C. Burlacu and S.P. BarbuThe importance of the technology in vine planting material production, the efficiency in the grafting process, and the quality of the resulted material are becoming interesting objectives in the field of viticultural research in Romania. The modern technologies are trying to be based more on mechanical grafting and less on human manual labor due to aspects regarding the cost and time pressure. In the current study was approached the importance of the biological compatibility between rootstock and scion in the grafting process. The grafting technique used was mechanical grafting in the omega section. Four well known grapevine cultivars, 'Afuz Ali', 'Italia', 'Merlot', and 'Fetească albă' and three from the most utilized rootstocks in the Valea Calugareasca viticultural center were selected for the grafting process. Various aspects such as the efficiency of the grafting process and the development of the grafted vine shoots and roots were evaluated. The study revealed better compatibility of the grafting process between 'Afuz Ali', 'Merlot', and 'Fetească albǎ' with the 'Berlandieri' x 'Riparia Kober 5BB' rootstock and between 'Italia' with 'Berlandieri' x 'Riparia Teleki 8B', 'Crăciunel 71' selection. Regarding the vine grafted development, the results did not highlight the influence of a particular rootstock, so the 'Berlandieri' x 'Riparia Kober 5BB' had the most significative influence on the 'Feteascã albǎ' development, but 'Berlandieri x Riparia Teleky 4B SO4-4' rootstock was the most reliable in all the four combinations.