Abstract: In order to investigate the relationship between agronomic traits and yield formation in annual ryegrass (Lolium multiflorum),to evaluate the genetic parameters of each trait,to clarify the main trait factors of yield formation,and to screen the comprehensive evaluation indexes of traits. In this experiment,the comprehensive evaluation of agronomic traits and yield of 17 Lolium multiflorum varieties (lines) was carried out by using analysis of variance,analysis of genetic parameters,correlation analysis,principal component analysis,linear regression analysis,path analysis and cluster analysis. The results showed that the coefficients of variation for each trait of annual ryegrass ranged from 3.70% (flowering time) to 24.85% (seed yield per plant);the diversity indices ranged from 1.611 (Second leaf width) to 2.007 (thousand-grain weight);and the broad-sense heritability and the relative genetic progress of the flag-leaf width,stem thickness,thousand-grain weight,and seed yield per plant were higher,which made their application in breeding selection more effective. Regression analysis and through-train analysis showed that flag leaf width had the greatest direct effect on hay yield per plant and seed yield per plant. Cluster analysis classified the 17 multiflora ryegrass varieties (lines) into three classes,among which the three materials contained in Class I had excellent comprehensive traits,which could be used as spare materials for subsequent breeding utilization and parent selection.

Key words: Lolium multiflorum, Agronomic traits, Seed yield per plant, Forage yield per plant, Integrated evaluation

摘要： 为探究多花黑麦草(Lolium multiflorum)农艺性状与产量形成的关系，评估各性状的遗传参数，明确产量形成的主要性状因子，筛选性状综合评价指标。本试验运用变异分析、遗传参数分析、相关分析、主成分分析、线性回归分析、通径分析及聚类分析对17份多花黑麦草品种(系)农艺性状与产量进行综合评价。结果表明：多花黑麦草各性状变异系数介于3.70%(开花期)～24.85%(单株种子产量)之间；多样性指数范围在1.611(倒二叶宽)～2.007(千粒重)之间；旗叶宽、茎粗、千粒重及单株种子产量广义遗传力和相对遗传进度较高，其在育种选择中的应用效果较好。回归分析及通径分析表明：旗叶宽对单株干草产量及单株种子产量的直接影响最大。聚类分析将17份多花黑麦草品种(系)分为3类，其中第Ⅰ类包含的3份材料综合性状表现优秀，可作为后续育种利用及亲本选配的备用材料。

关键词: 多花黑麦草, 农艺性状, 单株种子产量, 单株草产量, 综合评价