小麦产量性状的QTL分析

Analysis of QTLs for Yield Traits of Wheat

为寻找更多与小麦产量性状相关的数量性状位点（QTL），利用江苏地方品种望水白与墨西哥小麦品种Alondra杂交构建的重组自交系群体（104个家系），在3个试验环境下进行了单株有效穗数、主穗粒数、单穗粒数和千粒重4个性状的QTL分析，结果在5A染色体上检测到与单株有效穗数相关、可以解释10．3％～18．8％表型变异的QTL1个；检测到与主穗粒数相关的QTL8个，分别位于染色体1B、1D、3B、4A、5D、6B上和连锁群4上（未知具体染色体归属），单个QTL可以解释9．9％～19．9％的表型变异；检测到与单穗粒数相关的QTL11个，分别位于染色体1B、1D、2A、2B、3B、4A、5D、6B和7A上，单个QTL可解释7．5％～43．4％的表型变异；检测到与千粒重相关的QTL5个，分别位于2A、2B、3B、4D和7A染色体上，单个QTL可解释9．6％～25．7％的表型变异。获得的QTL可以用于分子标记辅助育种。

The yield traits of wheat were very important for breeding and wheat production,but most of them were quantitatively inherited parameters. The objectives of this study were to find more QTLs for yield traits of wheat and to apply them in the variety improvement and marker-assisted breeding. Tiller number per plant （TPP）, kernel number of major spike （KPMS）, kernel number per spike （KPS） and 1000-kernel weight （TKWT） of 104 recombinant inbred lines （RILs） from a cross between Wangshuibai （a Jiangsu landrace） and Alondra （ a Mexico variety） were assessed in the field trails at two locations in 1998, 2000 and 2003. With the methods of interval mapping and MQM mapping, a QTL located on chromosome 5A for TPP was detected and able to explain 10.3%-18.8% of pheno- typic variation. 8 QTLs on chromosome 1B, 1D, 3B, 4A, 5D, 6B（2）and linkage group 4 （the exact chromosome unknown） and 11 QTLs on chromosome 1B, 1D, 2A, 2B, 3B（2）, 4A, 5D, 6B（2）and 7A were found for KPMS and KPS, explaining 9.9%-19.9% and 7.5%-43.4%of phenotypic varia- tion, respectively. Among these QTLs, 5 QTLs on chromosome 3B, 4A, 5D and 6B（2） were the same between KPMS and KPS. 5 QTLs associated with TKWT were detected on chromosome 2A, 2B, 3B, 4D and 7A, each QTL was able to explain 9.6%-25.7% of phenotypic variation respectively. These QTLs detected in this study could be useful in future marker-assisted-selection programs.