Abstract: Nine Brassica campestiris accessions with a wide range of flowering time variation were used for screening of sequence variation of BrFLC2. Using gene specific primer pair，a fragment about of 1 400 bp was generated from all accessions. Sequencing of fragments revealed there were fragment length differences among the nine accessions，and an insertion/deletion（InDel）marker was developed for BrFLC2 based on the sequence variation. We screened the flowering time and the genotype of 146 accessions from eight different cultivar groups and found that：The flowering time was significantly correlated to the genotype of In/Del genotype of BrFLC2（r = 0.412，P < 0.01）.The flowering time of Del genotype accessions（average at 71 days）were much earlier than the In genotype accessions（average at 109 days）. These results indicated that InDel marker was significantly correlated to the flowering time and can be easily used for marker-assisted selection（MAS）in breeding. 　

Key words: Brassica campestiris, flower, BrFLC2, InDel marker