Soil green manure and physic-hydric attributes under rubber tree plantation in So Paulos western plateau, Brazil

Abstract

São Paulo's western plateau is a privileged region for rubber tree plantation, since it does not present favourable conditions for the development of plant disease. However, the soil in that region is still scarcely studied. This study has the objective of evaluating the effect of management practices applied between the lines of rubber trees (Hevea brasiliensis) in physic-hydric attributes of a red oxisol and redyellow ultisol, in the city of Jaboticabal-SP, in random blocks with four repetitions. The following treatments were applied between the lines: harrowing, green manure application with Pueraria phaseoloides and trimmer. The quantified data were: soil permeability, clay content, disperse clay, flocculation degree, water retention curve and total porosity, for four soil layers (0-0.10; 0.10-0.20; 0.20-0.30; and 0.30-0.40 m). The studied soils presented differences regarding water permeability for the different treatments. Higher gravimetric humidity for lower tensions in both soils was observed. Green manure with pueraria favors increase in total porosity in the studied soils, contributing for increase in total porosity, humidity and permeability.