Impact of Pinching, Cluster Thinning and Girdling on Productivity and Quality Attributes of Ruby Seedless Grapevines Grown at Warm Region

The experiment was executed over the consecutive seasons of 2020 and 2021 on the grape cultivar Ruby Seedless growing at the experimental orchard of Assiut University, Faculty of Agriculture. Thirty vines planted in clay soil were selected for this study. The selected vines were at the same vigour and age and at the beginning of the experiment and obtained the same horticultural practices. The selected vines were subjected to the following treatments: (Five vines/treatment), Pinching of the new shoots, Cluster thinning of the second cluster, girdling the arms, Pinching + Cluster thinning of the second cluster. Pinching + Thinning of the second cluster + Girdling the arms and Control. Total yield weight, cluster measurements, berry attributes as well as the quality of grape berries were determined. The obtained results suggested that all the treatments and their combinations were effective in enhancing productivity and berry quality of Ruby Seedless grape cultivar.