水稻顶部三叶与穗重的关系及其QTL分析

QTL and Correlation Analysis on Characters of Top Three Leaves and Panicle Weight in Rice (Oryza sativa)

对水稻汕优63重组自交系群体顶部3张叶片的长、宽、重和单穗重等10个性状进行了相关分析和QTL定位.穗重与9个叶片性状存在极显著的正相关,其中与倒2叶重的相关系数最大,剑叶重次之.所有性状在重组自交系群体中均存在双向超亲分离,接近正态分布.共检测到44个主效QTL和43对双位点互作影响上述10个性状.主效QTL分布于水稻的除第8染色体外的其余11条染色体上,贡献率介于3.19%～26.23%;互作分布于水稻的12条染色体上,贡献率变幅为2.03%～8.93%.第2染色体的R2510-RM211标记区间同时检测到控制单穗重和倒2叶重的QTL,该QTL对超级稻株型育种具有应用价值.

The correlation and QTL analysis on top three leaves and panicle weight as source-sink traits were conducted on 241 RIL population derived from an elite hybrid rice Shanyou 63. The correlations between grain weight per panicle and all the leaf traits were significantly positive. The biggest correlation coefficient was found between grain weight per panicle and the second leaf weight, followed by the flag leaf weight. The frequency of these traits was approximately normally distributed with tremendous transgressive segregation. A total of 44 main effect QTLs and 43 digenic epistatic loci related to these traits were detected. These main effect QTLs were located on 11 out of 12 chromosomes except chromosome 8, with contributions from 3.19%-26.23%. These digenic epistatic loci were located on all of the 12 chromosomes, with contributions ranging from 2.03%-8.93%. A QTL in marker interval R2510-RM211 on chromosome 2 affected both grain weight per panicle and the second leaf weight, which would be beneficial to super-high-yielding rice improvement.