新疆委陵菜属不同花柱组植物叶表皮微形态结构的研究

利用光学显微镜和扫描电子显微镜,观察了新疆委陵菜属5组不同花柱组10种4变种植物叶表皮的微形态特征,测量统计叶表皮毛的类型、表皮细胞的形状及大小、气孔器的分布及类型、气孔的形状、大小、密度及指数、气孔外拱盖形态及其纹饰等指标。结果显示:新疆委陵菜属10种4变种植物叶的下表皮均有气孔器的分布,形状为长椭圆形、椭圆形、宽椭圆形和近圆形;气孔器的类型多为无规则四细胞型、无规则型、围绕型和辐射型;表皮毛的类型为针状毛、带状柔毛和腺毛;表皮细胞的形状分为不规则形和多边形2种类型。研究表明,新疆委陵菜属植物表皮毛特征、叶片表皮细胞的形状、垂周壁式样、气孔器的形状类型、气孔密度指数及外围蜡质纹饰等存在差异,对属以下等级的划分有重要价值,可作为物种分类及鉴别的依据,同时也为本属一些分类群间的系统关系的探讨提供佐证。

Leaf Epidermal Micro-morphology Structures of Different Groups of Potentilla L.from Xinjiang

The leaf epidermal cell micromorphology of 10 species and 4 variations from five different groups of Potentilla L.of Xinjiang were investigated under light microscope (LM) and scanning electron microscope (SEM).The type of epidermal hairs,the size and shape of epidermal cells,the distribution and type of stomatal apparatus were studied.The stomatal size,stomatal density,and stomatal index were measured and counted.The shape and the ornamentation of outer stomatal rim were described.The results showed that there were stomatal apparatus on lower epidermal of all the 10 studied species and 4 variations.The shapes of stomatal apparatus are oblong oval,oval,broadly oval and suborbicular.The stomatal apparatus of most species are short paracytic four-cell type,irregular four-cell type,irregular type,around type and radial type.The trichomes are needle-like hairs or ribbon pubescent hairs.The epidermal cells are polygonal to irregular.The characters of stomatal apparatus,stomatal index,wax ornamentation and trichomes are all obviously different among different species in genus Potentilla L.The leaf epidermal morphological characters could provide evidence to identify species,classify subgenus and study the systematic relationships of taxons of Potentilla L.