AUTHOR=Koyama Renata , Roberto Sergio R. , de Souza Reginaldo T. , Borges Wellington F. S. , Anderson Mauri , Waterhouse Andrew L. , Cantu Dario , Fidelibus Matthew W. , Blanco-Ulate Barbara 

TITLE=Exogenous Abscisic Acid Promotes Anthocyanin Biosynthesis and Increased Expression of Flavonoid Synthesis Genes in Vitis vinifera × Vitis labrusca Table Grapes in a Subtropical Region

JOURNAL=Frontiers in Plant Science

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.00323

DOI=10.3389/fpls.2018.00323

ISSN=1664-462X

ABSTRACT=<p>Hybrid (<italic>Vitis vinifera</italic> ×<italic>Vitis labrusca</italic>) table grape cultivars grown in the subtropics often fail to accumulate sufficient anthocyanins to achieve good uniform berry color. Growers of <italic>V. vinifera</italic> table grapes in temperate regions generally use ethephon and, more recently, (<italic>S</italic>)-<italic>cis</italic>-abscisic acid (<italic>S</italic>-ABA) to overcome this problem. The objective of this study was to determine if <italic>S</italic>-ABA applications at different timings and concentrations have an effect on anthocyanin regulatory and biosynthetic genes, pigment accumulation, and berry color of the Selection 21 cultivar, a new <italic>V. vinifera</italic> ×<italic>V. labrusca</italic> hybrid seedless grape that presents lack of red color when grown in subtropical areas. Applications of <italic>S</italic>-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins and of the individual anthocyaninsanthocyanins: delphinidin-3-glucoside, cyanidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside in the berry skin and improved the color attributes of the berries. Treatment with two applications at 7 days after véraison (DAV) and 21 DAV of <italic>S</italic>-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins in the skin of berries and increased the gene expression of <italic>CHI</italic>, <italic>F3H</italic>, <italic>DFR</italic>, and <italic>UFGT</italic> and of the <italic>VvMYBA1</italic> and <italic>VvMYBA2</italic> transcription factors in the seedless grape cultivar.</p>