Abstract: The SrPDS gene cDNA sequence involved in carotenoids synthesis was cloned from the
yellow sepals of Strelitzia reginae Banks using RT-PCR and RACE techniques. The cDNA sequence
consists of 2 069 bp with an intact open reading frame of 1 746 bp，encoding a polypeptide of 581 amino
acids. Homology analysis showed that the deduced SrPDS protein was highly homologous to other PDS
proteins from different plants. Phylogenetic analysis indicated that SrPDS was clustered together with PDS
of Crocus sativus firstly and was more related to PDS of Narcissus tazetta and Lilium hybrid division. The
semi-quantitative PCR analysis indicated that SrPDS showed the highest transcript abundance in early
flowering season and SrPDS was highly expressed in leaves and yellow sepals，but lowly expressed in blue
petals and root. The results indicated that SrPDS played an important role in the growth of yellow sepals.

Key words: Strelitzia reginae Banks, phytoene desaturase, carotenoids synthesis, gene cloning