小麦株高QTL的定位及对重要农艺性状的多效性分析

株高作为小麦育种的重要指标，对产量具有较大的影响。为进一步挖掘小麦株高的数量性状位点（quantitative trait loci，QTL），本研究以扬麦12和偃展1号杂交得到的包含205个家系的重组自交系（recombinant inbred lines，RIL）群体为材料，利用小麦55K SNP芯片构建高密度遗传图谱，结合 3年共6个环境的表型数据对株高性状进行QTL定位分析。结果表明，在染色体2B（1）、4B（1）、4D（1）、5A（1）、5B（1）和7D（2）上共检测到7个与株高相关的QTL。QPh.yaas-4B、QPh.yaas-5A和QPh.yaas-7D.1的矮秆效应来源于扬麦12，其余4个QTL的矮秆效应来源于偃展1号。在6个环境下都能检测到的位点是QPh.yaas-4B和QPh.yaas-4D，对株高的贡献率分别14.50%~24.09%和19.01%~29.80%，经过比对发现，这2个QTL分别是Rht1和Rht2。QPh.yaas-5A在5个环境下被检测到，对株高的贡献率为3.29%~5.36%；QPh.yaas-2D和QPh.yaas-7D.2在4个环境中均被检测到，对株高的贡献率分别为3.45%~6.14%和3.16%~4.10%；QPh.yaas-5B和QPh.yaas-7D.1分别在2个和3个环境中被检测到，对株高的贡献率分别是2.27%~5.09%和2.72%~4.82%。QTL比较分析后发现，QPh.yaas-7D.1和QPh.yaas-7D.2可能是新的株高位点。研究Rht-B1和Rht-D1对千粒重、穗长和穗粒数的效应，发现Rht-B1位点对这些农艺性状无显著效应，Rht-D1位点仅对千粒重有显著效应，其株高增效等位变异可显著增加千粒重。在自然群体中验证Rht-B1和Rht-D1的效应结果与RIL群体结果一致。

QTL Mapping of Wheat Plant Height and Analysis of Their Genetic Effects on Important Agronomic Traits

As an important index of wheat breeding, plant height (PH) has great influence on yield. In order to further explore the quantitative trait loci (QTL) of PH in wheat, a recombinant inbred line (RIL) population consisting of 205 lines was constructed by crossing Yangmai 12 (YM12) and Yanzhan 1 (YZ1).55K SNP chip was used to construct the highly density genetic map of wheat, and QTL for PH traits were analyzed based on data from six environments in three years. Seven QTL related to PH were detected on chromosomes 2B (1), 4B (1), 4D (1), 5A (1), 5B (1) and 7D (2). The dwarfing alleles of QPh.yaas-4B, QPh.yaas-5A, and QPh.yaas-7D.1 were derived from YM12, and the dwarfing alleles of the other four PH QTL were derived from YZ1. QPh.yaas-4B and QPh.yaas-4D were detected in all environments, explaining the phenotypic variation explained rates of 14.50%-24.09% and 19.01%-29.80%, respectively. QPh.yaas-4B and QPh.yaas-4D are Rht1 and Rht2, respectively. QPh.yaas-5A was detected in five environments, with PVE ranging from 3.29% to 5.36%. QPh.yaas-2D and QPh.yaas-7D.2 were detected in four environments, with PVE ranging from 3.45%-6.14% and 3.16%-4.10%, respectively. QPh.yaas-5B and QPh.yaas-7D.1 were detected in two and three environments, with PVE ranging from 2.27%-5.09 % and 2.72%-4.82%, respectively. QPh.yaas-7D.1 and QPh.yaas-7D.2 may be two novel PH QTL after comparison with the previously published PH QTL. To investigate the effects of Rht-B1 and Rht-D1 on thousand-grain weight, spike length and grain number per spike, it was found that Rht-B1 had no significant effect on the above agronomic traits; Rht-D1 had significant effect only on TGW, with the increased PH and TGW. Validation of the effect results of Rht-B1 and Rht-D1 in the natural population was consistent with that in the RIL population.