利用SSR和SNP标记分析鲁麦14对青农2号的遗传贡献

鲁麦14既是大面积推广品种,又是育种骨干亲本,衍生了40多个品种,其中青农2号(鲁麦14/烟农15//矮秆麦)是近年审定的小麦品种。本研究利用350个SSR标记和小麦90k芯片检测的26 026个SNP标记,解析了鲁麦14对青农2号的遗传贡献。鲁麦14和烟农15分别含有1/4和1/2蚰包麦血统,基因组分子标记分析结果显示,这两个品种有55.42%的SSR位点一致,而SNP位点一致性高达71.53%。选择亲本间差异位点,分析鲁麦14和烟农15对青农2号的遗传贡献,结果表明鲁麦14对青农2号的贡献大于烟农15,青农2号与亲本鲁麦14、烟农15分子标记的一致性,SSR标记分别为54.11%和36.30%,SNP标记分别为72.55%和26.98%。依据高通量SNP标记结果,从染色体水平看,烟农15贡献率超过50%的染色体有2B、3B和6A;而鲁麦14在除此之外的18条染色体的遗传贡献率大于50%。青农2号遗传组成图谱揭示了遗传物质多以较大染色体片段形式从亲本传递至子代。对亲本和子代进行多年多点的农艺性状调查,发现青农2号的旗叶长、旗叶宽、穗下节间长、穗叶距、抽穗度等株型相关性状及千粒重、粒长等产量相关性状与鲁麦14相近,株高、生育期等性状与烟农15相近。本文从分子层面解析育种亲本对子代的遗传贡献,为分子标记辅助育种提供了依据和理论基础。

Genetic Contribution of Lumai 14 to Qingnong 2 Revealed by SSR and SNP Markers

Lumai 14, a widely planted wheat variety, is the parents of more than 40 bread wheat varieties, among which Qingnong 2 (Lumai 14/Yannong 15//Aiganmai) has been released in recent years. In this study, the inheritance from Lumai 14 to Qingnong 2 was evaluated using 350 SSR markers and 26 026 SNPs detected by iSelect 90k SNP array. Pedigrees show that Lumai 14 and Yannong 15 contain 1/4 and 1/2 blood of Youbaomai, respectively. Genomic marker screening confirmed that Lumai 14 and Yannong 15 shared 55.42% common SSR loci and 71.53% common SNP loci. Polymorphic markers between them were used to disclose that Qingnong 2 inherited more SSR and SNP loci from Lumai 14 (54.11% and 72.55%, respectively) than from Yannong 15 (36.30% and 26.98%, respectively). In Qingnong 2, chromosomes 2B, 3B, and 6A harbored more than 50% SNPs from Yannong 15, whereas, the remaining 18 chromosomes carried more than 50% SNPs from Lumai 14. The parental genetic compositions were present mainly in large chromosomal segments in Qingnong 2. Phenotyping investigation in multi-locations across years indicated that Qingnong 2 was similar to Lumai 14 in length and width of flag leaf, length of first internode, length from flag leaf pulvinus to spike base, earing degree, thousand-grain weight, and grain length, and similar to Yanong 15 in plant height and growth duration. This results provide valuable information for molecular marker-assisted selection in wheat breeding.