利用高世代回交群体检测水稻垩白相关性状QTL

[目的] 探究水稻垩白性状,为水稻垩白形成分子机制研究和水稻品质育种提供材料。[方法] 通过高产品种’桂朝2号’与低垩白优质品种’越光’连续回交和分子标记辅助选择方法,构建一套包含71个家系的高世代回交群体,分别在2013年南京和2014年海南对其垩白粒率和垩白度2个性状进行表型调查和QTL检测。[结果] 南京和海南两年两地垩白粒率和垩白度2个性状都存在显著相关。两年两地共检测到33个与垩白粒率相关的QTL,其中 5个QTL在2个环境中重复检测到,分别位于第4染色体RM1359~RM16939和SSR11~RM17332区间,第5染色体RM13~RM430区间,第7染色体RM5344~RM6872区间,以及第8染色体RM152~RS73区间。两年两地共检测到了17个与垩白度相关的QTL,其中3个QTL能够重复检测到,分别位于第4染色体RM1359~RM16939区间,第8染色体RM152~RS73区间,以及第10染色体RM467~RM271区间,且有2个位点与垩白粒率位点重合。同时发现定位QTL中,有7个QTL属于一因多效,对垩白粒率及垩白度都有一定影响。[结论] 本文共检测到50个垩白性状相关的QTL,其中有7个位点能够被重复检测到,其中控制垩白粒率的qPGWC4.1、qPGWC4、qPGWC7.1,控制垩白度的qDPGWC4.1、qDPGWC8.1和qDPGWC10.1,是新的QTL。
[Objectives] The paper aims to analyze the rice chalkiness character and create materials for studying the molecular mechanisms of rice chalkiness in rice quality breeding. [Methods] In the present study a set of 71 advanced backcrossing population was constructed using high quality and low chalky variety’Koshihikarias’donor parent,high yield and high chalky variety’Guichao 2’as recurrent parent by continuous backcrossing and molecular marker assisted selection. The chalkiness phenotypes including the percentage of grains with chalkiness(PGWC)and degree of percentage of grains with chalkiness(DPGWC)were investigated and the quantitative trait loci(QTL)of advanced backcross population were detected in 2014 Nanjing and 2015 Hainan,respectively. [Results] The results showed that PGWC and DPGWC were significantly associated,and thirty-three PGWC QTL were detected in more than one year. Among them five could be detected repeatedly in two different environments. In addition,seventeen DPGWC QTL were detected in two different environments,three of them can be detected repeatedly,among them two are coincided with PGWC sites. Moreover,seven pleiotropic QTL had the same impacts on the PGWC and DPGWC. [Conclusions] Through two years of phenotype and molecules data of chalky trait,50 QTL were detected,and seven were detected in both two years at Nanjing and Hainan. In addition,the controlling PGWC QTL qPGWC4.1,qPGWC4,qPGWC7.1 and the controlling DPGWC QTL qDPGWC4.1,qDPGWC8.1,qDPGWC10.1 might be new findings in this study