Effect of Soil Preparation and Layers on the Weighted Mean Diameter and Geometric Mean Diameter of a Red Distroferric Latosol

The objective of this work was to study the influence of three management systems on the physical attributes and productivity of irrigated wheat, cultivar BRS-254, in the city of Tangara da Serra, MT. The soil physical attributes were: weighted mean diameter (DMP) and geometric mean diameter (DMG). The experimental design was in randomized blocks. The treatments for weighted average diameter (WMD) and geometric mean diameter (DMG) were arranged in a subdivided plot scheme, with eight replications. The tilting preparations obtained the highest DMPs compared to SD both in the 0-10 cm layer and in the 10-20 cm layer, a result possibly related to the incorporation of residues during the soil preparation associated with higher mucilage production promoted by higher activity of the root system of the crop, which found better soil physical conditions for its development. The PC presented a reduction in DMP when comparing the value in the 0-10 cm layer with the value in the 10-20 cm layer. The significant effect of soil preparation on DMG can also be a result of the incorporation of residues during the preparation, associated to the effect of higher root volume promoted by the higher root growth of the crop in these preparations, which, in turn, guarantee greater production of mucilages promoting greater soil aggregation and higher DMG. The use of the disk grid in the PC and PM interferes with the soil attributes. Soil inversion provided higher WMD and DMG.