Nitrogen management in mombasa guineagrass as a function of sources and rates of nitrogen

Abstract

Nitrogen is the nutrient that most influences productivity and quality of pastures. The objective was to study the management of a pasture with high productive potential using different sources and nitrogen rates (N), to contribute to the development of livestock by quantifying  dry matter yield (DMY), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (FDA), and leaf chlorophyll index (ICF - SPAD). The experiment was developed in Ilha Solteira - SP, in a Acrisol Dark eutrophic, sandy textured. The experiment was arranged as a randomized complete block design with four replications, with five sources of nitrogen: urea; ammonium sulfonitrate; ammonium nitrate; ammonium sulfate; and sulfammo - source of slow release N associated with sea kelp calcium carbonate. Urea was used at five N rates (0, 50, 100, 150 and 200 kg ha^-1 per harvest) to determine the effectiveness of other nitrogen fertilizers, which have been tested in a single dose of 100 kg ha^-1 of N per harvest. The use of sulfonitrate of ammonium and sulfammo at a rate of 100 kg ha^-1, were more efficient in making nitrogen available to the mombasa guineagrass, increasing LCI and CP, reflecting higher DMY.