4 results

Soil phosphorus availability and soybean response to phosphorus starter fertilizer

Ciro Antonio Rosolem, Alexandre Merlin

01/Oct/2014

Phosphorus fixation in tropical soils may decrease under no-till. In this case, P fertilizer could be surface-spread, which would improve farm operations by decreasing the time spend in reloading the planter with fertilizers. In the long term, less soluble P sources could be viable. In this experiment, the effect of surface-broadcast P fertilization with both soluble and reactive phosphates on soil P forms and availability to soybean was studied with or without fertilization with soluble P in the planting furrow […]

Macronutrient accumulation and decomposition of brachiaria species as a function of nitrogen fertilization during and after intercropping with corn

Nídia Raquel Costa, Marcelo Andreotti, Salatiér Buzetti, Keny Samejima Mascarenhas Lopes, Fernanda Garcia dos Santos, Cristiano Magalhães Pariz

01/Aug/2014

In regions with a tropical climate, the greatest limitations for straw maintenance on the soil surface are difficulties on its establishment and high rates of decomposition. With the aim of identifying the productive potential of Xaraes and Ruziziensis grasses, as well as subsequent straw formation for continuity of the no-tillage system, the following factors were evaluated: the dry matter yield, the lignin/total N ratio, macronutrient accumulation, and straw decomposition in two growing seasons. The treatments consisted of two Brachiaria species […]

Soil nitrogen dynamics after Brachiaria desiccation

Gustavo Castoldi, Jhônatas Gomes dos Reis, Laércio Augusto Pivetta, Ciro Antonio Rosolem

01/Dec/2013

Brachiaria species, particularly B. humidicola, can synthesize and release compounds from their roots that inhibit nitrification, which can lead to changes in soil nitrogen (N) dynamics, mainly in N-poor soils. This may be important in crop-livestock integration systems, where brachiarias are grown together with or in rotation with grain crops. The objective of the present study was to determine whether this holds true in N-rich environments and if other Brachiaria species have the same effect. The soil N dynamics were […]

Potassium supply as affected by residual potassium fertilization in a Cerrado Oxisol

Ciro Antonio Rosolem, João Paulo Testa Moura Montans Vicentini, Fábio Steiner

01/Nov/2012

In some soils with low levels of exchangeable potassium, non-exchangeable forms can participate in plant supply. There is evidence that K supply in non-exchangeable forms depends more on plant nutrient demand than on soil properties. The purpose of this study was to evaluate the supply and depletion of K forms in a Cerrado Oxisol, as affected by residual K fertilization and successive cultivation of Brachiaria ruziziensis (Syn. Urochloa ruziziensis). Soil samples were collected in the 0-20 cm layer in plots […]