Abstract: To screen novel germplasm of Pennisetum purpureum with high-yield potential， 800 F₁ hybrid individuals were generated by crossing ‘Guimu 1’ hybrid P. purpureum （female parent） with F-AI P. purpureum （male parent）. SSR molecular markers were employed to authenticate true hybrids， followed by analyses of diversity， correlation， clustering， and principal components for 10 yield-related traits in the true hybrid population. The results revealed that 300 true hybrids were identified using two primer pairs （SSR24 and WSSR31）. The true hybrid population exhibited abundant phenotypic variation， with coefficients of variation ranging from 13.91% to 45.58% and diversity indices from 1.37 to 2.84. Correlation analysis demonstrated that all traits were highly significantly positively correlated with single-plant yield （P<0.01）， among which plant height showed the strongest correlations with fresh weight and dry weight， with correlation coefficients of 0.55 and 0.66， respectively. Heterosis analysis indicated that most yield-related traits of the F₁ generation displayed positive dominance， and the relative heritability of the female parent was stronger than that of the male parent. Principal component analysis extracted two principal components， accounting for a cumulative variance contribution rate of 64.819%， with plant height， single-plant dry weight， tiller number， and internode length identified as core influencing factors.

Key words: Pennisetum purpureum hybrid F₁ generation, SSR markers, Phenotypic diversity, Cluster analysis, Comprehensive evaluation

摘要： 为筛选出高产潜力的象草（Pennisetum purpureum）新种源，以‘桂牧1号’杂交象草为母本、F-AI象草为父本获得800份杂交F₁代，用SSR分子标记鉴定真假杂种，并对真杂种的10个产量相关性状开展多样性、相关性、聚类和主成分分析。结果表明：用SSR24和WSSR31两对引物鉴定出300份真杂种。真杂种群体表型变异丰富，变异系数为13.91%~45.58%，多样性指数为1.37~2.84。相关性分析显示，所有性状均与单株产量呈极显著正相关（P<0.01），其中株高与鲜重、干重的相关系数最高，为0.55和0.66。杂种优势分析表明，F₁代的产量及相关性状多为正向显性，母本的相对遗传力强于父本。主成分分析提取出2个主成分，累计贡献率为64.819%，株高、单株干重、分蘖数和节间长为核心影响因子。聚类分析将材料划分为4类，其中，第Ⅲ类群有92份材料综合性状最优，第Ⅱ类群有41份材料综合性状表现最差，第I、Ⅳ类群介于两者之间。通过模糊隶属函数法进行综合评价，筛选出15份具有高产潜力的优良育种材料。研究结果为象草杂交育种提供了方法和材料支撑。

关键词: 象草杂交F₁代, 分子标记, 多样性分析, 聚类分析, 综合评价