青贮玉米生物产量及植株性状的配合力分析

Analysis of combining ability on biomass yield and plant characters for silage maize

选用9个玉米自交系按Griffing4双列杂交模式组配36个杂交组合,采用完全随机区组设计进行田间试验,分析蜡熟期生物产量及主要植株性状的配合力。结果表明,生物产量一般配合力以南60-1最高,M9、CML161次之,这些自交系均为温、热带系;特殊配合力表现较好的组合有CML161×P42c9MH4-1-2-2-B-1-1、M9×掖478、南60-1×P44c10MH17-32-2-B-3-2等,符合热带系×亚热带系或热带系×温带系的杂优模式。通过对各性状特殊配合力的相关性、遗传力进行分析,结果表明,生物产量与株高、茎粗、穗位叶面积、节间数相关性较大;狭义遗传力较高的为穗位高、株高、节间数和穗下位绿叶数。因此,自交系性状选择应以株高、节间数为主,穗下位绿叶数次之,对生物产量直接选择的效果较小。

Nine inbred maize lines were combined to 36 combinations by Griffing 4 diallel cross model, and the combing ability of biomass yield and plant characters at dough stage were analyzed by complete randomized block design in field. The results showed that the general combining ability of biomass yield for Nan 60-1 was the highest in all combinations, then M9 and CML161, and these inbred lines was tropical line. The special combining ability of the combinations CML161×P42c9MH4-1-2-2-B-I-1, M9 × Ye 478, Nan 60-1×P44c10MH17-32-2-B-3-2 were better and according with the cross model such as tropical line x subtropical line or tropical line x temperate line. The correlation and heritability analysis of special combining ability for all characters indicated that the correlations between biomass yield and plant height, stalk diameter, area of ear leaves, and nodes were obvious, and the narrow hefitability of ear height, plant height, nodes and green leaves below ear was higher. Therefore, the main selection of characters for inbred lines should be plant height and nodes, then green leaves below ear, and the effect of direct selection on biomass yield was lower.