Effect of Different Levels of Cluster Tipping On Quality Characteristics and Phenolic Composition in Crimson Seedless Grape Variety

Abstract

In table grapes, berry size, homogeneous colour, and medium-dense cluster structure are desirable characteristics. However, the Crimson Seedless grape variety has late maturity small berry size, and poor colour. The study aimed to apply different levels of technical applications to the vines to achieve the desired quality of this table grape variety and it was used completely randomized block design with three replicates for each treatment, and six vines in each replication. Treatments were made as control (C), 1/5 (A1), 1/3 (A2), and 1/2 (A3) cluster tipping (CT). As a result, the grape variety was affected by both vintage averages effect of different rates of CT applied in both years on some quality characteristics and the phenolic composition of the Crimson Seedless grape variety was found to be statistically significant (p<0.05). According to the findings, treatments A1 and A2 for CT were more efficient than the control in enhancing cluster features, berry diameter, and berry quality. Organic acids in both years, the highest values of tartaric acid and malic acid were found in the control and A1 treatments, while the lowest values were found in the A2 and A3 treatments. On the other hand, CT treatments increased as the average peonidin-3-glucoside by 48.58%, malvidin-3-glucoside by 20.54%, cyanidin-3-glucoside content by 15.98 %, delphinidin-3-glucoside by 7.85%, and petunidin-3-glucoside by 7.48 % in both years.