Genetic Analysis of the Main Agronomic Traits of Flue-cured Tobacco

In order to predict the hybrid merits of flue-cured tobacco F₁ quickly and accurately, and promote the breeding of the strong advantages of hybrid combination, we used the NCII mating design approach, with seven flue-cured tobacco varieties (strain) forming 12 cross combinations, to explore the heterosis performance of some major agronomic traits about parents and F1, and to analyze their combining ability and heritability. The results showed that heterosis had large discrepancy according to different traits and hybrid combinations. The five traits sort heterosis by size order: plant height> leaf area> leaf length> leaf width> number of leaves. The group traits showed a certain negative except plant height. The study of combining ability help to select the relatively ideal hybrid combinations and parents in this research. Meanwhile, the research of parental heritability showed that each trait selection was more reliable, but non-additive heritability had a prominent influence on leaf width and leaf area traits, thus, which should to be chosen in the higher generation. Considering the heterosis and combining ability of all traits, we concluded that Jiucaiping 2 × G28 with the Nanjiang 3× Florda301 is a good combination; and Florda301 and the Jiucaiping 2 were good parents.