伞形科山芹属叶表皮微形态特征研究

摘要

利用扫描电镜技术对伞形科山芹属(Ostericum Hoffm.)9种2变种(21居群)植物叶表皮微形态特征进行了观察分析.结果显示:山芹属植物叶片上表皮表面均较平滑,细胞轮廓清晰或不清晰,若细胞轮廓可见则为多边形与不规则形;初级蜡质纹饰为较密集的粗(细)条状,部分种类具有单层或双层脊状二级纹饰或有颗粒状或分枝状附属结构;下表皮亦有类似蜡质条状纹饰,均匀分布或集中在气孔周围或凹凸部位,气孔器形状多为椭圆形(偶见梭形),内外拱盖表面粗糙或光滑.上述研究表明,山芹属叶片微形态特征具有良好的种内稳定性和种间多样性,尤其是初级纹饰的宽度及排列密度、二级纹饰以及气孔器形状等特征,可为山芹属植物种间和种下的近缘类群亲缘关系与分类修订提供形态学依据.%The morphological characters of leaf epidermis of 9 species and 2 varieties (21populations) of Ostericum Hoffm.were investigated by scanning electron microscopy (SEM).The leaf epidermal surfaces of Ostericum are smooth normally,and epidermal cell contours are invisible or distinct with polygonal or irregular shape or invisible.Most primary waxy ornamentations are dense stripes (thick),and some species have single or double ridged secondary or namentations,or branched or granular attachment structures;the abaxial epidermals also have stripes waxy ornamentations,which are evenly distributed for most species,while for a few species the waxy ornamentations only occur around the stoma or convex/concave parts,and stomatal shape is ellipse or fusiform with rough or smooth surface.These results show that the morphological characteristics have certain intraspecific stability and interspecies diversity,especially the width and the density of the primary ornamentation,the secondary ornamentation and the shape of the stomatal apparatus,which are probably have a potential significantce for the genetic relationship and taxonomic revision of the genus and its members.