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

Abstract: 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, 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, Xwmc419-1 B-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.