This experiment was carried out at the Experimental Orchard of Assiut University, Faculty of Agriculture during two successive seasons 2018 and 2019 on 13 years old grapevines of White Banaty (Thompson Seedless) grape cultivar. The experiment aimed to examine the effect of GA₃ at different concentration (10, 20, 40 ppm and 10 + 20 + 40 ppm) and caffeic acid as alternative, safety compound at different concentration (1, 2, 3 g / litter and 1 + 2 + 3 g/Litter) on yield and fruit quality of Thompson Seedless grape cultivar. The obtained results revealed that spraying the clusters with GA₃ at 10 + 20 + 40 ppm gave the highest values of yield components and increased total acidity % while it decreased fruit quality. On the other hand, spraying caffeic acid at 2 g/Litter at full bloom was effective in improving yield, bunch, berry weight and berry quality. This study concluded that the beneficial effects of spraying caffeic acid (CA) at 2 g/Litter at full bloom as a new alternative compound to improve yield and fruit quality of White Banaty (Thompson Seedless) grape cultivar.
This study concluded that the beneficial effects of spraying caffeic acid (CA) at 2 g/Litter at full bloom as a new alternative compound to improve yield and fruit quality of White Banaty (Thompson Seedless) grape cultivar.
Key words: GA3, Caffeic acid, Thompson Seedless (White Banaty), Grape vine.