Abstract: Inheritance of seedcoat colour in the cross No.2127-17(yellow-seeded Brassica napus L.)/99Yu42(black-seeded) or Hui 5148-2 was studied by applying the major gene plus polygene model along with classic genetics analysis through a joint analysis of its P1,F1,P2,B1,B2 and F2 generations.The classic genetics analysis demonstrated that seedcoat colour was under the control of the maternal genotype and partially dominant nuclear gene.The joint analysis results showed that seedcoat colour was controlled by one major gene with additive dominance effects plus polygenes with additive dominance effects(Model D-1),the additive dominance effects of the major gene play a major role in the performance of seedcoat colour.The additive effects and the dominance effects were 7.58 and 2.48 in the major gene and 1.91 and 1.33 in the polygenes respectively.Heritability of seedcoat colour in B1,B2 and F2 was estimated to be 35.34%,63.27% and 60.76% for the major gene and 2.80%,7.12% and 13.29%for the polygenes.And the enviorments markedly affected the seedcoat colour expression for its 29.95%-61.86% variance ratio.

Key words: Yellow, 一seeded Brassica ncrpus L, Seedcoat colour, Inheritance, Majorgene plus polygene mixed inheri-tance

CLC Number: 

• S643.3