烤烟烟叶钾含量的遗传效应分析

Analysis of Genetic Effects of Potassium Content in Flue-Cured Tobacco

选用烟叶钾含量不同的5个烤烟基因型为亲本,按照Griffing第Ⅱ种设计方法组配成5×5双列杂交组合,利用盆栽试验研究钾素供应充足时烤烟旺长期烟叶钾含量的遗传规律。结果表明:15个烤烟基因型旺长期烟叶钾含量存在显著差异,亲本一般配合力方差和F_1特殊配合力方差均达到极显著水平,表明在这一性状的遗传中加性和非加性效应基因共同起作用。并且,烟叶钾含量的广义遗传率为71.84%,狭义遗传率为33.09%,表明遗传效应在表型中起重要作用,其中显性遗传效应占主导地位;10个F_1杂交组合中70%的组合表现出中亲优势,该性状杂种优势较强,可以利用这一特点培育烟叶钾含量高的基因型;秦烟96、农大203和农大202等3个亲本的一般配合力均较高,是提高烤烟烟叶钾含量的较为理想的亲本。

15 hybrids were goten by crossing 5 genotypes of flue-cured tobacco with different potassium content selected according to Griffing II model. The research on genetic effects was conducted for potassium content in leaf in fast-growing stage of flue-cured tobacco under plenty of potash via pot cultivating method. According to the results, there were significant differences in potassium content in leaf in fast-growing stage of 15 flue-cured tobacco genotypes, and the variance of the general combining ability and special combining ability both reached the extremely significant level, suggesting that additive and non-additive genes work together in the inheritance of this trait. Its broad-sense heritability was 71.84% and its narrow-sense heritability was 33.09%, indicating that the variance was mainly controlled by genetic factors. The heritability of potassium content of flue-cured tobacco was mainly controlled by dominance effect, and the heterosis of F1 generation was also stronger： 70% of F1 combinations showed a mid- parent advantage. High potassium content flue-cured tobacco could be obtained through heterosis utilization. Qinyan 96, Nongda 203 and Nongda 202 could be choosen as materials to breed flue-cured tobacco varieties （lines） of high potassium content for their high general combining ability.