烤烟几个主要根系生理特性的遗传效应分析

Analysis of Genetic Effects of Physiological Characteristics of Root in Flue-cured Tobacco

采用盆栽试验,选用5个烟叶钾含量不同的烤烟品种,按照GriffingⅡ组配成15个双列杂交组合,研究了充足供钾条件下烤烟旺长期4个主要根系生理特性的遗传效应。结果表明,4个根系生理性状在不同基因型间差异显著,一般配合力和特殊配合力方差也达到极显著水平,广义遗传率较高,均大于60%,性状的变异主要由基因效应控制。其中,烤烟根体积和根系阳离子交换量(CEC)的遗传以基因的加性效应为主,狭义遗传率较高,提高烤烟根系量和根系CEC育种在早代进行选择效果较好;烤烟根系活力和ATP酶活性的遗传以基因的显性效应为主,F1杂种优势较强,可以利用杂种优势获得根系活力大、ATP酶活性强的基因型;农大202、农大203和秦烟96的一般配合力均较高,是提高根系吸钾能力的较为理想的亲本;F1杂交组合中农大203×NC628和云烟85×NC628根系生理特性的综合表现较好,可作为选育烤烟钾素高效吸收基因型的材料。

Fifteen hybrids were obtained by crossing5different genotypes of flue-cured tobacco with different potassium content selected according to the GriffingⅡmodel.Genetic effects of4main physiological characteristics of root were analyzed at the fast-growing stage of flue-cured tobacco under plenty of potash via pot cultivating method.According to the results,there were significant differences between general combining ability and special combining ability of the4traits.Their broad-sense heritability was over60%,indicating that variance in these traits was mainly controlled by genetic factors.The heritability of root volume and CEC of flue-cured tobacco was mainly controlled by additive effects,suggesting that in breeding tobacco cultivars for high-volume and high-CEC,selection at early generations is more efficient.The heritability of root vigor and ATPase activity of flue-cured tobacco was mainly controlled by dominance effects,and the heterosis of F1generation was also stronger.High-vigor and high-activity of ATPase could be obtained by heterosis utilization.Nongda203×NC628and Yunyan85×NC628could be chosen as materials to breed for nutrient efficient flue-cured tobacco varieties(lines)for their good comprehensive performance.