Soja de primeiro e segundo cultivo em solo arenoso após pastagem com aplicação de gesso e nitrogênio

Abstract

The growing demand for food coupled with the need for environmental preservation has become a challenge for farmers, especially in regions with sandy soils and degraded pastures. In this situation, the reimplantation of pasture is an alternative to create conditions for the good development of soybeans. The objective of the work was to evaluate the productivity of soybeans of first and second cultivation in sandy soil conducted after re-implanted pasture and fertilized with nitrogen and gypsum. The experiment was conducted in the western region of São Paulo, on soil classified as argissolo vermelho distroférrico. The experimental design was in randomized blocks with subdivided plot, in a 5x2, with four replications. The plots consisted of five doses of nitrogen and the subplots were composed by the absence and application of gypsum. The main treatments in the plot consisted of nitrogen doses (0, 100, 200, 300 and 400 kg ha-1) combined with the absence and application of gypsum (0 and 1,450 kg ha-1). Forage yield and bromatology were evaluated, as well as soybean yield and components, as well as changes in chemical and microbiological characteristics of the soil. The data obtained were submitted to the SISVAR statistical program, and the means were compared using the Tukey test at 5% probability. The crude protein content of the pasture was higher with the increase of nitrogen fertilization doses. The doses 200 and 300 kg ha-1 of nitrogen promoted greater microbial activity. The data of soybean productivity in the first harvest had a linear adjustment with nitrogen doses and with the application of gypsum. The productivity of the second crop was 188% higher than the first crop.