show Abstracthide AbstractUsing genome-wide pattern analysis and quantitative-trait-locus (QTL) mapping, we identified that a natural allele of BrJMJ18, BrJMJ18Par, encoding a novel H3K36me3/2 Jumonji demethylase, confers thermotolerance by delayed flowering and stimulated vegetative growth on B. rapa.To assess the downstream genes of BrJMJ18, we conducted a chromatin immunoprecipitation (ChIP) seq experiment using a polyclonal antibody recognizing BrJMJ18 in Par plants under normal conditon (LD, 21?) and high temperature condiation (LD, 28?), respectively. Overall design: Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) for BrJMJ18-GFP in BrJMJ18 overexpresing Par plants. Par plants overexpressing tow allels of BrJMJ18, BrJMJ18WT (H1) and BrJMJ18Par (H2) were grown under low temperature (L, 21?) for 5 weeks or low temperature (L, 21?) for 4 weeks following with 1 week under high temperature (H, 28?), respectively. And wildtype Par plant was used as control (CK). The young and health leaves were collected for ChIP-seq. Two biological replicates were performed for each sample.