油菜新种质12R1402主花序有效角果数的遗传

Genetics of effective silique number on main inflorescence of new germplasm 12R1402( Brassica napus L. )

为促进耐密植油菜育种,提高主花序有效角果数,分析主花序多角油菜新品系12R1402的遗传规律,用主花序有效角果数差异较大的12R1402和常规油菜品种沪油17杂交,构建4世代遗传体系(P1、P2、F1和F2),应用主基因+多基因混合遗传模型对该组合主花序有效角果数进行遗传分析。结果表明,组合12R1402×沪油17主花序有效角果数遗传受2对加性-显性-上位性主基因+加性-显性多基因控制(E-1模型),其中第1对主基因加性效应值为40.86,显性效应值为-32.62,第2对主基因的加性效应值为40.58,显性效应值为-0.75,2对主基因都以加性效应为主,都表现为主花序多角部分显性,2对主基因间存在明显的基因互作效应;多基因加性效应值为-29.40;多基因的显性效应值为68.36。12R1402×沪油17组合F2群体中主基因和多基因遗传率分别为60.38%和2.14%,主花序多角性状以主基因遗传为主,宜在早期世代进行选择。组合12R1402×沪油17遗传变异占表型变异的62.52%,环境变异占表型变异的37.48%,环境因素对主花序多角性状影响较大。

For high yield breeding under high density planting of rapeseed,effective silique number on main inflorescence was always expected. By using a new line of multi- silique on main inflorescence named 12R1402,4generations（ P1,P2,F1 and F2） were derived from a cross 12R1402 × Huyou 17. They were analyzed using mixed major gene plus polygene inheritance model to understand the inheritances of effective silique number on main inflorescence. Result showed that effective silique number on main inflorescence of 12R1402 × Huyou 17 were dominated by 2 pairs of major genes with additive- dominance- epistasis effects plus polygene with additive- dominance effects（ in E- 1 model）. The additive effects of major genes were 40. 80 and 40. 58,and the dominance effects of these 2 major genes were- 32. 62 and- 0. 75 respectively. Hereditability of major gene（ σ2mg） in F2 was 60. 38%and that of polygene（ σ2pg） was 2. 14%. It indicated that the effective silique number on main inflorescence in B.napus L. was dominated by major genes. Higher hereditability of major genes could be favorable to an efficient selection in early generations of effective silique number on main inflorescence breeding. In addition,environmental variance and genetic variance accounted for 37. 48% and 62. 52% of the phenotypic variance respectively,indicating that the environmental factors had great effects on effective silique number on main inflorescence in B. napus L.