宁春4号×河东乌麦F2∶5家系遗传图谱构建与籽粒蛋白质性状QTL分析

为适应宁夏回族自治区小麦绿色优质高效品种选育和产业提质增效的需求,以宁春4号与河东乌麦杂交后代的248个F_2∶5家系为材料,对其进行遗传图谱构建与籽粒蛋白质数量性状基因座(quantitative trait locus,QTL)分析,以期为该地区小麦蛋白质性状遗传改良提供育种中间材料和QTL。结果表明:用197个SSR(simple sequence repeats)标记构建了包括小麦21条染色体的分子遗传图谱,总长度为2 342.63 cM,标记间平均距离为11.89 cM;蛋白质性状在F_2∶5家系出现较大分离,粗蛋白质含量、湿面筋含量的群体平均值(分别为14.49%、30.96%)介于双亲该性状之间,稳定时间的群体平均值(10.86 min)均超过高亲;粗蛋白质含量、稳定时间、湿面筋含量的超中亲比例分别达50.81%、77.82%、50.00%,超高亲比例分别达21.77%、59.27%、22.98%;籽粒蛋白质性状3个指标间均呈极显著正相关(P﹤0.01)。利用22个标记共检测到36个籽粒蛋白质QTL,分别为14个粗蛋白质含量QTL、6个稳定时间QTL和16个湿面筋含量QTL,涉及1A、2A、3A、5A、7A、1B、2B、6B、1D、2D、3D、4D、5D、6D、7D等15条染色体,36个QTL的连锁系数(LOD值)最大为14.9,表型贡献率为3%~6%,加性效应为-1.71~1.17,有11个标记所在的位点存在籽粒蛋白质性状QTL富集区。

Construction of genetic map and analysis of QTL for grain protein traits using F2∶5 pedigrees derived from Ningchun No.4×Hedong black wheat

To adapt to the demand about green high quality and efficient cultivar breeding of wheat, and industry improving for Ningxia Hui Autonomous Region, using 248 F_2∶5 pedigrees of Ningchun No.4 × Hedong black wheat as materials, their genetic map was constructed, and grain protein traits QTL (quantitative trait locus) were analyzed, so as to provide breeding intermediate materials and QTL for genetic improvement of wheat protein traits in this area. The results showed that a molecular genetic map of 21 chromosomes in wheat was constructed using 197 SSR (simple sequence repeats) markers, the total length was 2 342.63 cM with an average interval distance of 11.89 cM. The distribution of quality traits in F_2∶5 pedigrees were significantly separated. Average values of crude protein content (14.49%) and wet gluten content (30.96%) were between those of high-parent and low-parent, the average value of stabilization time (10.86 min) was over the high parents. The proportion of over mid-parent was 50.81%, 77.82% and 50.00% in crude protein content, stabilization time and wet gluten content, respectively; Proportions of ultra-high parents was 21.77%, 59.27% and 22.98%, respectively. There was significantly positive correlation among three grain protein trait indices. 36 QTL loci of grain protein traits were explored by 22 SSR markers, there were 14 QTL, 6 QTL and 16 QTL of crude protein content, stabilization time and wet gluten content, respectively, those involved in chromosomes 1A, 2A, 3A, 5A, 7A, 1B, 2B, 6B, 1D, 2D, 3D, 4D, 5D, 6D and 7D, maximum logarithm of odds (LOD) score of these 36 QTL was 14.9, the contribution rates to phenotype were from 3% to 6%, their additive effects were from -1.71 to 1.17, and QTL enrichment regions of grain protein traits existed in 11 marker loci.