Recovery of nitrogen from ammonium sulfate and nitrate by corn crop in no-tillage system

Abstract

The objective of this work was to evaluate the influence of different timing of nitrogen split application during corn crop seeding, on nutrient concentration of leaves and on corn yield, after two years of soybean cultivation; and to quantify the recovery of nitrogen fertilizer using the isotopic dilution technique (¹⁵N). Treatments consisted of 70 kg ha^-1 nitrogen application at corn crop seeding in distinct times: during seeding of oat, before corn seeding (8 days), at corn broadcasting (4–5 leaves), and at corn broadcasting (7–8 leaves). There is no difference for leaf nutrient concentrations and productivity of corn, after nitrogen supplementation at corn crop seeding, independently of application timing, after two years of soybean cultivation in no-tillage system. Nitrogen recovery is higher in the compartment plant, when applied in coverage, compared to the applied before corn seeding. The split application of nitrogen in coverage does not improve the recovery of fertilizer in a single application.