淮山药种质资源主要农艺性状遗传多样性分析

【目的】探讨我国不同地区淮山药种质资源农艺性状的遗传多样性、亲缘关系及分类特征,为淮山药品种选育及生产利用提供参考。【方法】对收集的44份淮山药种质资源的19个农艺性状进行调查,通过遗传多样性分析、聚类分析与主成分分析,探讨其遗传多样性、亲缘关系及分类特征。【结果】44份淮山药种质资源形态性状间具有较高的多样性。在12个质量性状中,遗传多样性指数最高的是叶形（1.53）,其次是薯皮颜色（1.51）;薯形的频率分布最高（93.18%）,其次为薯肉颜色（90.91%）和茎蔓形状（81.82%）。在7个数量性状中,多样性指数最高的是薯块长度（1.89）,其次是生育期（1.84）和薯块径粗（1.77）;变异系数最大的是单株产量（79.25%）,其次为薯块径粗（42.21%）和单株结薯数（35.62%）,最小的为生育期（17.57%）。根据各农艺性状的遗传差异,可将44份淮山药种质聚为四大类群;第Ⅰ类群种质均来源于广西,可作为有增产潜力的加工型亲本材料;第Ⅱ类群种质主要来源于广西,可作为高产选育目标亲本;第Ⅲ类群种质主要来自南方地区,均是人工栽培的野生类型品种,为一般性亲本;第Ⅳ类群种质主要来源于北方省区的种质,可作为一般性早熟选育亲本。主成分分析结果表明,前6个主成分累计贡献率达83.73%,第一主成分反映高产株型综合因子,第二主成分反映加工株型因子,第三主成分反映植株结薯因子,第四、五、六主成分分别反映薯块、薯皮颜色和茎蔓颜色因子。【结论】我国淮山药主要地方栽培种质资源间农艺性状差异明显,具有丰富的遗传多样性,其亲缘关系呈现一定地域生态环境规律;南方地区在品种选育中应注重对第一、第二主成分的选择。

Genetic diversity analysis of main agronomic traits in yam germplasm resources

【Objective】The genetic diversity, genetic relationship and classification characteristics of agronomic traits in different yam germplasm resources collected from different regions of China were analyzed in order to provide references for variety breeding and production utilization of yam. 【Method】The 19 agronomic traits of 44 collected yam germplasm resources were investigated to conduct genetic diversity analysis, cluster analysis and principal component analysis for exploring their genetic diversity, genetic relationship and classification characteristics. 【Result 】The results showed that different morphological traits of 44 collected yam germplasm resources presented higher diversity. Amongst 12 qualitative traits, the genetic diversity index of leaf shape was the highest（1.53）, followed by tuber skin color（1.51）. The frequency distribution of tuber shape was the highest（93.18%）, followed by tuber flesh color（90.91%） and stem shape（81.82%）. Amongst 7 quantitative traits, the genetic diversity index of tuber length was the highest（1.89）, followed by growth duration（1.84） and tuber diameter（1.77）. Among different traits, the variation coefficient of yield per plant was the highest（79.25%）, followed by tuber diameter（42.21%） and tubers per plant（35.62%）, the lowest was found to be growth period（17.57%）. According to genetic differences of different agronomic traits, 44 yam germplasm resources could be clustered into 4 groups. All the materials of the first and second groups were derived from Guangxi, and could be used as processing parent materials with potential of increasing yield, and high-yield variety breeding parents, respectively. The third group materials were mainly derived from southern China, which was artificial cultivation wild species and could be used as general parent. And the fourth group materials were derived from north provinces of China and could be used as common early-maturing variety breeding parents. The principal component analy