多环境条件下超级杂交稻协优9308重组自交系群体粒形性状的QTL分析

QTL Analysis of Rice Grain Shape Traits by Using Recombinant Inbred Lines from Super Hybrid Rice Xieyou 9308 in Multi-environments

利用超级杂交稻协优9308的重组自交系群体及建立的遗传连锁图谱，在3个环境条件下对粒长（GL）、粒宽（GW）、粒厚（GT）、籽粒体积（GV）和籽粒长宽比（GI。WR）等5个粒形性状的数量性状基因座（QTL）进行定位分析。结果表明，3个环境下共检测到26个QTL，分布在第1、2、3、4、6、7、8、10、11和12染色体上，其中粒长相关QTI。4个，贡献率为3．98％～54．58％；粒宽相关QTI．4个，贡献率为6．98％～9．88％；粒厚相关QTL8个，贡献率为4．91％～11．92％；籽粒体积相关QTI。5个，贡献率为5．07％～22．35％；籽粒长宽比相关QTL5个，贡献率为5．17％～47．81％。6个QTI。在两个以上环境被检测到，其中qGL3．1、qGW3．2、qGV3．1和qGLWR3．j在3个环境中同时被检测到，说明这4个QTI．受环境影响较小，能稳定表达。第3染色体RM6283一RM7370区间同时稳定检测到控制粒长、粒厚、体积和长宽比等4个性状的QTL。存在一因多效性。共检测到包括粒宽、粒厚和籽粒体积3个性状的5对加性×加性上位性互作qTL，但贡献率都较小，介于1．08％～3．oo％。联合检测发现，粒形性状qTI，与环境存在互作，但单个QTL与环境互作效应低，对表型变异的贡献率都较小，说明粒形性状遗传比较稳定。

The QTI.s for some grain characters including grain length （GL）, grain width （GW）, grain thickness （GT）, grain volume （GV）, grain length to width ratio （GLWR） were analyzed with Xieyou 9308-derived recombinant inbred lines （RIL） population as material by using its molecular genetic linkage map across three environments. A total of 26 QTLs were detected on chromosomes 1, 2, 3, 4, 6, 7, 8, 10, 11 and 12. Among the QTLs detected, 4 QTLs for GL explained 3.98% 54.58% of the phenotypic variation; 4 QTLs for GW explained 6.98%--9.88% of the phenotypic variation; 8 QTLs for GT explained 4.91%-11.92% of the phenotypie variation; 5 QTLs for GV explained 5.07%-- 22.35% of the phenotypic variation; 5 QTLs for GLWR explained 5.17%--47.81% of the phenotypic variation. Six QTLs could be detected in two or more environments, qGL3.1 , qGW3.2 , qGV3.1 , qGLWR3.1 could be detected across three environments, suggesting that these QTLs were less affected by the environment and were stably expressed in multi-environments. QTLs for GL, GT, GV and GLWR could be detected in the interval RM6283- RM7370 on chromosome 3, suggesting that the genetic effects of QTLs for related traits existed pleiotropic effects. A total of 5 QTL pairs with additive X additive epistatic effects for 3 traits （GW, GT, GV） were detected, explaining 1.08%- 3.00 % of phenotypic variation. Combined detection showed that additive X environment interaction effect of the QTLs for grain shape traits was detected, but all of those effects were so small and explained small phenotypic variation, suggesting that rice grain shape traits were geneticly stable.