2018 ASHS Annual Conference

We examined the effects of ABA or abscinazole (Abz) application, which is ABA 8’-hydroxylase inhibitor, on anthocyanin and sugar biosyntheses in ‘Kyoho’ (Vitis labrusca × V. vinifera) grapes. Three groups were created in this study. ABA (first group) was applied to grapevines and Abz (second group) was applied to grapevines at véraison and 7 days after véraison. The third group was the untreated control. Grape berry skin was sampled at 15, 30, 45, 60 days after treatment (DAT). The anthocyanin and glucose, fructose, and sucrose concentration, anthocyanin biosynthetic genes, and sucrose transporter gene expression levels were analyzed. ABA application significantly increased anthocyanin concentrations but Abz application increased those concentrations significantly only at 15 DAT. Abz application increased glucose, fructose, and sucrose concentrations in the skin higher than the untreated control and ABA treated group. Moreover, Abz application up-regulated VvSUT expression levels. From these results, ABA application may induce anthocyanin accumulation in ‘Kyoho’ grape berries, and Abz application may enhance sucrose transportation and increase sugar concentrations.