玉米穗轴颜色性状的遗传研究

Genetic Study on Ear Axis Color Traits of Maize

以两个轴色不同的玉米自交系自330和PH4CV构成的六世代群体为材料,采用目测法将穗轴颜色分级,通过P1、P2、F1、F2、B1和B2六个世代联合分析法,研究控制玉米轴色性状的基因分离规律。结果表明,该性状在B1和F2群体轴色数值频率表现为W型分布,B2群体数值频率表现为偏正态分布,说明玉米轴色性状遗传为少数主基因控制,符合加性-显性-上位性两对主基因遗传模型(即B-1模型);两个主基因加性效应值分别为0.72和-0.82,说明育种值较高;显性效应值分别为0.745和0.13,说明基因a对基因b表现为显性效应;在上位性中,两对基因显性×显性效应值为-0.715,说明互作效应明显,显性效应起主要作用;两对主基因的遗传率很高,达到94%以上。这一研究结果为玉米育种中轴色性状选择提供理论依据。

Six generations of different ear axis color maize inbred lines Zi330 and PH4CV were used in the study,ear axis color was classed by eyeballing.P1,P2,F1,F2,B1 and B2 were used to study the inheritance of maize ear axis color with joint analysis of multiple generations.The results were as follows：maize ear axis color trait presented ＂w＂ distribution in the B1 and F2 population,and partial normal distribution in the B1 populations,indicating that the trait was controlled by few major genes;the inheritance of maize ear axis color trait fitted the model of additive-dominance-epitasis two pairs of major genes（B-1Model）;the additive effects of the major genes a and b were 0.72 and-0.82 respectively which showed a high breeding value;the dominant effects were 0.745 and 0.13 respectively,it expressed gene a showed dominant to gene b;the epistemic effect of dominant dominant of two pair of major genes was-0.715,it improved that dominant effects played a major role;Signify inheritabilities of major genes reached 94%.All these provided a theoretical basis for maize breeding.