小麦籽粒品质性状的QTL分析

QTL Mapping for Grain Quality Traits in Wheat

利用小麦中国春（母本）和兰考大粒（父本）F2群体构建了169个标记的分子遗传图谱，将F2∶3家系分别种植于3个环境中，利用基于完备区间混合模型的单环境作图模型和多环境作图模型对小麦籽粒容重、硬度、蛋白含量和结合水含量性状进行了QTL分析。结果显示：（1）两种作图模型下，检测到容重的6个共同QTL（QTW-6B-6、QTW-7B-6、QTW-7B-9、QTW-5D-2、QTW-6D-1、QTW-6D-4），单环境模型下遗传贡献率为1.99%～6.57%，多环境模型下遗传贡献率为3.66%～20.07%，其中QMTW-7B-9、QMTW-6D-1和QMTW-6D-4在多环境模型中表现为主效QTL。（2）检测到硬度的3个共同QTL（QHD-4A-5、QHD-7A-1和QHD-7B-9），单环境模型下的遗传贡献率为6.00%～6.95%，多环境模型中遗传贡献率为5.43%～9.64%。（3）检测到蛋白含量1个共同QTL（QPR-6D-1），单环境模型下的遗传贡献率为5.39%，多环境模型中遗传贡献率为10.06%，表现为主效QTL。（4）检测到籽粒结合水含量1个共同QTL（QMO-1B-4），单环境模型下的遗传贡献率为39.20%，多环境模型下的遗传贡献率为75.01%，均表现为主效QTL。（5）1B染色体上存在同时控制籽粒容重、硬度、蛋白和结合水含量的QTL，说明1B染色体对小麦品质的影响可能很大。研究表明，小麦容重、硬度、蛋白含量、结合水含量的遗传主要受加性效应控制。该研究初步定位的一些重要QTL可为进一步精细定位、基因挖掘和育种早代品质性状分子标记辅助选择提供依据。

In the present study,a total of 327 F2 lines from the cross between two common wheat Chinese Spring（female）×Lankaodali were planted in Qianxian,Qishan and Yangling of Shaanxi Province,respectively.Test weight,hardness,protein content and bound moisture content were evaluated.A genetic map was constructed based on 167 SSRs and 2 EST markers.QTL analysis was conducted with single environment model and multi-environment model by the software QTL-ICIMapping V.3.2.The results showed that：（1）In two mapping models,6 QTLs（QTW-6B-6,QTW-7B-6,QTW-7B-9,QTW-5D-2,QTW-6D-1,QTW-6D-4） were found for test weight,explaining 1.99%~6.57% of phenotypic variance in single-environment model,whereas accounting for 3.66%~20.07% of phenotypic variance in multi-environment model.And QMTW-7B-9,QMTW-6D-1 and QMTW-6D-4 showed major QTL in multi-environment model;（2）3 QTLs （QHD-4A-5,QHD-7A-1 and QHD-7B-9） were detected for hardness,and in single-environment model it explain phenotypic variance from 6.00% to 6.95%,while in multi-environment model it explain phenotypic variance account for 5.43%~9.64%;（3）1 QTL（QPR-6D-1） for protein content was mapping on 6D chromosome,explaining 5.39% and 10.06% of phenotypic variance in single-environment model and multi-environment model,respectively;（4）1 QTL for moisture content was detected explaining 39.20% and 75.01% of phenotypic variance in single environment model and multi environment model,respectively;（5）The QTLs controlling test weight,hardness,protein content and bound moisture content were mapping on 1B chromosome,indicating the big influences of 1B on these traits.Test weight,seed hardness,protein content and moisture content are mainly controlled by additive effects.The identified molecular markers related to these quality traits in this study will benefit for marker-assisted selection in breeding programs.