controls kernel size and plant architecture in rice.

Kernel size and plant architecture play important roles in kernel yield in rice. Cloning and functional study of genes related to kernel size and plant architecture are of great significance for breeding high-yield rice. Using the single-segment substitution lines which developed with as a donor parent and an elite cultivar Huajingxian74 (HJX74) as a recipient parent, we identified a novel QTL (quantitative trait locus), named , which controls kernel size and plant architecture. Compared with HJX74, the kernel length, kernel width, 1000-kernel weight, panicle length, kernels per plant, primary branches, yield per plant, and plant height of near isogenic line- (NIL-) are increased, whereas the panicles per plant and secondary branches per panicle of NIL- are comparable to those of HJX74. was narrowed to a 239.18 kb interval on chromosome 3. Cell analysis showed that NIL- controlled kernel size by regulating cell growth. controls kernel size at least in part through regulating the transcription levels of , , , , , and . These results indicate that might be beneficial for improving kernel yield and plant architecture in rice breeding.