基于叶表皮特征对25科40种药用植物显微鉴别的研究

目的 研究叶表皮形态特征对药用植物显微鉴定的意义。方法 利用光学显微镜和显微测绘器对25科40种药用植物的叶表皮形态进行观察、分类和研究，对特征参数进行相关性分析。结果 40种药用植物气孔轴式分为不规则类、不等类、横列类、平列类和四细胞类5种类型，47.5%的种类属于不规则类；表皮细胞形态分为不规则形、多边形和矩形，其垂周壁分为平直、平滑、V-波形和U-波形4种类型；50%的药用植物气孔指数在10～20，45%药用植物气孔密度为100～200个/mm²，70%药用植物叶片气孔器长宽比为1.00～1.50，为宽椭圆形，42%的药用植物气孔面积在401～600 μm²；77.5%药用植物叶片脉岛数在1.00～10.00个/mm²；88.2%药用植物栅表比在1～10。结论 单一叶表皮特征在药用植物显微鉴定中虽有物种差异性，但不具有专属性，多个叶表皮特征的结合或基于多个叶表皮特征建立的植纹是药用植物显微鉴定的有效途径。

Research of microscopic identification of 40 medicinal plants from 25 families based on characteristics of leaf epidermis

Objective To study the significance of leaf epidermis morphological characteristics on microscopic identification of medicinal plants. Methods The leaf epidermis of 40 medicinal plants species from 25 families were observed and studied by optical microscope and micro-mapper, and the characteristic parameters were analyzed by correlation analysis. Results The stomata shaft type of 40 medicinal plants species can be devided into five types: irregular type, unequal type, horizontal type, paracytic type and four-cell type, and 47.5% of species were irregular types. The morphology of epidermal cells can be divided into irregular, polygon and rectangle shape, while the anticlinal wall can be divided into straight, smooth, V-waveform and U-waveform. Stomatal index of 50% medicinal plants was between 10—20, stomatal density of 45% medicinal plants was 100—200 N/ mm². The length to wideth ratio of stomatal apparatus of 70% medicinal plants was between 1.00 and 1.50 with wide oval shape. Stomatal area of 42% medicinal plants was between 401—600 um²; The vein islet numbers of 77.5% medicinal plants were between 1.00 and 10.00 N/ mm², while the palisade ratio of 88.2% medicinal plants was between 1—10. Conclusion A single characteristics of leaf epidermis is species-specific withnot specificity in the microscopic identification of medicinal plants. The combination of multiple leaf epidermal features or the establishment of plant apparent pattern based on multiple leaf epidermal features is an effective way for the microscopic identification of medicinal plant.