烤烟耐烤性的遗传效应

【目的】变褐时间是衡量烟叶耐烤性的一个重要指标，对其分析并阐明烤烟耐烤性遗传效应。【方法】通过在暗箱试验中统计烟叶变褐比例，算出变褐指数（BI=∑B/n）作为耐烤性量化标准，并应用主基因+多基因混合遗传模型的6世代联合分析方法，对2个杂交组合（云烟85×大白筋599和中烟100×翠碧1号）的6个世代群体（P1、P2、F1、B1、B2和F2）中部叶烤烟耐烤性状进行遗传分析。【结果】供试组合的烤烟品种耐烤性的遗传符合E-0模型，即由2对加性-显性-上位性主基因+加性-显性-上位性多基因混合控制。主基因都以负向加性效应为主，主基因遗传率都较高，其中F2群体最高；多基因遗传率都较低。【结论】基于烤烟品种耐烤性的遗传效应，重视亲本材料和高世代对耐烤性的选择是十分必要的。

Genetic Effects of Holding Curing Potential in Flue-Cured Tobacco

【Objective】 The browning time is an important indicator to measure the holding potential of flue-cured tobacco. This property has long been exploited to elucidate the genetic effects of holding potential in flue-cured tobacco.【Method】The quantifying standard was formulated by observing and calculating the browning indexes (BI = ∑ B/n) via an experiment under dark condition. The holding curing potential of 6 generations (P1, P2, F1, F2, B1 and B2 ) derived from two crosses (Yunyan85×Dabaijin599 and Zhongyan100×Cuibi1) were genetically analyzed with the mixed major-gene plus polygene inheritance model. 【Result】The holding curing potential of flue-cured tobacco was largely controlled by two major genes having additive-dominance- epistatic effect along with polygenes having additive-dominance-epistatic effects (Model E-0). The two major genes controlling the holding potential were found having negative additive effect. The heritability of all major genes was higher for the two crosses and the F2 generation showed the highest heritability. The heritability of polygenes was lower than major genes in all the segregating generations.【Conclusion】 Based on the genetic effects of holding potential of flue-cured tobacco varieties, it is essential to pay special attention to the parental material and the high generation in selecting the holding curing potential trait.