Changes in the abscisic acid, phenylpropanoids and ascorbic acid metabolism during strawberry fruit growth and ripening.

The functional compounds and sensory attributes of strawberries are acquired during ripening; however, the molecular mechanisms regulating this process have not yet been fully elucidated. Therefore, in this study, we aimed to investigate the accumulation of abscisic acid (ABA), phenylpropanoids, and l-ascorbic acid (AsA) as well as their relative gene expression levels during this process. The accumulation of ABA during the fruit growth and ripening stages depends on the upregulation of FaNCED1 and FaNCED2 gene expression, and the downregulation of FaCYP707 expression. Moreover, in the initial stages, the ABA glycosylation pathway is activated as a provision for the ABA levels required for future events. As the ABA levels increase, FaPAL, FaC4H1, and FaC4H4 genes expression are upregulated, aiding in the synthesis of flavonoid precursors, which, in addition to the higher FaUFGT expression, directly reflects an improvement in anthocyanin. AsA content increases during fruit development and ripening and is...