重庆蚊母树属物种形态分化及种间亲缘关系的分析

QUANTITATIVE ANALYSIS OF MORPHOLOGICAL DIFFERENTIATION AND PHYLOGENETIC RELATIONSHIP AMONG THREE SPECIES OF DISTYLIUM IN CHONGQING

在测定重庆市仅有的蚊母树属3物种33个个体的32项形态指标的基础上,通过多种数量分析方法研究了物种形态分化及种间亲缘关系。结果表明:①各物种在个体水平上存在一定程度的形态分化,但分化程度不一;②蚊母树属植物营养器官形态分化较繁殖器官明显,说明繁殖器官受环境影响较小,性状较稳定;③3物种间鉴别性状明显,种间界定较为准确;④3物种间亲缘关系存在一定差异,在系统地位上中华蚊母树处于小叶蚊母树和杨梅叶蚊母树之间,与小叶蚊母树亲缘关系较近,而与杨梅叶蚊母树亲缘关系相对较远。

Thirty -two morphological indexes were recorded of 33 individuals from 3 species of Distylium in Chongqing, and several quantitative analysis approaches were used to study their morphologieal differentiation and phylogenetie relationship. Morphological differenliations were observed, to different extents, at the individual level in each species. The morphological differentialion of the vegetative organs appeared more significant than that of the reproductive organs, snggesting that the reproduetive organs are more stable and less influenced by the environment, The differentiation charaeteristies of the species were quite distinct and their classification proved to be correct.Phylogenetically.D.chinence,a transitional species,appeared between D.microcoides and D.buxifolium,and was closer to D.buxifolium that to D.microcoides.