Use of carbon dioxide-controlled atmospheres (CA) has proven to be effective for the preservation of cut flower storage. In this study, the preservation mechanism of CO₂-based CA for cut peony storage was systematically evaluated using quality trait analysis, physiological detection, and metabolomic profiling. ‘Qihua Lushuang’ was selected as the model cultivar to screen optimal gas compositions, with additional validation on three commercial varieties (‘Red Charm’, ‘Lian Tai’, ‘Lu Xihong’). Cut peonies were stored at 2 °C for up to 60 d, and the effects of different gas components, regulation methods (artificial CA vs. spontaneous modified atmosphere, MA), and variety-specific responses were analyzed. Metabolomic analysis via LC-MS/MS was performed on samples from 0 d (control), non-modified atmosphere (CK), and CA treatments to identify differential metabolites and enriched pathways. The results showed that the gas composition of 5% O₂ + 20% CO₂ + 75% N₂ achieved the best preservation effect. Metabolomic analysis identified 58 metabolites, which were enriched in carbon metabolism, biosynthesis of secondary metabolites, and cyanamino acid metabolism pathways. These metabolic changes collectively contributed to delayed senescence by preserving carbon metabolic activity, and maintaining energy homeostasis. The CO₂-enriched CA treatment (5% O₂ + 20% CO₂ + 75% N₂) effectively prolongs the postharvest longevity of cut peonies through multi-dimensional regulation of physiological and metabolic processes. This study provides a practical and universally applicable preservation technology for cut peonies, while shedding light on the underlying metabolic mechanisms of CA storage, which is valuable for the sustainable development of the cut peony industry.
Wáng et al. (Fri,) studied this question.