小麦骨干亲本“胜利麦/燕大1817”杂交组合后代衍生品种遗传构成解析

Molecular Dissection of Core Parental Cross "Triumph/Yanda 1817" and Its Derivatives in Wheat Breeding Program

小麦地方品种燕大1817是我国小麦育种骨干亲本之一，胜利麦/燕大1817杂交组合是北部冬麦区小麦品种遗传改良的基础组合。利用随机分布于小麦全基因组21条染色体上的175对在胜利麦和燕大1817间具有多态性的SSR标记（每条染色体平均8.3对）分析了燕大1817和胜利麦对其38份后代衍生品种的遗传贡献率。结果表明，在全基因组水平上，燕大1817对其后代衍生品种贡献率为26.8%，胜利麦对其后代衍生品种贡献率为43.6%；在部分同源群水平上，燕大1817对其后代衍生品种A、B和D基因组的贡献率分别为25.9%、25.7和26.4%，胜利麦对其后代衍生品种A、B和D基因组的贡献率分别为46.1%、39.1%和44.0%。说明引进种质对我国北部冬麦区小麦品种遗传改良起了重要作用。在染色体水平上，胜利麦对其后代衍生品种的21条染色体贡献率在20.0%~63.3%间，其中对1A染色体贡献率仅有20.0%，对7A染色体贡献率高达63.3%。骨干亲本燕大1817对其后代衍生品种的21条染色体贡献率在7.5%~44.2%间，其中对2A染色体贡献率仅有7.5%，对7D染色体贡献率可达44.2%。骨干亲本燕大1817对后代衍生品种贡献率较高的基因组（单元型）区段有7个，分别是3A上的Xwmc11–Xcfa2262、7B上的Xbarc1073–Xwmc475、1AL上的Xgwm357–Xwmc312、7DS上的Xbarc305–Xwmc506、4AS上的 Xgwm165–Xgwm610、1B上的Xwmc419–Xwmc134和2D上的Xcfd56–Xbarc228，其中，3A染色体上的Xwmc11–Xcfa2262区段对衍生品种贡献率高达77.5%。而胜利麦对后代衍生品种贡献率较高的基因组（单元型）区段有8个，分别是6BS上的Xwmc105－Xwmc397、3D上的Xgdm72–Xgdm8、2DS上的Xgdm5–Xgwm455、7AL上的Xbarc121–Xgwm332、5DL上的Xgwm174–Xwmc161、5BL上的 Xgwm499–Xbarc308、5A上的Xbarc141–Xgwm291和4BL上的Xgwm66–Xgwm251，其中6BS上的Xwmc105–Xwmc397区段对衍生品种的贡献率最高，达71.3%。这些基因组（单元型）区段上存在许多与产量、抗病、抗逆和适应性等重要农艺性状相关的基因和QTL，对北部冬麦区小麦品种遗传改良可能起了重要作用。

Wheat landrace Yanda 1817 is one of the ‘core parental’ breeding lines for North China Winter Wheat Breeding Program during 1950–1960. The derivatives of cross Triumph/Yanda 1817 have been widely planted in the area and, thereafter, used as parental lines to make further crosses for new varieties development. In this study, the genetic contributions of core parental lines Yanda 1817 and Triumph to their derivative cultivars were analyzed using 175 polymorphic SSR markers randomly distributed on the 21 chromosomes of wheat genome with an average of 8.3 markers per chromosome. The results indicated that Triumph （43.6%） contributed more genetic components than Yanda 1817 （26.8%） to their derivatives on the whole genome level. On the A, B and D subgenome levels, triumph had the contribution ratio of 46.1%, 39.1% and 44.0%, While Yanda 1817 only had the contribution ratio of 25.9%, 25.7% and 26.4% to their derivatives, respectively. It revealed that exogenous germplasm played an important role in the improvement of wheat varieties in the North China Winter Wheat Breeding Program. As for single chromosomes, 20.0% （1A） to 63.3% （7A） of Triumph alleles and 7.5% （2A） to 44.2% （7D） of Yanda 1817 alleles could be detected on the derivative cultivars. Seven Yanda 1817 genomic （haplotypic） regions, Xwmc11-3A–Xcfa2262, Xbarc1073-7B–Xwmc475, Xgwm357-1AL–Xwmc312, Xbarc305-7DS–Xwmc506, Xgwm165-4AS–Xgwm610, Xwmc419-1B–Xwmc134, and Xcfd56-2D–Xbarc228, and eight Triumph genomic （haplotypic） regions, Xwmc105-6BS–Xwmc397, Xgdm72-3D–Xgdm8, Xgdm5-2DS–Xgwm455, Xbarc121-7AL–Xgwm332, Xgwm174-5DL–Xwmc161, Xgwm499-5BL–Xbarc308, Xbarc141-5A–Xgwm291, and Xgwm66-4BL–Xgwm251, were found to be significantly important in the Triumph/Yanda 1817 derivative cultivars. Genomic （haplotypic） regions Xwmc11-3A–Xcfa2262 derived from Yanda 1817 and Xwmc105-6BS–Xwmc397 derived from Triumph had the contribution ratio of 77.5% and 71.3%, respectively to the derivative cultivars of Triumph/Yanda 1817, indicating they are important targets for selection in breeding program. Agronomic important genes and QTLs relevant to yield, disease resistance, tolerance to abiotic stresses and adaptation to diversified environments located on these genomic （haplotypic） regions are important targets for new varieties development in the North China Winter Wheat Breeding Program.