Abstract: In this study, the F₂ generation population constructed by the cross between the grain Sorghum bicolor ‘Xinliang 52’ and Sorghum sudanense ‘Meiyin-48’ was used as the test material. Five agronomic characteristics of the F₂ generation including leaf numbers, stem numbers, plant height, stem diameter and wax powder were measured, and the optimal genetic model and heritability of each trait were obtained by principal-multiple gene analysis. The results showed that the most suitable model for the number of leaves and stem diameter was Model A_0. There was no major gene inheritance, but the quantitative trait inheritance controlled by micro-effect and multi-gene. The optimal model of stem numbers and plant height was Model A_4, a negative full-dominant model controlled by a pair of major genes, and the major gene heritability were 91.13% and 66.14%. The optimal model of wax powder was Model B_1, which belonged to the additive-dominant-epistatic mixed genetic model, controlled by two pairs of major genes with the heritability of the major gene of 54.03%.

Key words: Sorghum bicolor×Sorghum sudanenes, agronomic characters, major-multi-gene genetic analysis, quantitative inheritance