Epigenetic Regulation of Anthocyanin Accumulation in Horticultural Crops: Implications for Crop Quality, Postharvest Stability, and Prospective Functional Food Research

Anthocyanins, an important class of flavonoids, determine the color quality of many horticultural crops and influence their postharvest quality. Their accumulation is controlled by the phenylpropanoid–flavonoid biosynthetic pathway and by post-synthetic modifications such as glycosylation, acylation, and methylation, which contribute to pigment chemical diversity and stability. To better understand and control anthocyanin beyond conventional breeding, increasing evidence indicates that epigenetic mechanisms, including DNA methylation, histone modifications, noncoding RNAs, and chromatin remodeling, regulate anthocyanin biosynthetic and regulatory genes and thereby influence the accumulation of anthocyanins. This review examines anthocyanin biosynthesis and the epigenetic regulation of anthocyanin accumulation in horticultural crops and discusses prospects for targeted quality improvement. We distinguish plant-level epigenetic evidence from downstream evidence on anthocyanin composition, postharvest stability, and bioavailability and identify current gaps in linking epigenetic marks to functional outcomes.