杂交小麦亲本矮秆基因鉴定及其对杂种优势的影响

Identification of Wheat Hybrid Parents’ Dwarf Genes and Their Effects on Heterosis

为探究不同矮秆基因型对小麦杂种优势的影响和应用潜力,利用不同矮秆基因亲本配置杂交组合,在成熟期统计亲本与杂交组合的株高、单株穗数、千粒质量、单株产量等10个性状,分析不同矮秆基因型杂交组合杂种优势及株高与各调查性状的相关关系.结果表明,4种不同矮秆基因型杂交组合中部分基因型间的单株产量差异有统计学意义,Rht1′+Rht21′,Rht1′+Rht2′及Rht1″+Rht2′基因型在单株产量上有正向超高亲优势,Rht1′+Rht21′基因型在单株穗数、千粒质量、单株生物量和单株产量上超亲优势明显,除Rht1″+Rht21′基因型外,其他矮秆基因型均有在单株产量上超高亲优势达到10%以上的杂交组合.Rht1′+Rht2′和Rht1″+Rht2′两种矮杆基因型株高与单株产量均无显著相关性,单株产量与单株穗数和单株生物量呈极显著正相关.4种矮秆基因型均可不同程度地降低杂交小麦的株高,提高其抗倒伏能力.具有Rht1′+Rht21′基因型的杂交组合平均超高亲优势最大,其次是Rht1′+Rht2′基因型的杂交组合.因此,在杂交小麦育种过程中配制这两种基因型的杂交更容易获得强优势组合.

To explore the effect and application potential of different dwarf genotypes on wheat heterosis,the parents with different dwarf genes were used to configure hybrid combinations.The plant height,number of spikes per plant,1 000-grain weight,and yield per plant of the parents and hybrid were measured at maturity stage.10 traits were used to analyze the correlations between heterosis,plant heights of different dwarf genotype of hybrid combinations and investigated traits.The yield differences per plant among some genotypes in hybrid combinations of four different dwarf genotypes are significant.Rht1′+Rht21′,Rht1′+Rht2′ and Rht1″+Rht2′ genotypes had positive high heterobeltiosis on yield per plant.Rht1″+Rht21′ genotypes had distinct heterobeltiosis on number of spikes per plant,1000-grain weight,biomass and yield per plant.Except for Rht1″+Rht21′ genotypes,other dwarf genotypes had hybrid combinations with heterobeltiosis of more than 10% in yield per plant.Rht1′+Rht2′ and Rht1″+Rht2′ dwarf genotypes had no significant correlation between plant height and yield per plant,but yield per plant was still significantly positively correlated with spike number per plant and biomass per plant.The four dwarf genotypes could reduce the plant height of hybrid wheat to different degrees and improve its lodging resistance.The hybrid with the Rht1′+Rht21′ genotype had the highest average heterobeltiosis,followed by the hybrid combination with the Rht1′+Rht2′ genotype.Therefore,it is easier to obtain theheterosis combinations by formulating the hybrid combination with those two genotypes in hybrid wheat breeding.