In this work, we studied agro-morphological parameters that could be used to define variaton among early, mid-early, mid-late and late potato cultivars, cropped in the main season by quantitaive and qualitative parameters (characters of mother tubers, vegetation cover, height of plants, number of leaves, number of true leaves, number of stems, number of stolons, lenght of first stolon, median diameter of first stolon, caliber of first tuber, final number of tubers per plant and final yield per plant). For the main agro-morphological characters, there were a great variation compared to the control Spunta. Challenger and Fabula showed the heighest caliber of mother tubers (49.16 mm), while heighest weight of seed tubers was determined on cv. Alegria (125.7 g). Among other characters, challenger produced the largest leaf area (9940.3 mm²). Panamera cultivar has considerable plant height (13.77 cm), the heighest number of leaves per plant (63.33) and also the heighest number of true leaves (48.48). Moreover, Panamera has the largest lenght of first stolon with 8.66 cm, (6.16 cm for Spunta). It has also the largest value of median diameter of first stolon with 2.17 mm and followed by Mondial (2.23 mm), Bellini (1.63 mm) and Liseta (2.01 mm). The difference among the cultivars in terms of median diameter of first stolon was statistically significant (P≤0.05). Liseta has the largest value of caliber of first tuber (37.4 mm), followed by Bellini (37.71 mm), while, Spunta has presented the lowest measures (13.36 mm). For final yield per plant, Bellini outyielded other cultivars with 0.96 kg per plant.
