Abstract: In order to reveal the mechanism of the BrFLC5 gene in the process of flowering time，we cloned exon2–exon4 of BrFLC5 in twelve Brassica rapa accessions with a wide range of flowering time variation. There was a single-base mutation（G–A）in the Pi3 + 1 of BrFLC5 exon3 and subsequently a dCAPs marker for BrFLC5 was developed in the B. rapa. We screened 93 accessions from ten different cultivar groups and analysed the correlation between flowering time and dCAPs marker for BrFLC5. The results showed that the flowering time was significantly correlated to the dCAPs of BrFLC5（P < 0.05）. The special marker can be easily used for marker-assisted selection（MAS）of the bolting and flowering time in breeding.

Key words: Brassica rapa, bolting and flowering time, BrFLC5, dCAPs marker