Abstract
This study aimed to evaluate the effect of different rates and times of application of Abscisic Acid (ABA) and Ethephon on color properties and quality of Crimson Seedless grapes grown in the São Francisco River Valley, Brazil. The experiment was carried out over three growing seasons in a commercial vineyard in Petrolina, Pernambuco State, Brazil. The treatments consisted of control, Ethephon, and Abscisic Acid (ABA) applied at 400 mg/L and 600 mg/L. ABA rates were tested in four different ways: a single application at veraison from 90 to 97 days after pruning (DAP); two applications of half the application rate, the first one at veraison or berry softening (90 to 97 DAP) and the second at 17 to 20 days postveraison (DPV); single application at 17 to 20 DPV; and ABA at 200 or 300 mg/L combined with Ethephon. There was no influence of ABA and Ethephon on yield, cluster weight, berry diameter, skin elasticity, soluble solids and sugar content, whereas titratable acidity was influenced only in the first cycle. Flesh firmness was differentiated by higher rates of ABA and when associated with Ethephon, in the third cycle. When Ethephon was associated with ABA 300 mg/L at veraison (97 DAP) in 2012, the berry showed darker skin color, lower lightness (L*) and a higher b* value, indicating more advanced maturation. The anthocyanin content increased in response to ABA and Ethephon in the three cycles studied, resulting in darker berries red color; however, the extent of responses varied among production cycles.
- ©2014 by the American Society for Enology and Viticulture