The present study aims to determine the optimal nitrogen dose that preserves soil mineralization properties. The evaluation managed for ammonium (NH4+), nitrate (NO3-) and mineral nitrogen (N min) concentrations under no-tillage (NT) and conventional tillage (CT) systems. The experiment was monitored in the greenhouse of the National Institute of Agricultural Research (INRA) in Rabat, Morocco, using a vertisol soil type from Marchouch INRA station. The Analysis of Variance (ANOVA) revealed a highly significant effect of sampling stage (stages 1,2,3 and 4; p < 0.001), and significant effects of nitrogen dose (0,50,100, and 150 kg/ha; p <0.05) and tillage system (CT vs NT; p < 0.05). Several significant interactions between these factors were considered. NH4+ concentrations were influenced by, Stage × Tillage system × Depth, Stage × Tillage system, and Stage × Dose interactions (p < 0.05). For NO3-, a significant Stage × Dose interaction was detected (p < 0.05), while for N min, a significant Tillage system × Dose interaction was found (p < 0.05). The recommended optimal dose is 50 kg/ha, which demonstrated a nitrogen mineralization efficiency of 63% at the 0-10 cm depth and 40 % at the 10 – 20 cm depth under NT. Nitrogen doses exceeding 100 kg/ha resulted in substantial N min losses under both tillage systems. These results provide new patterns into the nitrogen dose-tillage systems interaction in vertisol soils, offering the first experimental quantification of N mineralization efficiency across wheat growth stages in Marchouch, Morocco.