The purpose of the investigation was to determine the use of water in grafted vines (Vitis vinifera L.) in dependence on the vine (Vitis sp.) rootstocks. The local vine variety 'Rebula' was grafted on three different rootstocks (Vitis sp.): (1) on the 'Rebula' (Vitis vinifera L.) vine itself, (2) on the rootstock 196/17 Castel' (Vitis vinifera 'Mourvedre' x Vitis rupestris '1202 Couderc') x Vitis riparia 'Gloire' and (3) on the rootstock 'Börner' (Vitis riparia x Vitis cinerea). Daily transpiration was calculated as a difference in the pot mass between the day of measurement and the previous day. Daily differences in the use of water were compared with leaf area and meteorological data (temperature, duration of sun light). Stem water potential (SWP) and, at the end of the trial, leaf area and mass of individual parts of plant (roots, shoot) were determined using destructive method. The dynamics of water used per leaf area unit showed the trend of reduction and the response to the changing meteorological conditions. No statistically significant differences in SWP, leaf area and water used were noticed between rootstocks, however, they existed in the final mass of shoot and roots. Namen raziskave je bil določiti porabo vode pri enoletnih cepljenkah vinske trte (Vitis vinifera L.) v odvisnosti od podlage vinske trte (Vitis sp.). Lokalno vinsko sorto 'Rebula' smo cepili na tri različne podlage: (1) na samo sebe, 'Rebula' (Vitis vinifera L.), (2) podlago '196/17 Castel' (Vitis vinifera 'Mourvedre' x Vitis rupestris '1202 Couderc') x Vitis riparia 'Gloire' in (3) podlago 'Börner' (Vitis riparia x Vitis cinerea). Dnevna transpiracija je bila izračunana kot razlika v masi lonca z rastlino, med dnevom merjenja in predhodnim dnevom. Dnevne razlike v porabi vode smo primerjali z listno povr_ino in meteorolo_kimi podatki (temperatura, sončno obsevanje). Določili smo vodni potencial stebla (SWP), na koncu poskusa pa, z destruktivno metodo, listno povr_ino in maso posameznih delov rastlin (korenine, poganjek). Dinamika porabe vode na enoto listne povr_ine je pokazala odziv na spremenljive meteorolo_ke razmere in trend zni_evanja. Med podlagami nismo opazili statistično značilnih razlik v vodnem potencialu stebla, listni povr_ini in porabi vode, statistično značilne razlike med podlagami so obstajale le v končni masi poganjka in korenin.