Polyploidy remodels fruit metabolism by modifying carbon source utilization and metabolic flux in Ponkan mandarin (Citrus reticulata Blanco)

•Autotetraploidization modifies both primary and secondary metabolism in Ponkan mandarin fruit.•Autotetraploidization reduces the transcription of citric acid transport-related and utilization-related genes in fruit.•Lower levels of flavonoid and carotenoid in 4x fruit relates to the decrease in transport and utilization of citric acid.