中国凤仙花科植物叶表皮特征及其分类学意义(英文)

Leaf epidermal characters and their taxonomic significance in Balsaminaceae, China

关键词:  凤仙花科  凤仙花属  叶表皮  中国  分类学

Key words:  Balsaminaceae  Impatiens  leaf epidermis  China  taxonomy

摘要:

利用光学显微镜观察凤仙花科106份样本材料、36种代表植物的叶表皮微形态特征。结果表明:该科植物叶表皮微形态特征种内稳定,对于种间及属间关系的界定具有重要的分类学价值。上表皮细胞的形状及垂周壁的式样种间差异明显,各分类群间有明显的界限,是种间界定的重要依据,因此上表皮微形态特征具有重要的的分类学价值,基于上表皮的微形态特征将研究的36种代表植物划分为5个类型。下表皮的微形态特征虽更为多样,种间差异显著,可用于种间界定,但对于属下划分难以提供有价值的性状。该科植物叶表皮微形态特征与宏观形态特征的相关性较弱,与地理分布格局的相关性较强,关系更为密切。同一地理分布区域内的种类宏观形态特征虽然差别明显,但叶表皮微形态特征却表现出较强的一致性,这似乎也反映了叶表皮微形态这一性状受环境饰变的影响比较明显。综上所述,叶表皮微形态特征可为凤仙花科的系统发育,尤其是凤仙花属种间界定提供有价值的分类学佐证

Abstract:

The leaf epidermal characters of 106 field collections representing 36 species within the family Balsaminaceae,were investigated with light microscopy. Most epidermal characters were constant within species. These characters were valuable in clarifying species circumscriptions and relationships between the two Balsaminaceae genera,Impatiens and Hydrocera. Although abaxial epidermal characters were found to greatly vary between species,the adaxial epidermis presented much more valuable taxonomic characters. Based on the latter,the species were divided into five groups. Epidermal characters were closely correlated with geographical distribution rather than with gross morphology. Epidermal characters were found useful in demarcating species but had limited value in infrageneric subdivision. Epidermal characters appeared to be heavily modified by different environments.