The study presents the analysis of the influence of summer pruning operations (defoliation, cluster thinning) on the parameters of a potential productivity of winter buds at the vine variety Vranec grown near Veles in the period 2013-2015. For this research, four treatments were set: control, defoliation and two types of cluster thinning: 10 and 6 clusters per vine. From the obtained results it is found that there are no injuries in the main winter buds during the vegetation period and the potential fruitfulness is determined by higher coefficient, 1.38, which depends on the location along the cane. The yield at this variety will be formed mainly by clusters with size of 350-550 μm, followed by those with the length of 550-750 μm. The application of defoliation and regulation of the vine yield has a beneficial effect on increasing the rate of potential fruitfulness of winter buds, the number of buds with 2 and 3 clusters, increasing the inflorescences with a length of 350-550 μm and the appearance of those longer than 750 μm.
