15份多花黑麦草优良引进种质的表型变异分析

多花黑麦草(Lolium multiflorum Lam.)是世界栽培牧草中的优良禾本科牧草。为更好地利用多花黑麦草种质资源,本研究对引自国外的15份多花黑麦草种质的15个形态性状和农艺性状进行了变异系数、相关性分析、主成分分析和聚类分析。结果表明:15份材料间存在较大变异,除单株干重外,其余性状在供试材料间均表现出显著性差异,变异系数范围为10.28%~39.15%,变异系数平均值为19.49%,从小到大依次为小穗数小穗长株高分蘖数千粒重花序长倒二叶长小花数茎粗第一节间长倒二叶宽旗叶宽旗叶长单株干重单株鲜重。主成分结果表明,前5个主成分累积贡献率达到84.51%,第1主成分以株高为主要特征;第2主成分以旗叶和倒二叶长、宽为主要特征;第3主成分以花序长和小花数为主要特征;第4主成分以千粒重为主要特征;第5主成分以产草量为主要特征。15份种质材料经基于欧氏距离的UPGMA聚类分析被划分为3大类,类别间存在较显著的差异,其中第2类因其植株高大、叶片宽大的特点,具备选育高产种质的潜力。

Analysis of Phenotypic Variations in 15 Introduced Elite Germplasm of Lolium multiflorum

Abstract: Lolium multiflorum is a wildly cultivated temperate forage grass in the world. In order to screen elite ryegrass germplasm resources, variation coefficient, correlation analysis, principal component analysis and cluster analysis were conducted to analyze the 15 phenotypic traits for 15 intruduced L.multiflorum accessions. The results showed high phenotypic variability among the 15 studied accessions, and significant difference was seen in most of characters except dry matter yield . The variant coefficient varied from 10.28% to 39.15% with an average of 19.49%, in descending order, by spikelets, length of spikelets, plant height, tiller number, 1000-kernel weight, panicle length, length of penultimate leaf, number of florets per spikelet, stem diameter, length of first internode, width of penultimate leaf, width of flag leaf, length of flag leaf, dry matter yield per plant and fresh matter yield per plant. Principal components analysis of 15 traits showed the cumulative proportion of top 5 principal components reached 84.50% with plant height as the first component, leaf traits as the second component, inflorescence characters as the third component, 1000-kernel weight as the fourth component, and forage yield as the fifth component. Cluster analysis based on Euclidean distance showed that the 15 annual ryegrass accessions could be divided into 3 groups, among which there were significant differences for most traits. The second group had the high yield potential in elite germplasm screening.