No-tillage (NT) is an agricultural practice recommended in context of conservation agriculture. The NT management is widely used under various cropping systems and could modify the physico-chemical and biological properties of the soil including phosphorus (P) stratification along soil profile. Consequently, root development and morphology of crops could be modified. The objective of this study was to investigate the effects of different tillage and P fertilization rates on corn (Zea mays, L.) root distribution and morphology. A field experiment was established in 1992 (Ziadi et al. 2014) on a clay loam soil in the L’Acadie research center of Agriculture and Agri-Food Canada. It is a completely randomized split-plot design (four replicates) in which main factor is soil tillage (moldboard plow (MP) and no-till (NT)) and sub-plot factor is P fertilization (0 (0P), 17.5 (1P) and 35 (2P) kg P ha-1 applied every two years). Soil is under a corn-soybean rotation. After 22 years of experimentation, soils and roots were sampled at silking stage by collecting 8-cm diameter soil cores to a depth of 40 cm at 5 cm, 15 cm and 25 cm perpendicularly to the corn row. Cores were then cut out at 0-5, 5-10, 10-20, 20-30 and 30-40 cm. After washing and sieving, root weight, length and surface area of primary (diameter >0.08 cm), secondary (0.02< diameter< 0.08 cm) and tertiary (diameter < 0.02 cm) roots were determined with the software WinRHIZO. After air-drying and sieving (<0.02mm), soil P status was assessed by soil solution phosphate ions concentration (Cp) in suspensions.Read less <