鹅观草表型性状变异与生境间的相关性

Correlation Analysis between the Variation of Phenotypic Characters and the Habitat of Roegneria kamoji Ohwi

根据鹅观草(2n=6x=42)资源的地理分布特点,采用T检验、变异系数、主成分分析、相关分析和聚类分析法对来自四川、新疆、宁夏、内蒙古、甘肃和山西的40个居群进行表型多样性分析。结果表明,表型性状无论在居群内还是居群间均表现出显著差异(p<0.01)。主成分分析显示,株高、穗长、旗叶长、旗叶宽、小穗数、小花数穗下第一节间长和穗轴第一节长等8个性状是引起鹅观草表型性状变异的最主要因素;这8个表型性状与海拔高度、年平均温度和纬度的相关程度较高。聚类分析结果表明,以遗传距离18.72为分界线可将40个居群分为三类,第一类只包括1个居群,其株高、穗长和穗下第一节间长为40个居群中最高、最长的植株;第二类包含20个居群,具有植株矮小、穗短、叶片窄小、小穗数少等特点;第三类包含19个居群,该类植株与第二类植物相比较,具有植株高大、叶片较长、较宽、小穗数和小花数较多、穗下节间长等特点。

Based on the natural distribution of Roegneria karnoji Ohwi in China , by means of T Test,coefficient variation,principal component, UPGMA cluster and partial correlation analysis, 40 populations of Roegneria karnoji Ohwi from Sichuan, Xinjiang, Ningxia, Inner Mongolia, Gansu and Shanxi were evaluated by their phenotypic diversities. The results showed that whether among populations or within populations, phenotypic characters diversities of Roegneria karnoji Ohwi were significant different ; The eight phenotypic traits such as plant high , spike length,flag leaf length,flag leaf width,spikelet number,floret number,the first internode length under spike and rachis internode length were the main factors affecting phenotypic characters; The correlations between the eight phenotypic traits and ecological and geographic factors such as altitude,AMT and latitude were significant. The 40 populations were divided into 3 groups based on genetic distance of 18. 67 by cluster analysis, the first cluster was composed of one population whose plant heigh, spike length and the first internode length under spike were the longest of 40 populations, the second groups contained 20 populations with shorter plants high and shorter spike length and fewer spikelet number, the third cluster contained 19 populations with higher plant , wider leaf width, longer leaf length, more spikelet number, more floret number.