以玉米自交系M9916×D472组成的6世代群体为材料，利用六世代数量性状主基因+多基因混合遗传模型多世代联合分析方法，研究玉米茎基腐病抗性的遗传机制。结果表明：分离世代的次数频率分布在F2群体中呈近似于抛物线状的正态分布，在B1和B2群体中呈偏正态分布。通过AIC值适合性检验，该性状符合一对加-显主基因+加-显-上位性多基因遗传D模型，主基因加性效应值为5.29，显性效应值为6.79，两者效应值均相对较高，加性与显性效应比率为78%；多基因加性效应为2.98，明显低于显性效应值6.88，说明显性效应起主导作用。从上位性方面来看，多基因加性互作效应明显，加、显互作上存在一定的抑制作用，显性互作效应不明显，加性互作效应在上位性方面起主导作用。回交群体中主基因的遗传率介于39.9-41.3%之间，多基因遗传率介于33.8-36.7%之间，主基因遗传率相对较高；自交群体中多基因遗传率为53.8%，大于主基因遗传率32.8%，说明在进代过程中主基因遗传率不断下降。综上所述，在抗茎基腐病的育种中，应注重早代抗病材料的选择，对现有重要的感病材料可利用回交方法进行有效改良。
英文摘要:
Six generations of maize inbred lines of M9916×D472 were selected as the research materials to study the inheritance of maize stalk rot by the mixed major gene and polygene inheritance model. The results were as follows: the frequency distribution in F2 population was similar to normal distribution, a skewed normal distribution in B1 and B2 populations. Maize stalk rot resistance trait fitted the model of a pair of additive-dominance major gene plus additive-dominance-epitasis polygene (D Model) through the group AIC value fit test. The major gene additive effect value was 5.29, dominant effect value was 6.79, their rate was 78%. The polygene additive effect was 2.98, it was lower than the dominant effect value(6.88) who played the important role. The polygene additive genetic interaction effect was obviously, the dominant interaction effect was just the opposite, it has certain inhibitory on additive-dominant interaction effect, additive interactions effect played a leading role in epitasis. The major gene heritability was between 39.9% and 41.3%, the polygene heritability was between 33.8% and 36.7% in backcross populations. The major gene heritability was 32.8%, it was lower than polygene heritability(53.8%) in selfing populations, the major gene heritability was falling on selfing process. It should be pay more attention to select early generation of disease-resistant material or put backcross breeding to improve the breeding value.
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