Soil Penetration Resistance and Sugarcane Rooting Under Subsuperficial Drip Irrigation Levels

Abstract Knowledge of the soil water regime in a dynamic equilibrium condition (steady state) emitter–soil–plant system is essential to evaluate adopted irrigation management, aiming maximize use efficiency irrigation. Thus, our objective was determine integrated effect four levels on moisture (θ v ) distribution pattern, mechanical penetration resistance (PR), and sugarcane rooting. Irrigation were established based percentage reference evapotranspiration (ETo), as follows: 40% (W1), 70% (W2), 100% (W3), 130% (W4) ETo. From profile PR versus θ regression models, profiles for each level estimated. At end crop cycle, trenches opened assess root system. According results, resulted soil-wetting pattern that did not match rooting profile. For treatments W3 W4 wetting indicated loss through deep percolation. all considering entire profile, values ranged from < 2 10 MPa. Also, roots superficially spread limited first 0.35 m depth depths applied. Although by reduced strength cohesive layer, this reduction insufficient allow deepening plant roots. The su garcane development region defined value approximately equal 2.0