Abstract: To enrich Osmanthus fragrans transcriptome data and clarify the difference of Osmanthus fragrans essential oil biosynthesis,three kinds of Osmanthus cultivars were selected and sequenced by Illumina Hiseq2000.RNA-Seq generated 14.4 G raw data,which was the de novo assembled into 70,029 Unigenes with a mean length of 762 nt,N50 of 1183 nt.Using pathway mapping and expression profiles,the different expressed genes (DEGS) were mapped to diterpenoid biosynthesis,terpenoid backbone biosynthesis,monoterpenoid biosynthesis,sesquiterpenoid and triterpenoid biosynthesis,phenylpropanoid biosynthesis,phenylalanine metabolism,alpha-linolenic acid metabolism,linoleic acid metabolism pathway.Among them,phenylpropanoid biosynthesis,phenylalanine metabolism,diterpenoid biosynthesis and terpenoid backbone biosynthesis pathway were significant difference in three samples,and total 650 DEGS were found in the four pathways which were encoding 54 enzymes.Mass sequence data of O.fragrans was obtained from Osmanthus cultivars of ‘Jinqiugui’,‘Baijie’ and ‘Rixianggui’.Using transcriptome analysis,the pathways of the different of essential oil components were revealed and the DEGS for changes in components of Osmanthus fragrans were examined preliminarily.Data presented in this study will provide reference for the metabolic regulation and expression in vivo of O.fragrans.

Key words: Osmanthus fragrans, biosynthesis of essential oil, transcriptome analysis, RNA-seq