乌冈栎天然居群叶表型变异

Phenotypic Variation of Quercus phillyraeoides in Natural Populations

运用方差分析、聚类分析和主成分分析等数量分类学方法,对分布于9个地区的乌冈栎叶表型10个性状变异进行了研究。结果表明:①从10个叶表型性状的实测数值显示,不同地区乌冈栎表型性状存在较大差异,但叶长宽尺寸呈正相关关系(y=9.670 2+0.226x,R2=0.572,P<0.001);②叶型各指数的单因素方差分析和变异系数的结果,均支持表型存在分化的结论,但分化程度大小不一;③表型分化系数表明,总变异中居群间变异占30%左右,而居群内变异占了70%,这说明乌冈栎叶表型变异其主要动力来源于居群内;④聚类分析和主成分分析的结果均显示,利川分布的乌冈栎居群与其他地区有较大区别,在类群的划分中独立于其他居群之外;⑤乌冈栎叶表型与环境的相关性差异不显著,但水分对叶型的影响要大于温度。最后,在数量分类学的基础上对利川栎进行了讨论,将其调整为乌冈栎的变种是合理的。

The quantitative methods,such as variance analysis,regression analysis and principal component analysis,were used to discuss the variation of 10 phenotypic traits of Quercus phillyraeoides in 9 populations.The results showed： ①10 leaf phenotypic value indicated that significant difference existed among the populations,but the size of length and breadth was positively correlated（y=9.670 2＋0.226x,R2=0.572,P0.001）;②the phenotypic differentiation performed differently among the populations,which was supported by the coefficient of variation and one-way analysis of variance,but the differentiation degrees were not uniform;③the coefficient of phenotypic variation revealed that intrapopulation variation accounted for 70% and extrapopulaton variation about 30% respectively,which showed that intrapopulation variation mainly contributed to morphologic variation;④regression analysis and principal component analysis indicated that the individuals of Q.phillyraeoides in Lichuan were different from those of other populations,and the former was separated;⑤there was no significant correlation difference between leaf morphology of Q.phillyraeoides and environmental factors,but the effect of water on the leaf shape was more important than that of temperature.Based on the measurement of numerical taxonomy,it is concluded that Quercus lichuanensis should be the variety of Q.phillyraeoides,which is named Q.phillyraeoides var.lichuanensis（Cheng） C.P.Xie et Y.M.Fang.