Effect of Abscisic Acid on Yield, Anthocyanins, Polyphenols and Procyanidins in Grape cv. Cabernet Franc (Vitis vinífera L.)

Aims: In recent years the wine industry in Mexico has increased its production as a result of exports and recognition for its wine quality abroad. An actual problem related to lack of berry pigmentation at harvest time was found in the cultivar Cabernet Franc. Its consequences involves in a delay on the biochemistry of maturity components and its impact in the wine elaboration. Abscisic acid (ABA) is a plant hormone involved in various stages of fruit maturity; however, little is known on its direct role in berry pigmentation and other fruit maturity components. On this basis and with the purpose to study the effect on yield, pigmentation and fruit quality, ABA was applied on the cv. Cabernet Franc.

Study Design: A completely randomized block design was used with four replicates per treatment. The data were analysed with the statistical program 'RStudio’ for Windows version 10. , The Tukey (P < 0.05) test was applied for the analysis of variance and comparison of means.

Place and Duration of Study: The experiment was conducted at the vineyard San Lorenzo, Casa Madero in Parras de la Fuente, Coahuila, Mexico and Horticulture lab in Universidad Autónoma Agraria Antonio Narro in Saltillo, Coahuila, Mexico, during the period of June - December 2017.

Methodology: When berries on rachis reached the veraison stage, a first spray of ABA was applied on the bunches using a 10 L back sprayer. The treatments were Control (H2O); 200, 400, 600 and 800 mg L-1 of ABA. The second spray at same doses was applied 14 days after first application.

Results: It was observed that ABA at any doses did not affect the weight, length, pH, soluble solids and acidity in fruits nor in yield. ABA at any concentration provoked a significant increment in the levels of anthocyanins, polyphenols and procyanidins in the harvested fruits.

Conclusion: It can be concluded that ABA as a hormone treatment can be used at the veraison stage in Cabernet Franc to improve the contents of anthocyanins, polyphenols and procyanidins in berries.