色木槭与元宝槭表型性状分类学研究

A taxonomic study on phenotypic traits of Acer mono and Acer truncatum

[目的]探寻色木槭与元宝槭的分类性状,以期为两种槭树的分类鉴定提供科学依据。[方法]以辽宁省色木槭与元宝槭8个天然种源共47个样本为研究对象,采用变异分析、相关分析、主成分分析、聚类分析等方法,对其叶片和果实的25个表型性状进行研究。[结果]色木槭与元宝槭表型性状的平均变异系数为15.22%,平均Shannon-Wiener多样性指数为1.98,各种源变异水平较高,表型多样性丰富,其中叶片性状的变异程度大于果实性状。各样本叶片和果实性状受经度和海拔的影响显著,辽东地区以色木槭分布为主,辽西地区以元宝槭分布为主。通过R型聚类分析筛选出23个主要性状进行主成分分析,其中第一主成分代表叶裂宽度性状,第二主成分代表叶裂长度和果实长度性状,主成分向量散点图可将各样本按地理位置的东西分布分类,结合逐步回归分析,叶片长等9个性状可作为评价两种槭树的主要性状。Q型聚类分析将47个样本分为3类,果长、张开角和翅果比在组间差异最大,其分类结果与相关分析和主成分分析结果一致。[结论]叶片长、叶片宽、左下裂片长、叶基部左侧宽度、翅长、果长、着生痕长、果厚、张开角和翅果比可作为区分色木槭与元宝槭的分类依据,其中果长、张开角、翅果比是两种槭树表型的核心分类性状,具有果长≤10 mm、张开角≥114°、翅果比≥1.6的形态特征可认定为色木槭,果长≥14 mm、张开角≤84°、翅果比≤0.9的形态特征可认定为元宝槭。本研究结果可为槭属植物表型性状的种间鉴定和分类体系构建提供标准和依据。

【Objective】In order to provide scientific basis for classification and identification of Acer mono and Acer truncatum,we explored the classification traits of the two Acer species.【Method】47 A.mono and A.truncatum samples from 8 natural provenances in Liaoning were selected as the research objects,and 25 phenotypic traits of leaves and fruits were studied by methods of variation analysis,correlation analysis,principal component analysis and cluster analysis.【Result】The average variation coefficient for phenotypic traits of A.mono and A.truncatum was 15.22%,and the average Shannon-Wiener diversity index was 1.98.The variation level of various provenances was relatively abundant,the phenotypic diversity was rich,and the variation degree of leaf traits was greater than that of fruit traits.The leaf and fruit traits of each sample were significantly affected by longitude and altitude.The distribution of A.mono was mainly in the eastern Liaodong region,while A.truncatum was mainly distributed in the western Liaoning region.Through R-type cluster analysis,23 main traits were screened for principal component analysis.The PC1 represented the leaf crack width trait,and the PC2 represented the leaf crack length and fruit length traits.The principal component vector scatter plot can classify each sample according to the geographical distribution.Combined with stepwise regression analysis,9 traits such as leaf length can be used as the main traits to evaluate the two Acer species.Q-type cluster analysis divided 47 samples into three groups.Fruit length,open angle and fruit-wing ratio had the greatest difference among groups,and the classification results were consistent with the results of correlation analysis and principal component analysis.【Conclusion】Leaf length,leaf width,length of left lower fissure,left width of leaf base,wing length,fruit length,trace length,fruit thickness,open angle and fruit-wing ratio can be used as the classification basis for distinguishing A.mono and A.truncatum.Among them,fruit length,open angle and fruit-wing ratio were the core classification traits of the two Acer species.The individual has morphological characteristics of fruit length≤10 mm,open angle≥114°and fruit-wing ratio≥1.6 can be identified as A.mono and which of fruit length≥14 mm,open angle≤84°and fruit-wing ratio≤0.9 can be identified as A.truncatum.This study provided standards and basis for the interspecific identification of phenotypic traits and the construction of the classification system for Acer species.