籼稻整精米率QTLs的检测及上位性和环境互作效应分析

Study on Epistatic and Q×E Effects of QTLs for Indica Head Milled Ratio

利用所构建的明恢86×佳辐占重组自交系(RIL),采用混合线性模型和复合区间作图法(CIM),对不同年份不同季节获得的整精米率性状(HR)进行QTL定位及上位性和环境互作(Q×E)效应分析.检测到2个控制HR的加性效应QTL,分别位于第2、7染色体上的RM154-RM485和RM248-RM234区间,贡献率分别为1.92%、7.85%,总贡献率为9.78%.另检测到3对上位性效应区间,其中只有位于第4号染色体上的RM335-RM518区间和第6号染色体上的RM340-RM439区间互作贡献率为3.66%,其余两对的贡献率为0.环境效应检测中发现,两加性效应QTL与环境互作的贡献率分别为5.70%、8.74%,总贡献率为14.44%;上位性效应QTL与环境互作的总贡献率为2.94%.说明整精米率性状的遗传受环境因素的影响较大.

QTL mapping for head milled ratio （HR） trait of rice in different seasons and years were analyzed by using a mixed model approaches and composite interval mapping methods（CIM） in MJ recombination inbred lines （RIL）. Epistatic effects and QTL×enviroment interaction （Q× E） were also investigated. It was shown that two additive QTLs for HR were located in RM154- RM485 and RM248-RM234 intervals on the chromosome 2 and 7, with contribution ratio （H^2） respective of 1.92% and 7.85%, and the total H^2 of 9.78%. Furthermore, three pairs of epistatic effect areas were detected. The epistatic effect between RM335-RM518 on chromosome 4 and RM340-RM439 on chromosome 6 was 3.66%, and the rest were 0. In Q× E effects analysis, the H^2 of two additive QTLs interacting with enviroment were 5.70% and 8.74% respectively, and the total H^2 was14.44%. The total H^2 of the epistatic QTLs interacting with enviroment was 2.94%. In summary, Q× E effects played a control role in the heredity of HR trait in MJ RILs.