烤烟叶数、叶面积的遗传分析

以叶数较少、叶面积较小的烤烟品种丸叶为母本(P1),以叶数较多、叶面积较大的烤烟品种Coker319为父本,构建了6个世代分离群体,利用植物数量性状主基因+多基因混合遗传模型的联合分离分析方法,分析烤烟杂交组合丸叶×Co-ker319叶数、叶面积的遗传效应。结果表明:烤烟的叶数和叶面积均受2对加性-显性-上位性主基因+加性-显性-上位性多基因(E0)控制,其中叶数遗传以加性效应及显性×显性上位性效应为主,叶面积几种遗传效应差不多,其上位性效应>加性效应>显性效应,叶数和叶面积在B1世代的主基因遗传率分别为36.91%和2.13%,多基因遗传率分别为31.00%和19.53%,B2世代的主基因遗传率分别为51.60%和50.92%,多基因遗传率分别为16.84%和13.26%,F2世代的主基因遗传率分别为42.63%和30.32%,多基因遗传率分别为42.08%和12.18%,叶数和叶面积的主基因遗传率较高,适合在早代选择。

Genetic Analysis of Leaf number and Leaf area in Flue-cured Tobacco

The joint segregation analysis method of mixed major gene plus polygene genetic model was used to study the inheritance of leaf number and leaf area in flue-cured tobacco. Six generations (P1, P2, F1, B1, B2 and F2) from the crosses (Wanye×Coker319, Wanye with less leaves and small leaf area, Coker319 with more leaves and large leaf area) were investigated. It was found that leaf number and leaf area in flue-cured tobacco appeared to be a quantitative trait and their inheritances fitted to a mixed genetic model of two major genes with additive-dominant-epistatic effects plus polygenes with additive-dominant-epistatic effects (the E0 model). Leaf number was mainly controlled by the additive effect and the epistatic effect of dominance ?dominance. The additive, dominant and epistatic effects of leaf area was all important which the epistatic effect > the additive effect > the dominance effect. Heritabilities of the major genes were estimated to be 36.91% and 2.13% in B1, 51.60% and 50.92% in B2, 42.63% and 30.32% in F2. Heritabilities of the polygenes were estimated to be 31.00% and 19.53% in B1, 16.84% and 13.26% in B2, 42.08% and 12.18% in F2. Because of their higher heritability of the major gene, the selection of leaf number and leaf area could be taken in early generations.