Characterisation of the volatile compounds in nine varieties and three breeding selections of celery using GC-IMS and GC-MS

Celery (Apium graveolens L.) is a popular vegetable crop planted worldwide. In this study, the volatile compound characteristics of three A. graveolens var. dulce varieties (type D), and six A. graveolens var. secalinum varieties (type S), and three breeding selections were analysed and 41 and 73 volatile compounds were identified using GC-MS and GC-IMS, respectively. The results showed that type S emitted more terpenes and phthalides than type D varieties. Both GC-MS and GC-IMS could discriminate between type S and type D. Six potential biomarkers, i.e., sabinene, (E)-caryophyllene, α-phellandrene, limonene, γ-terpinene, and hexanal, were identified using both models. Both GC-MS and GC-IMS could discriminate between parent and breeding selection. The relative contents of seven (GC-IMS OPLS-DA model) and ten (GC-MS OPLS-DA model) volatile compounds showed over-parent heterosis. This study provides a technical reference for distinguishing celery varieties in the same habitat and preliminarily reveals the aroma relationship between breeding selections and their parents.