In this study,a full-length cDNA of allene oxide synthase (AOS) gene (named as CrAOS,JQ364955) was cloned from Catharanthus roseus.The gene was 2 118 bp in size containing an open reading frame (1 638 bp) encoding 545 amino acids.Comparative and bioinformatic analysis revealed that the deduced protein of CrAOS was highly homologous to AOSs from other plant species.Southern blot analysis revealed that it was a low-copy gene.Real-time Quantitative PCR (qRT-PCR) analysis showed that CrAOS mRNA accumulated most abundantly in old leaves and least in young alabastrums.The qRT-PCR analysis revealed that wound,low temperature,methyl jasmonic acid,ethylene treatments significantly enhanced CrAOS transcript expression,and salicylic acid had no influence.