摘要
报道了国产有鳞杜鹃57个种的叶背鳞片显微形态特征；比较了髯花杜鹃组与杜鹃组中22个亚组叶背鳞片的显微形态特征；依据鳞片脐的直径与边缘宽度比，边缘形态及其他特征，可分为五大类型：圆鳞片、大脐鳞片、小脐鳞片、放射状鳞片、红色厚鳞片，其中前三个还可分为10个小型。讨论了鳞片演化的趋势：（1）小圆鳞片是最原始的，小脐深裂鳞片是最进步的；（2）脐演化方向是大脐→小脐；（3）边缘演化方向是无边缘→有边缘、全线→浅波→浅裂→深裂；（4）边缘细胞末端的演化方向是平→圆→尖；（5）类群鳞片组合：单一类型→多样化。还讨论了一些类群叶背鳞片形态所处的演化阶段。
The micro-morphology of the scales on the lower leaf-surface of the 57 chinesespecies in the Subgen. Rhododendron has been observed at the present paper. The microcharacters of the scales were compared among the sections and subsections. The scaleswere divided into five groups and ten forms besed on the proportion of the Umbo-diameter to breadth of rim and different morphology of rim. The five groups are the rotundscale,the scale with big umbo,the scale with small umbo,the red thick scale,the radiatiform scale.The scales have been found with follow phylogentic trends:the small rotund scale isthe most primitive and parted scale with stnall umbo is the most davanced; the end ofrim-cell flat-round to tip;marginal entire→undulated→lobated to parted;fro single todiversity forms. Consequently the evolutionary stage of the scale in some groups was discussed.
出处
《西北植物学报》
CAS
CSCD
1997年第1期65-77,共13页
Acta Botanica Boreali-Occidentalia Sinica
关键词
有鳞杜鹃亚属
鳞片
形态
演化
Subgen, Rhodndendron,morphology of scale,evolution of scale
