Effect of Foliar Application of Gibberellic acid, Salicylic acid and Ammonium nitrate on Berry Quality of Ruby Seedless Grape Cultivar

Abstract

Experiment was carried out throughout two successive seasons of 2020 and 2021 on Ruby Seedless grapevines grown at the Experimental Orchard of Assiut University, Faculty of Agriculture. The study was performed to evaluate the influence of Gibberellic acid (GA3), Salicylic acid and Ammonium nitrate on berry quality of Ruby Seedless grape cultivar during 2020 and 2021 seasons. Data revealed that, the application of Salicylic acid (SA) and Ammonium nitrate increased TSS% while GA3 reduced it compared with the control. All treatments decreased TA% except SA in the 1 st season increased it. In 1 st season although there was an increase in reducing sugars due to different treatments comparing with the control, the differences were not significant in most of the treatments. The significant effect was only found in the NH4NO3, while during 2 nd season significantly increased it with an exception of (SA+GA3). SA gave the highest values for anthocyanins either in the 1 st season (61.85 mg/100gm) or two seasons average all the treatments (43.44 mg/100gm).