The study of root distribution in soils is an adequate method to detect adverse conditions to root development, and evaluate the effect of soil alterations caused by soil management systems. With these objectives, a field experiment was carried out for five years on a Paleudult soil with oat + clover/maize under conventional tillage, reduced tillage and no tillage. To observe the structural modifications of the soil, an adaptation of the "profil cultural" method, was used along with the determination of bulk density, total porosity, macro and microporosity and penetrometer resistance of the soil. The rooting profile and the nailboard methods were used to determine root distribution and morphology. It was observed in the structural maps described that the treatment arrangements partially explained the presence of the roots in the profile. In the 10-15 cm and 25-35 cm layers, the plants growing under no tillage showed roots with radius greater than those under conventional tillage. The density (cm cm-3 ) was greater at the surface (0-5 cm) and smaller in the 10-15 cm layer. The soil tillage systems did not affect dry mass of the roots nor the yield of maize.
root; soil tillage; direct drilling; “profil cultural”