429份玉米种质籽粒物理及品质性状综合评价

Identification and comprehensive evaluation of seed physical andquality traits of 429 maize germplasms

为科学评价不同玉米自交系的育种应用潜力,测定了429份玉米自交系的10个籽粒农艺性状表型值,并采用相关性分析、主成分分析、聚类分析和逐步回归分析构建不同玉米自交系综合评价模型,筛选优异种质材料。结果表明:10个农艺性状的变异系数范围为3.6%~40.4%。籽粒质量和淀粉含量与籽粒营养含量呈负相关。主成分分析将10个农艺性状转化为4个主成分,累计贡献率为79.8%,第1主成分为籽粒大小因子、第2主成分为营养因子、第3主成分为质量因子、第4主成分为赖氨酸因子。聚类分析将429份玉米自交系划分为5类,其中自交系W284被单独聚为一类,其物理性状为5个类群中的最高值,在籽粒大小方面表现突出;类群3具有油脂、蛋白质、赖氨酸含量高的特点。将综合得分排名前50位的玉米自交系再次聚类划分成具有不同种质特性的5个类群,得到在品质质量方面有较大遗传优势的DY358F自交系和6个质量好、丰产性高的优质玉米种质(PHV53、DK625F、HM2F、P267-4、Hong 2、B1M-6-PMO/4CV-31-1)。逐步回归分析表明,粒面积、百粒重、容重3个性状可作为玉米籽粒质量综合评价的关键指标。

The objective of this study was to scientifically evaluate the breeding application potential of maize inbred lines.Phenotypic values of 10 agronomic traits of 429 maize inbred lines were measured for correlation analysis,principal component analysis,cluster analysis and stepwise regression analysis.The comprehensive evaluation model for different maize inbred lines was established to screen the quality germplasm materials.The results showed that the coefficient of variation for the 10 agronomic traits ranged from 3.6% to 40.4%.Seed quality and starch content were negatively correlated with seed nutrient content.Principal component analysis simplified the ten agronomic traits into four principal components,showing the cumulative contribution rate of 79.8%.The first principal component was kernel size factor,the second principal component was nutrient factor,the third principal component was quality factor,and the fourth principal component was lysine content factor.429 inbred lines were divided into five groups by cluster analysis.Group 1(W284) exhibited the most prominent physical traits among the five groups and demonstrated exceptional performance in grain size.Group 3 had the characteristics of high oil content,high protein content and high lysine content.The top 50 maize inbred lines were clustered again and divided into five groups with different germplasm characteristics.The DY358F inbred line was obtained,which has a large genetic advantage in terms of quality and quantity.Six high-quality maize germplasm with good quality and high productivity,namely PHV53,DK625F,HM2F,P267-4,Hong 2,and B1M-6-PMO/4CV-31-1,were discovered.Stepwise regression analysis identified grain area,100-kernel weight,and volumetric weight as key indicators for the comprehensive evaluation of maize kernel quality.