GS6.1 controls kernel size and plant architecture in rice

Abstract Kernel size and plant architecture are critical agronomic traits that greatly influence kernel yield in rice. We identified a novel quantitative trait locus (QTL), named GS6.1 , which regulates kernel size and plant architecture in rice. Near isogenic line- GS6.1 (NIL- GS6.1 ) produces long and narrow kernels by regulating cell length and width in the hull, thus increasing the 1000-kernel weight. Compared with the control, the plant height, panicles per plant, panicle length, kernels per plant, and secondary branches per panicle of NIL- GS6.1 are increased. In addition, GS6.1 regulates the kernel filling rate. GS6.1 controls kernel size at least in part through regulating the transcription levels of EXPA13 , EXPA19 , EXPB14 , GS2 , GS3 , GL3 , GL6 , OML4 , GL7 , and GL10 . These results indicate that GS6.1 might be beneficial for improving kernel yield and plant architecture in rice breeding by molecular design.