Relationship Between Color Development and Anthocyanin Metabolism in Table Grape (Vitis vinifera L.) cv. Crimson Seedless Applied with Abscisic Acid and Sucrose during Berry Development

Crimson Seedless is one of the most important table grape varieties in Chile, but under certain environmental conditions, there is not an adequate red color development causing economic losses due to a lower quality. The use of plant growth regulators during development, such as abscisic acid (ABA) and ethylene, increases the anthocyanin content of the skin improving the color of the berry. Recently, sucrose has been identified as a signaling molecule capable of regulating the expression of genes of the anthocyanin synthesis pathway. The aim of this study was to analyze the effect of the application of ABA and/or sucrose on color development and their relationship with the anthocyanin metabolism. Applications of ABA (400 ppm or 200 ppm) and sucrose (90mM) were performed close to verasion stage. During development and at harvest quality attributes such as berry firmness, total soluble solids and titratable acidity were not affected by the treatments. The red color development in the bunches was promoted in the fruit applied with either ABA or sucrose due to an accumulation of anthocyanins. Sucrose treatment showed higher levels of anthocyanins than the control treatment, but lowers than the treatment with ABA. In regards to the genes involved in the anthocyanin synthesis pathway, an increased expression in the ABA and sucrose treatments was observed compared to the control treatment. Therefore, based on these findings we demonstrated that sucrose would improve the color development by increasing the synthesis and accumulation of anthocyanins; thus, inducing earlier harvests and improving table grape quality.