title: Whole transcriptome sequencing of nine  tree peony petals
design: For the tree peony variety 'Yu Hou Feng Guang' (S1, S2, S3), the petal spot parts were removed in three periods, and the remaining parts were grouped into YP1 (YP1_1, YP1_2, YP1_3), YP2 (YP2_1, YP2_2, YP2_3), and YP3 (YP3_1, YP3_2, YP3_3). Through differential analysis of flower color formation in these three periods, the corresponding key genes were identified.