马铃薯重要农艺性状的相关性、主成分与聚类分析

为明确国内外马铃薯种质资源在云南大春季的表现,本研究对68份马铃薯品种(系)的出苗率、长势、主茎数、茎粗、株高、开花性、病情发展曲线下面积(area under disease progress curve, AUDPC)、成熟期、商品率、单株块茎数、单株块茎重、平均块茎重、匍匐茎数量、匍匐茎长度共14个农艺性状进行相关性、主成分与聚类分析。结果表明:单株块茎数、AUDPC、单株块茎重、开花性的变异程度较明显,变异系数分别为50.42%、43.91%、39.81%和39.67%;单株块茎重与长势、茎粗、株高、开花性、商品率、平均块茎重、匍匐茎数量极显著正相关,与单株块茎数显著正相关,与成熟期极显著负相关。AUDPC与成熟期极显著正相关且相关系数达到0.802。在主成分分析中,前6个主成分方差累积贡献率为83.290%,可用来代替14个农艺性状指标。聚类分析将68份马铃薯品种(系)分为3个类群,Ⅰ类群表现为晚熟、高抗晚疫病病,Ⅱ类群表现为中熟、中抗晚疫病,第Ⅲ类群表现为早熟感晚疫病。本研究结果为云南大春马铃薯种质资源的合理利用提供了科学依据。

Correlation,Principal Component and Cluster Analysis for Agronomic Traits of Potato Varieties or Clones

In order to clarify the performance of potato germplasm and varieties collected from domestic and abroad at Yunnan in spring season.Correlation,principal components,and cluster analysis were conducted to analyze 14 major agronomic traits including emergence rate,plant vigor,main stem number,stem thickness,plant height,extent of flowering,AUDPC(Area under disease progress curve),maturity,commodity rate,tuber number per plant,tuber weight per plant,average tuber weight,stolon number and stolon length.It was observed that the coefficient of variation of tuber number per plant,AUDPC,tuber weight per plant and extent of flowering were 50.42%,43.91%,39.81%and 39.67%,respectively.The correlation analysis revealed significant positive correlation among tuber weight per plant,plant vigor,stem thickness,plant height,extent of flowering,commodity rate,average tuber weight,stolon number and tuber number per plant,and had significantly negative correlation with maturity.There was a high correlation between AUDPC and maturity(with coefficient of variation 0.802).The principal component analysis results showed that the six eigenvalues could replace fourteen agronomic traits for phenotyping as cumulative variance proportion reached 83.290%.The 68 potato genotypes could be classified into three clusters.The cluster Ⅰ was mainly contained late maturing germplasm with high late blight resistance,Cluster Ⅱ was mainly composed of middle-maturing germplasm,with middle late blight resistance.Cluster Ⅲ was mainly early maturing germplasm,with low late blight resistance.The results provide theoretical basis for the germplasm improvement and variety development in Yunnan spring season.