18个玉米杂交组合主要农艺性状与产量的多元分析

Multivariate Analysis of Main Agronomic Traits and Yield of 18 Maize Hybrid Combinations

为了探讨玉米主要农艺性状与产量之间的关系,深入研究种质资源并筛选出适宜文山及相似生态区域的抗病优质高产广适玉米新品种,同时提高新品种培育的效率,本研究以自主选育的18份玉米杂交组合为试验材料,通过随机区组试验,对17个主要农艺性状进行鉴定,采用方差分析、相关性分析、通径分析、主成分分析和聚类分析对其进行比较和综合评价。结果表明:供试材料产量性状差异较大,18个玉米杂交组合产量在10 082.5~12 759.5 kg·hm^-2之间,其中有11个杂交组合的产量均显著高于对照(WD004)(P<0.01),WD012和WD006产量最高。参试材料的17个农艺性状的遗传多样性丰富,变异系数在3.79%~127.52%之间;相关分析表明,产量与单穗粒质量(r=0.659**)、出籽率(r=0.525*)和穗长(r=0.473*)均呈显著正相关;通径分析表明,出籽率和单穗粒质量对产量的直接正向作用分别是0.484和0.477,表明出籽率和单穗粒质量对产量的提高作用最大。主成分分析表明,玉米的17个主要农艺性状简化为6个综合指标,其累积贡献率为85.461%,代表了17个农艺性状改良方向,根据主成分的综合得分进行聚类,在欧氏距离10处将18个玉米品种(系)分成4类,有效区分了不同的品种。因此,在选育高产优质玉米品种时,按育种目标的要求选取主要性状,同时也要注意与其他性状间的关联。

This research aimed to explore the relationship between main agronomic traits and yield of maize, to guide the in-depth study of germplasm resources and to screen out new varieties of maize with high quality, high yield and disease resistance which were suitable for Wenshan and similar ecological regions. Meanwhile the efficiency of breeding of new varieties was improved. In this study,17 main agronomic traits were identified by random block test using 18 maize hybrid combinations selected previously as experimental materials. Variance analysis, correlation analysis, path analysis, principal component analysis and cluster analysis were conducted for the comparison and comprehensive evaluation of these agronomic traits. The results showed that: yields of the 18 maize hybrids varied significantly, ranging between 10 082.5 and 12 759.5 kg·hm^-2 and the yields of 11 maize hybrids were significantly higher than that of the control(WD004)(P<0.01), among which the yield of WD012 and WD006 were the highest;the genetic diversity of 17 agronomic traits was rich: the coefficient of variation was between 3.79% and 127.52%;correlation analysis showed that yield was positively correlated with grain weight per panicle(r = 0.659*), yield was also positively correlated with grains(r = 0.525*) and panicle length(r =0.473*);path analysis showed that the direct positive effects of seed yield and grain weight per panicle on yield were 0.484 and 0.477,respectively, indicating that seed yield and grain weight per panicle had the greatest effect on yield improvement;principal component analysis showed that the 17 main agronomic traits of maize were simplified to 6 comprehensive indexes, and the cumulative contribution rate was 85.461% representing the direction of improvement of these 17 main agronomic traits. 18 maize varieties were clustered into four categories at 10 Euclidean distance basing on the comprehensive scores of principal component analysis and different varieties were effectively distinguished. Therefore, in the breeding of maize varieties with high quality and high yield, the main traits should be selected according to the requirements of breeding objectives, meanwhile the correlation with other traits should also be concerned.