32份早熟禾种质资源表型性状遗传多样性分析

Phenotypic diversity analysis of 32 Poa germplasm resources

本研究以32份早熟禾(Poa)种质资源为研究对象,利用多样性分析、相关性分析、主成分分析和聚类分析,评价其表型性状的变异水平,为青藏高原高寒地区早熟禾种质资源的品种选育提供依据。结果表明:通过多样性分析,遗传多样性指数最高的是总生物量(H′=2.21),变异系数最大的是株高(31.70%),其次是根长(22.04%)、总生物量(19.21%)和茎粗(16.38%);通过主成分分析得出第1主成分贡献率最大(30.274%),载荷量由高到低分别是花序长(0.748)、叶面积(0.746)、叶宽(0.705)、茎粗(0.704);通过聚类分析和综合得分,将资源分为Ⅲ大类,第Ⅰ类具有植株高大、茎叶比大、花序多,茎秆粗壮等特点,筛选出18-182、18-004、17-060这3份材料适合在饲草生产、混播草地等方面应用;第Ⅱ类具有植株矮小、叶片短而宽等特点,筛选出14-061这1份材料适合在生态恢复方面加以利用;第Ⅲ类具有植株矮小、叶片长而窄、生物量大等特点,筛选出17-105、17-332、18-064、18-139、15-048、17-044这6份材料可作为观赏利用型目标亲本进行品种培育。

In this study,we analyzed the phenotypic diversity of 32 Poa germplasm resources.Diversity,correlation,principal component,and cluster analyses were used to evaluate the variation in phenotypic traits,which provided the basis for the breeding of Poa germplasm resources in the alpine region of the Qinghai-Tibet Plateau.The highest genetic diversity index was for total biomass(H′=2.21),and the highest coefficient of variation was for plant height(31.70%),followed by root length(22.04%),total biomass(19.21%),and stem diameter(16.38%).Through principal component analysis,the contribution rate of the first principal component was found to be 30.274%.The load was the highest for inflorescence length(0.748),followed by leaf area(0.746),leaf width(0.705),and stem diameter(0.704).The resources were divided into three categories based on cluster analysis and comprehensive score.The first category was characterized by tall plants,large stem leaf ratios,more inflorescences,and thick stems.Three germplasms,18-182,18-004,and 17-060,from this category were selected for forage production and mixed grassland.The second category was characterized by short plants and,short and wide leaves,and 14-061 from this category was selected for ecological restoration.The third category was characterized by short plants,long and narrow leaves,and large amounts of biomass.Six germplasms,17-105,17-332,18-064,18-139,15-048,and 17-044 from this category were selected to provide theoretical basis for the good benefit of turf establishment.