Transcriptomics combined with HS-SPME-GC/MS and IMS was used to investigate aroma compound formation in 'Fengtang' plum at different maturity stages.

This study analyzed the volatile components of 'Fengtang' plum at different maturity stages using GC-MS and GC-IMS, identifying 54 and 60 compounds respectively. Aldehydes and alcohols were the main volatiles, with key contributors such as ethyl acetate, 1-hexanol, methyl formate, heptanal, 1-penten-3-ol, and 1-pentanol influencing the fruit's sensory profile. A transcriptome database was built for key aroma development stages, and a flavor-related transcriptomic network was established using volatile compound data. Phenylpropanoid metabolism, amino acid metabolism, carbohydrate breakdown, and the tricarboxylic acid (TCA) cycle were found to contribute to precursor accumulation for volatile synthesis. Key enzyme-coding genes, including PAL, 4CL, CCR, ADH, F5H, COMT, CAMT, SPS, PK, TRP2, AST, and BCAT, were involved in this process. Based on Arabidopsis annotation and JASPAR prediction, 465 transcription factors were identified, mainly from the WRKY, DOF, TCP, AER, and ARF families, potentially regulating plum maturation. In conclusion, aldehydes and alcohols can serve as maturity markers to assess fruit ripeness.