Abstract: To clarify the genetic diversity of nutritional organ phenotype of oat (Avena sativa) germplasm resources and the correlations among the phenotypic traits, and provide a scientific basis for oat breeding and innovative utilization of germplasm resources, this study evaluated and analyzed the genetic diversity of aboveground organ quality traits, stem traits, leaf traits, and tiller traits of oat in Huangzhong District, Xining City, Qinghai Province. 590 oat germplasm resources collected from home and abroad was evaluated using the methods of correlation analysis and cluster analysis The results showed that the genetic diversity index of qualitative traits was the highest in the node hairiness (1.026), while the lowest in seedling type (0.162). The genetic diversity index of quantitative traits was the highest in the third internode diameter (2.09), while the lowest in flag leaf area (1.87). The coefficient of variation was the largest in tiller number (54.92%), while the smallest in internode number (12.20%). The traits related to stem characteristics and the length of penultimate leaf and the area of penultimate leaf were important factors influencing oat seed and forage yield. The 590 oat germplasm resources were divided into four clusters by cluster analysis. Cluster III could be used as parent materials for forage breeding goals, and Cluster IV could be used as lodging-resistant materials for breeding.

Key words: Covered oats, Stem traits, Leaf traits, Phenotypic traits, Genetic diversity

摘要： 为明确燕麦（Avena sativa）种质资源营养器官表型性状的遗传多样性和各性状之间的相关关系，进而为燕麦育种和种质资源创新利用提供理论依据，本研究以国内外收集的590份燕麦种质资源为研究对象，在青海省西宁市湟中区对其从地上器官质量性状、茎部性状、叶部性状和分蘖性状的遗传多样性进行评价分析，并利用相关性分析和聚类分析方法，评价其营养器官表型性状的遗传变异水平。结果表明：590份燕麦种质资源质量性状遗传多样性指数以茎节绒毛最高（1.026），苗期株型最低（0.162）；数量性状的遗传多样性指数以第三茎节茎粗最高（2.09），旗叶叶面积最低（1.87）；变异系数以无效分蘖数（54.92%）最大，茎节数最小（12.20%）；茎部性状和倒二叶长、倒二叶叶面积是影响燕麦种子和饲草产量的重要因子。590份燕麦资源可分为4大类群，其中类群III可作为饲草型育种目标的亲本材料，类群IV可作为抗倒伏育种材料。

关键词: 皮燕麦, 茎部性状, 叶部性状, 表型性状, 遗传多样性