Abstract: Using PCR degenerate primers designed based on GenBank published the conserved protein sequences of eugenol synthase genes to amplify cDNA fragments by RT-PCR and RACE-PCR，a new eugenol synthase gene named RcEGS1 was cloned from the flower petal of Rosa chinensis‘Pallida’，
and its GenBank accession number is JQ522949. The full cDNA was 1 171 bp in length with an open reading frame（ORF）of 951 bp encoding a protein of 317 amino acids. Molecular weight and isoelectric point of the protein was 35.64 kD and 7.36，respectively. Amino acids homology analysis indicated that
the RcEGS1 and RhEGS1 proteins are 47.7% identical to each other，and had 70% and 59% homologies with CbEGS2 in Clarkia breweri and PhEGS1 in Petunia hybirida，respectively. The expression profile of RcEGS1 in different tissues and different developmental stages of rose flower was analyzed by quantitat Real-time PCR. The results showed that RcEGS1 expressed specifically in the flower petals and the sepals，and it had the highest transcript level in the petal. In additional，RcEGS1 was higher transcript level in the developmental blooming stage，and lower levels in that of bud and senescence stage.

Key words: rose, fragrance, RcEGS1, qRT-PCR