Objective  To explore the mechanism of synthesis and metabolism of terpenoids released by plants, and to provide theoretical basis for further elucidating the biological functions of the terpenoid synthase gene family in tree peony.

Method  Based on the aromatic tree peony variety ‘High Noon’, the PsGES gene was cloned based on transcriptome sequencing of the obtained fragments. Simultaneously, the PsGES gene overexpression vector was injected into tobacco leaves and ‘Fengdan’ petals using transient expression methods to verify gene function.

Result The complete CDS sequence of this structural gene was 897 bp long, encoding 298 amino acids. Amino acid sequence analysis showed that the protein had high conservation, with a conserved domain Terpene_ Cyclase_ Plant_ C1. The expression level of PsGES gene was highest in the blooming petals and significantly higher than other organs. Subcellular localization analysis showed that PsGES was mainly localized in chloroplasts. The release of geraniol in tobacco leaves and ‘Fengdan’ petals could be detected by GC-MS method, while the PsGES gene was highly expressed in tobacco leaves and ‘Fengdan’ petals.

Conclusion This study indicates that the PsGES gene regulates the synthesis of geraniol in plants.