国产绣球花科溲疏属（ＤｅｕｔｚｉａＴｈｕｎｂ．）３７种１５变种叶表附属物进行了观察、测量，对个别种进行了扫描电镜观察．溲疏属叶表面除个别种无毛外几乎均被星状毛（Ｓｔｅｌａｔｅｈａｉｒｓ）．根据星状毛在叶表的情况可分为３种：贴伏星状毛、具中央辐射线的星状毛及具柄的星状毛．具柄的星状毛仅在极少数种内出现．综合叶表星状毛的光镜观察结果，讨论了叶表附属物在该属中的系统演化趋势及在某些系、种间关系上的分类意义．对一些疑难分类群，如灌丛溲疏（Ｄ．ｒｅｈｄｅｒｉａｎａＳｃｈｎｅｉｄ．）的界定以及对在伞花亚组（Ｓｕｂｓｅｃｔ．ＣｙｍｏｓａｅＲｅｎｄ．）中建立多辐系（Ｓｅｒ．ＭｕｌｔｉｒａｄｉａｔａｅＰ．Ｈｅ）和寡辐系（Ｓｅｒ．ＰａｕｃｉｒａｄｉａｔａｅＰ．

Foliar indument of 37 species plus 15 variaties of the genus Deutzia of Hydrangeaceae in China were examined by the light microscope (LM) and a few species were further studied under scanning electron microscope (SEM).Except a few species are with glabrate leaves,most species in this genus have leaves covered with stellate hairs on both sides.The stellate hairs can be divided into three types,i.e.,appressed stellate hairs,stellate hairs with central rays and stellate hairs with stalks.The third type occurs on leaves of only a few species.Based on the results of the observation on foliar indument under LW,we further discussed the evolutionary trends of foliar indument in the genus and the taxonomic significance in some series,and species groups.Evidence on the foliar indument is of significance for the treatment of some doubtful taxa,such as D.rehderiana Schneid.,and for the establishment of two series named Ser. Multiradiatae P.He and Ser. Pauciradiatae P.He in Subsect. Cymosae Rend..