design: Chromatin immunoprecipitation (ChIP) was performed on plant samples (three biological replicates) using antibodies against H3K4me3 (Abcam, ab8580), H3K27ac (Abcam, ab4729/ab177178), H3K9me3 (Active Motif, 39062) and H3K27me3 (Sigma-Aldrich, 07-449), sequencing libraries were prepared with the VAHTS Universal DNA Library Prep Kit for MGI (Vazyme, China, cat. no. NDM607), 200-500 bp library fragments were enriched and quantified, and reads were aligned to the B. carinata C4012 reference genome.