基于主成分分析的玉米杂交组合脱水性综合评价

Comprehensive evaluation of dehydration of maize hybrid combinations based on principal component analysis

【目的】综合评价36份玉米杂交组合产量性状与收获时籽粒脱水速率快慢,筛选出籽粒脱水性快的品种,为选育高代群体育种材料提供依据。【方法】以4份玉米自交系为测验种,9份玉米高代系为待测系,采用NCII不完全双列杂交组配设计,对其籽粒脱水速率及产量性状进行相关性、主成分、隶属函数、聚类分析等进行综合评价。【结果】玉米杂交组合各性状的变异系数从小到大排序依次为生育期<株高<穗粗<穗行数<轴粗<百粒重<行粒数<穗长<穗高<穗轴含水率<单株粒重<籽粒脱水速率<收获时籽粒含水率<苞叶含水率<籽粒脱水含水率<秃尖长,秃尖长为64.63%、籽粒脱水含水率27.31%,生育期仅为1.39%。收获时籽粒含水率与株高、穗粗、行粒数和生育期呈极显著正相关。籽粒脱水速率与株高、穗粗和行粒数均呈显著负相关,与生育期和穗轴含水率呈极显著负相关。前8个主成分的特征向量值和贡献率达到了86.39%。【结论】筛选出7个脱水快利于机械收获的玉米杂交组合。

【Objective】To study the yield traits of 36 maize hybrid combinations and do a comprehensive evaluation of the rate of grain dehydration at harvest in the hope of selecting the varieties with fast grain dehydration,for the breeding of sports materials of high generation group.【Methods】Using 4 maize inbred lines as test species and 9 maize high generation lines as pending test lines,NCII incomplete double-diallel hybrid group was adopted to comprehensively evaluate the correlation,principal component,membership function and cluster analysis of grain dehydration rate and yield characters.【Results】The results showed that the order of variation coefficients of various characters in the hybrid combination was as follows:growth period<plant height<ear diameter<number of rows per ear<shaft diameter<hundred-grain weight<number of grains per row<ear length<ear height<corncob water content<single grain weight<grain dehydration rate<grain water content at harvest<bract water content<grain dehydration water content<bald tip length;and the bald tip length was 64.63%and grain dehydration water content was 27.31%,the growth period was only 1.39%.The grain water content at harvest was positively correlated with plant height,ear diameter,grain number per row and growth period.The grain dehydration rate after maturity is significantly negatively correlated with plant height,ear diameter,grain number per row and growth period was extremely significantly negatively correlated with the corncob water content at maturity.The characteristic vector-value and contribution rate of the first eight principal components reached 86.39%.【Conclusion】According to the contribution rate of each comprehensive index,based on the comprehensive index of cluster analysis,7 hybrid combinations with fast dehydration have been selected,which is conducive to mechanical harvest.These excellent combinations have utilization value in breeding.