Utilization of Brachiarias in the Improvement of Physical and Chemical Attributes of a Yellow Oxisol

Abstract

The study evaluated the effect of the cultivation of five species of grasses of the genus Brachiaria (B. decumbens, B. ruziziensis, B. brizantha, B. humidicola and B. brizantha CV MG-5) in physical and chemical properties and in the formation and stabilization of aggregates of a Yellow Oxisol. The test with the grasses in the absence and presence of fertilization was conducted in the Chã de Jardim area, belonging to the Centro de Ciências Agrárias-UFPB, located in the county Areia-PB. The experimental design was in randomized blocks, with subdivided parcels, in factorial scheme 5 × 2 × 4, with four repetitions, being: five species of Grass (Braquiarias), two conditions of mineral fertilization with NPK (absence or presence) and four depths of soil samples collection (0-5, 5-10, 10-20, 20-30 cm), totaling 40 subplots of 5.0 × 5.0 m, with 3 repetitions, totaling 120 sampling points. The grasses favored the formation of aggregates and contributed to their stability. Brachiaria brizantha is the most suitable grass to raise the organic matter content of an Oxisol without mineral fertilization.