Comparative Evaluation of Routine Quality Traits, Primary Metabolites, and TD-GC-MS Volatile Profiles for Cultivar Discrimination in Newly Bred Peach (Prunus persica L.)

Three newly bred peach (Prunus persica L.) cultivars, 'Hwanggwibi', 'Seola', and 'Yanghongjang', were characterized using their routine fruit-quality traits and by means of primary metabolite profiling and thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS)-based volatile organic compound (VOC) profiling.The cultivars differed in terms of their fruit appearance, fruit weight, titratable acidity (TA), SSC/TA ratio, peel color, and firmness, although the soluble solids content (SSC) remained within a narrow range of 12.1-12.6°Brix.Primary metabolite profiling revealed cultivar-associated differences in sugars, sugar alcohols, organic acids, and amino acids, indicating that similar SSC values did not necessarily reflect similar metabolite compositions.The TD-GC-MS-based VOC profiles also differed among the tested cultivars.Among the VOCs confirmed using authentic standards, D-limonene, 2-ethyl-1-hexanol, and acetic acid showed cultivar-associated accumulation patterns.A dataset-level comparison showed significant cultivar-associated separation for routine quality traits, primary metabolites, TD-GC-MS-based VOCs, and the combined quality + VOC dataset.Cross-validated PLS-DA indicated high predictive ability for the TD-GC-MS-based VOC and combined quality + VOC datasets, with the combined dataset showing the highest Q 2 value.Because the fruits were obtained from distribution centers and evaluated within a single production season, the results should be interpreted as exploratory baseline information for this sample set rather than as validated genotype-level markers.These results indicate that TD-GC-MS-based VOC profiling can complement conventional fruit-quality measurements for characterizing newly bred peach cultivars.