青藏高原垂穗披碱草种质资源形态多样性分析

Study on Morphological Diversity of Elymus nutans Germplasm Resources from Qinghai-Tibetan Plateau

对来自青藏高原（四川、西藏、甘肃、青海及新疆）的54份垂穗披碱草种质资源进行了形态多样性研究。选取了30个形态学性状对供试材料进行了连续3年的观察测定。结果表明：供试材料的各性状的变异系数变化范围为7.25%~33.89%,平均变异系数为16.05%,Shannon多样性指数变化范围为1.6996~2.5487,平均值为2.2118,揭示了供试的垂穗披碱草种质资源具有丰富的形态学变异水平。基于欧式距离对供试材料进行UPGMA聚类分析,结果将供试材料划分为高大、中等、低矮等类型。而主成分分析结果表明前8个主成分的特征值较高,能够解释总体变异的76.67%,其中株高、小穗长、颖片长、外稃长、茎长等形态性状具有较高的特征向量值,这些性状指标基本上可以揭示供试垂穗披碱草种质资源的形态总体表现。

The morphological diversity of 54 Elymus nutans germplasm resources from Qinghai-Tibetan Plateau including Sichuan,Tibet,Gansu,Qinghai and Xinjiang province were conducted in the study based on 30 morphological traits during 2007~2009.The results showed that the coefficients of variation of the morphological traits ranged from 7.25% to 33.89% with an average of 16.05%,the ShannonWeaver diversity index ranged from 1.6996 to 2.5487 with a mean of 2.2118,which revealed a wealth of phenotypic variation among the materials.Based on the morphological variation data,the UPGMA cluster analysis were carried out using the Euclidean distance in NTSYS software.The accessions were divided into several parts including low-,medium-and tall-types plants.Additionally,the principal component analysis based on morphological data indicated that the first 8principal component eigen values were relatively high,which could explain the 76.67% of the total variation.The principal component analysis also indicated that length of glume,height,stem length,spikelet length,length of lemma were the main sources of variation,which could mostly reveal the trend of morphological variation of Elymus nutans germplasm.