摘要： 为了培育果穗不露顶玉米品种，以长露顶玉米自交系WZ06X97和不露顶玉米自交系WZ098杂交获得的6个世代（P₁、P₂、F₁、B₁、B₂和F₂）株系为材料，运用植物数量性状主基因＋多基因遗传模型，对玉米果穗露顶进行遗传分析。结果显示，玉米果穗露顶的最适遗传模型是E-0，即2对加性-显性-上位性主基因+加性-显性-上位性多基因。2对主基因加性效应值均为4.615，显性效应值分别是-0.680和-0.742，主基因遗传率在B₁、B₂和F₂中分别是60.41%，81.28%和83.99%，多基因遗传率分别为16.74%，5.90%和5.04%，环境方差占表型方差的比例分别为22.85%，12.82%和10.97%；上述结果表明，玉米果穗露顶受环境影响较小，主要受2对主基因和多基因控制，F₂世代主基因遗传率较高，因此育种上可在早期世代对果穗露顶性状进行选择。

关键词: 玉米, 露顶, 主基因＋多基因, 遗传效应

Abstract: In order to breed the corn ear with bract enveloped cob, the mixed major gene plus polygene inheritance model was used to investigate the inheritance law of cob exposed bract in maize in six generations (P₁, P₂, F₁, B₁, B₂, and F₂) derived from WZ06X97 line (with long cob exposed bract)×WZ098 (with bract enveloped cob). The results showed that the cob exposed bract was fitted the genetic model of E-0, i.e., two pairs of additive-dominant-epistatic major gene plus additive-dominant-epistatic polygene model. The additive effects of two major genes of cob exposed bract were all 4.615, and the dominant effects of two major genes were -0.680 and -0.742, respectively.The heritability in B₁, B₂, and F₂ was 60.41%, 81.28%, and 83.99%, respectively for the major genes, and 16.74%, 5.90%, and 5.04%, respectively for the polygenes. The variance of the environment accounted for 22.85%, 12.82%, 10.97% of the phenotypic variation of three generations, respectively. A conclusion could be made that the cob exposed bract in maize was contorolled by two major genes and polygenes, smally affected by environment. Since a higher value of h²_mg was detected in F₂ populations, selection in early generations might be an effective way for cob exposed bract breeding in maize.

Key words: Maize, Cob exposed bract, Major gene plus polygene, Genetic effects

中图分类号: 

• S513.03