谷子不育系高146A不育与早抽穗性状遗传关系分析

为了研究杂交组合(高146A×K103)的P₁、P₂、F₁和F₂ 世代群体对不育系高146A早抽穗性状的遗传特点,本研究利用主基因+多基因混合遗传模型,并且采用χ₂测验方法对不育基因与早抽穗控制基因间的遗传关系进行了研究。结果表明：高146A早抽穗性状表现为一数量性状,其遗传符合两对加性-显性-上位性主基因 加性-显性多基因遗传模型,以主基因作用为主,多基因的作用相对较小,其中一对主基因的加性、显性起主要作用,另一个主基因的显性和上位性效有较大作用；在F₂群体中,雄性不育和早抽穗两性状共有早熟可育、早熟不育、晚熟可育和晚熟不育等四种表型,表型分离比例符合三对基因独立遗传分配规律(分离比例为39：13：9：3；χ₂=3.18 <χ_20.05=7.81),这些结果表明控制该雄性不育系高146A的不育和早抽穗性状的三对基因为独立遗传,无连锁关系。

Genetic Relationship Analysis Between Infertility and Early-heading Date Trait in Gao 146A, A Highly Male-sterile Line of Foxtail Millet [Setaria italica (L. Beauv.)]

Genetic characteristics of the early-heading date in Gao 146A, a highly male-sterile line, were analyzed using the major gene plus polygene mixed inheritance model with the P1, P2, F1 and F2 generations derived from the hybrid Gao 146A × K103, and the genetic relationship between infertility and early-heading date was studied using χ2 test methods in this paper. The results showed that the early-heading trait in Gao 146A was a quantitative trait, and was controlled by two pairs of additive - dominance - epistatic major genes plus additive - dominance polygenic model, and the major gene effects is large, but the multi-gene effect is relatively small, in which a pair of main additive genes played the major role in either additive or dominant effect, and another major gene had a second role in dominant and epistatic effect. There were four kinds of phenotypes of the sterility and heading date in the F2 population, namely early-heading-fertile type, early-heading-infertility type, late-heading-fertile type and late-heading-infertility type, and the segregation ratio was 39:13:9:3, in line with the independently distribution law of three pairs of genes (χ2 = 3.18 < χ20.05 = 7.81). These results suggest that there pairs of genes controlling the male-sterile and early-heading traits respectively are of independent inheritance and non-linkage relationship.