Transcriptome sequencing of manganese sulfate -treated berry skins of Vitis vinifera cv. Cabernet Sauvignon

Flavonoids are vital for developing the quality of grape and wine, and manganese deficiency decrease grape flavonoids accumulation and berry coloration. However, the effects of manganese sulfate on grape metabolic profiles have not been well studied and the underlying mechanisms are poorly understood. In this study, three different concentration of manganese sulfate were applied to Cabernet Sauvignon (Vitis vinifera L.) exploring their effects on berry composition. Results demonstrated that high concentration manganese application effectively improved grape organs manganese concentrations in and leaf photosynthesis. Malvidin-acetyl-glucoside, malvidin-glucoside, malvidin-trans-coumaroyl-glucoside, and peonidin-acetyl-glucoside concentrations were significantly increased under H treatment during grape development. Transcriptome and weighted gene co-expression network analysis jointly revealed that structural genes (VvDFR and VvUFGT) of flavonoid biosynthesis and carbohydrate metabolism pathway in red module were upregulated by H treatment, and were significantly positively correlated with malvidin- and peonidin- derived anthocyanins. Overall, this study suggests that soil manganese application trends to regulating berry transcriptional and metabolic profiles, and promote flavonoid accumulation, which provides novel insights for improving manganese fertilizer management in viticulture.