Abstract
This study performed physiological, transcriptome, and metabolite analyses of peach fruit under different nitrogen (N) conditions at different growth stages. Nitrogen management directly affected the yield, fruit quality, and metabolites of peach in different growth stages. Different fertilizing time influenced yield and leaf N concentration. RNA-Seq was used to analyze the influence of N levels at the fruit pit hardening (PH) and fruit expansion (FE) stages. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed differentially expressed genes (DEGs) related to carbon and nitrogen metabolite processes. Metabolome analysis shows that applying different nitrogen fertilizers at different growth stages of peach mainly affected metabolites related to carbon and amino acids. This research provides insight into the metabolic processes underlying different N responses during different growth stages and provides a foundation to improve the efficiency of N use in peach.