基于高密度遗传图谱的水稻糙米率QTL定位分析

QTL Analysis of Brown Rice Rate Using High-density Genetic Map in Rice

水稻糙米率是加工品质中的一个重要组成部分。为了探索糙米率的遗传基础,本研究以V20B和CPSLO17作为亲本,构建了150个重组自交系(recombinant inbred lines,RIL)群体。利用SLAF标签构建的精度更高、平均遗传距离为0.292 c M的高密度遗传图谱,结合亲本和群体糙米率表型数据,对三亚和贵阳两个环境下控制水稻糙米率的数量性状位点(quantitative trait loci,QTL)进行遗传分析。结果显示:三亚和贵阳共检测到两个QTL。其中,三亚检测到1个QTL位点q BR1,位于第1染色体Marker600937~Marker685097区间上,两个标记间遗传距离为0.471 c M,贡献率为9.7470%;贵阳检测到1个QTL位点q BR4位于第4染色体Marker503771~Marker431234区间上,两个标记间遗传距离为0.469 c M,贡献率为9.7634%。两个检测到的QTL,在两个环境中未重复检测到,且增效位点均来自于亲本V20B。本研究对进一步发掘和利用水稻糙米率QTL具有重要意义,同时为利用分子标记辅助选择提高水稻糙米率提供参考。

Brown rice rate is an important co mponent of the processing quality in rice.In order to explore the genetic basis of brown rice rate,this study constructed a population of 150 lines(recombination inbred lines,RIL)derived from a cross between V20 B and CPSLO17.Using a high-density genetic linkage map of SLAF Markers with an average distance of 0.292 c M and higher accuracy,and combination with the brown rice rate phenotype data between parents and population,the genetics analysis of QTLs that control the brown rice rate in Sanya and Guiyang was conducted.The results showed that a total of two QTLs controlling brown rice rate were detected in Sanya and Guiyang.q BR1,the QTL detected in Sanya,was located in the Marker600937~Marker685097 interval on chromosome 1 with the genetic distance of 0.471 c M and genotype contribution of 9.7470%,while q BR4,the other QTL detected in Guiyang,was locates in the Marker503771~Marker431234 on chromosome 4 with the genetic distance of 0.469 c M and genotype contribution of 9.7634%.Moreover,these two detected QTLs haven't repeatedly detected in the two environments,and their effect-increasing loci were both originated from V20 B.Therefore,the results is of great significance for further exploring and utilizing brown rice rate related QTL,and also useful in improvement of brown rice rate by marker-assisted selection.