水稻糙米蛋白质含量QTL定位及上位性分析

稻米蛋白质含量是水稻(Oryza sativaL.)营养品质育种的重要内容之一。本研究以华恢3号与中国香稻构建的重组自交系(RILs)群体为材料,构建了含有156个SSR标记的遗传连锁图谱,结合近红外分析仪测定两年(2009年,2010年)的糙米蛋白质含量,进行了QTL定位和遗传基础分析研究。两年共定位到3个控制糙米蛋白含量的QTL和16对上位性互作的位点。其中检测到的3个QTLs,分别位于第4、6、8染色体上,单个QTL解释的表型变异率为3.39%~34.2%,两年解释的总表型变异率分别为41.2%和5.95%,这些QTL中只有位于第8染色体短臂在区间RM310~RM547的qbpc8在2009年和2010年被重复检测到。LOD值分别为22.5和3.5,解释表型变异率分别为34.2%和5.95%。这些QTL的发掘,为分子标记辅助选择改良水稻营养品质奠定了基础。

QTL Mapping and Epistasis Analysis of the Protein Content in Brown Rice

The brown rice protein content (BPC) has been a major concern in rice (Oryza sativa L.) nutritional quality breeding. In this study, a linkage map consisting of 156 SSR (Simple Sequence Repeat) markers was constructed from a recombinant inbred line (RIL) population derived from cross-breeding between Zhongguoxiangdao and Huahui3. Based on the results of BPC phenotypes of RILs from both 2009 and 2010 by Near-infrared Papid Content Analyzer, more than 16 pairs of epistatic interaction loci, and a total of three quantitative trait loci (QTLs) were detected on chromosome 4, 6 and 8, respectively. Each QTL explains 3.39% to 34.2% phenotypic variation. and it explains a total of 41.2% and 5.95% phenotypic variation for 2009 and 2010, respectively. The QTL (qbpc8) flanked by RM310 and RM547 on chromosome 8 was the largest (only) one detected in both years, with LOD values of 22.5 and 3.5 andexplains 34.2% and 5.95% of phenotypic variation, respectively. These results will provide useful genetic basis for marker-assisted selection in rice quality breeding programs.