东北委陵菜属植物叶形态结构的研究及其分类学价值的探讨

首次采用了GMA半薄切片法对委陵菜属23种植物叶的形态结构进行了比较形态学研究。结果表明,东北委陵菜属植物的托叶类型多样,分为披针形、卵状披针形、卵圆形和叶状;叶柄横切面多为心形,此外还有马蹄形、近三角形和近圆形,维管束常为3个;叶表皮具腺毛和非腺毛;气孔均为无规则型,主要分布在下表皮;多数物种具韧皮纤维。本属木本植物金露梅及银露梅叶的许多特征(如毛状体类型,维管束数量及结构)与草本物种相似,故支持前人将二者放在委陵菜属。本研究可为委陵菜属的分类提供形态学依据,并为进一步深入研究中国委陵菜属以及蔷薇科的分类及系统学提供重要的基础资料。

Morphological study on the leaf structures of Potentilla in Northeastern China and its taxonomic value (Rosaceae)

The leaf structures of 23 species of Potentilla in Northeastern China were studied by the GMA method for the first time. The stipules varied in shape, including lanceolate, lanceolate-ovate, oval and lobate. The petioles in transverse section were usually heart-shaped, but could also be U-shaped, triangular or nearly round, and they usually had 3 vascular bundles. Glandular or nonglandular hairs were present on the epidermis of leaves. Stomata of the anomocytic type mainly occured on the lower epidermis. The phloem fibres were widely present in the taxa studied. The two woody species (Potentilla fruticosa and P. glabra) share many features with herbaceous plants, e.g. trichome type, number and structure of vascular bundles. Our study supports the placement of the two woody species in the genus Potentilla and provides morphological evidence for further taxonomic study of the genus and also provides morphological data for further study of Potentilla in China and in the Rosaceae.