Multi-omics analysis reveals molecular and metabolic differences between cold-tolerant and cold-sensitive peach cultivars

Low temperature is the main abiotic stress affecting the growth and development of plants in the cold region of northwest China. Gansu local varieties are highly resistant, have been naturally selected for many years, and are suitable for planting in cold areas. In this study, one-year-old branches of the cold-resistant peach variety ‘Ding jiaba’ (DJB) and the conventional cultivar ‘Xia cui’(XC) in the dormant period were used as experimental materials. The physiological and biochemical indexes of these varieties, as well as their transcriptome, proteome, and metabolome, were comprehensively analyzed. Physiological analysis showed that the antioxidant enzyme activity of 1-year-old DJB branches was higher than that of XC under low temperature across different dormancy periods. Analyses of transcriptomics, proteomics, and metabonomics revealed key pathways in peach responding to low-temperature stress. Functional enrichment analysis showed that pathways related to starch, sucrose metabolism, and flavonoid biosynthesis were significantly enriched during dormancy, suggesting that these pathways are important for peach to cope with low-temperature stress during dormancy. Candidate genes, such as SUS, CHS, CHI, and BMY, may regulate the response of peach to low-temperature stress. Overall, these findings help clarify the molecular mechanism of cold resistance in peach and provide new insights into the regulatory network of the low-temperature stress response during peach dormancy.