Comparison of gene expression profile of flag leaf from fertile and sterile lines of rice

To examine the role of formation of a strong sink during leaf senescence, we compared the expression profile of the flag leaf of three different sterile mutant lines with fertile plants. The fertile and sterile lines showed basically similar expression profiles of flag leaves sampled at the same time. However, the fertile lines showed more rapid and enhanced change in transcriptome as compared to the sterile lines indicating that leaf senescence initiated independent of sink formation and is accelerated by sink formation. Three independent mutant lines, namely, pair1, pair2, and mel1-1, and fertile plants (homozygous or heterozygous) derived from each segregating population were used for comparison. The flag leaves were sampled at initiation of heading, 1 week after heading (WAH), 2 WAH, and 3 WAH, with three biological replicates.