1-MCP delays ripening and maintains postharvest quality of nectarines by regulating transcriptional and metabolic responses

Fast ripening and senescence is one of the major problems for postharvest nectarines, leading to a rapid decline in postharvest quality. As an ethylene-action inhibitor, 1-methylcyclopropene (1-MCP) was applied to treat nectarines with a concentration of 1 μL L−1 for 18 h and stored at 0 °C for 25 d. The postharvest physiological quality attributes including the flesh color, total soluble solids (TSS), titratable acid (TA), and aroma quality of fruit flesh from different positions (top, equatorial, and bottom of nectarine fruit) were evaluated to elucidate that 1-MCP differentially influence the flesh ripening and biological metabolism. The findings indicated that 1-MCP treatment effectively delayed ripening and senescence processes. Moreover, the cellular microstructure and intracellular organelles were observed which suggested that 1-MCP delayed the deformation of the cellular microstructure and maintained its integrity. Furthermore, transcriptomic and metabolomic analyses explored the differential metabolites and their biological features. The differential metabolites after 1-MCP treatment were related to signal transduction, membrane transport, genetic translation, and metabolism pathways. The KEGG enrichment results showed that the most impacted pathways by 1-MCP include glycolysis and gluconeogenesis.