Adubação nitrogenada foliar sobre a produção de pastagens: revisão de literatura

Abstract

In tropical pastures, nitrogen is important because its deficiency, common in soils of these regions, limits productivity and results in a sharp drop in carrying capacity and animal weight gain. Despite the benefits of nitrogen fertilization, its application has a short-term effect on tropical soils, because processes that interfere with the complex dynamics of N in the soil (leaching, volatilization, immobilization-mobilization, nitrification, denitrification and mineralization) and its relationship with the plant, can cause major changes in the availability of this nutrient for forage crops. Foliar application of fertilizer is an alternative for reducing losses of this element. Therefore, the present work aims to review the literature on the benefits of foliar fertilization compared to conventional fertilization in pastures. Foliar fertilization has objectives such as: correct any deficiencies within the plant cycle; supply of micronutrients; increase the efficiency of nutrient use and can be associated with herbicide grouts, aiming to supply nutrients to the crop and improve the characteristics of the grout. Foliar fertilization allows greater forage production and utilization of N-fertilizer, but it is an auxiliary practice to conventional fertilization and not a substitute for it. In comparison to conventional fertilization, it can be observed that foliar N fertilization is limited by the low leaf area after grazing and the impossibility of supplying large doses of N to the pasture. In contrast, N losses when applied via foliar are reduced.