六属木兰科植物茎次生结构的比较研究

利用滑瞳切片技术和显微镜的手段观察了木兰科一年生茎的次生结构特征。通过对中国木兰科６属１２种植物一年生茎的次生结构进行描述和比较研究，为木兰科系统分类和林业资源树种的选择提供实验语气和积累研究资料。研究结果表明：木兰科植物茎的次生结构与其它原始木本双子叶植物相比表现出次生进化性状；次生木质部导管在横切面上的大小、形态和分布规律存在一定的差异，并有导管分布密集、管孔链和管孔团占优势向导管分布稀疏、单

COMPARATIVE ANATOMICAL STUDIES ON THE SECONDARY STRUCTURE OF ANNUAL STEM OF SIX GENERA IN MAGNOLIACEAE

The secondary structure of annual stem of 6 genera (12 species) from Magnoliaceae of China is described. The anatomical features of the secondary structure from annual stem may provide experimental evidence for systematics and the selection of the forestry resource plants. By means of slide sectioning technique, the secondary structure of annual stem is observed under light microscopy (LM). There are some differences between the species on the width,shape and distribution of the vessels in the secondary xylem. The occurrence of the phellogen and the activity of the vascular cambium is different between the species in the secondary structure. Althongh there is uncertain delimitation between the genera because of considerable overlap in characters, the features of the secondary structure have significance for the differentiation between species and the selection of the forestry resource plants in the Magnoliaceae of China.