Bruna Vilela Carvalho
Abstract:
The Brachiaria genus plays an important role, due to the use of low fertility soils, which made the cattle breeding possible in the Cerrados region. With the use of these weak soils, it has begun the most efficient management alternatives. Among the limitations in Cerrado soils, there is the high exchangeable Al3 + content along the profile, and the use of liming raises the pH with consequent neutralization of toxic aluminum. But limestone has limited mobility in the soil restricting root growth to the surface layers, so agricultural plaster has favored the neutralization of subsurface Al in addition to providing Ca and S at greater depths. Thus, the objective of this research was to evaluate the residual effect of plaster associated with phosphate fertilization on the development of brachiaria and soybean crops grown in succession. The experimental design was a randomized block design in a 5 x 3 factorial scheme with 4 replications. The first factor corresponded to the doses of plaster (0, 1, 2, 4 and 8 Mg ha-1) and the second factor corresponded to the phosphorus doses (0, 40 and 80 kg ha-1 of P2O5). The use of agricultural plaster provides improvements in forage quality by reducing dry matter content and increasing mineral content, the latter being associated with the 80 kg ha -1 dose of P2O5. In the absence of phosphate fertilization the plaster reduces the mass productivity of dried plants. The use of agricultural gypsum increases Ca, S and N leaf contents in soybean plants and reduces K and Mg. The changes in soybean nutrition provided by the use of gypsum were not enough to affect grain yield. The absence of phosphate fertilization for two consecutive harvests in soil with adequate P content provides reduction in soybean yield.
