SUMMARY
The stressful climatic conditions of the last years have led to the need to pay more attention to the native varieties, which are adapted to the local conditions and ensure the obtaining of quality harvests. Autochthonous varieties of table grapes have dietary properties, attractive exterior appearance and excellent taste qualities.This work presents a 3-year study of the variability of grape composition of Codreanca (Black Magic) – a Moldavian grape variety, in a vineyard located in Purcari (Republic of Moldova). Grapevine were different pruned according to growth vigor: low - 18 – 22 buds (1 spur and 2 canes); medium vigor – 24 - 28 buds (1 spur and 3 canes) and high vigor – 30 - 34 buds (2 spurs and 4 canes). Climatic conditions and growth vigor had an important influence on vine fertility and productivity. Results showed that vine balance at which vegetative and reproductive growth can be sustained with adequate fruit production and desired fruit quality was found to be for Codreanca on vines with medium vigor. Grapes harvested from medium vigor vine recorded optimum values of quality (sugar and acid content, sugar/acid ratio) and cluster indexes (average weight, lenght and width, berry lenght and width, berry weight, grape and berry composition, cluster structure index, berry index, berry composition index, berry sfericity and cluster compactness). Viticultural practices used by grape growers can also increase or decrease vine growth as needed, to obtain high quality production.