Análise hiperespectral da Brachiaria brizantha cv. Marandú sob diferentes regimes de adubação de nitrogênio

The pasture represents a big fraction of the agricultural lands in Brazil, however, there is scarcity in the use of intensification techniques in the livestock creation. With the technological advance in agriculture, it is necessary to increase the productivity of this activity. In the last couple of decades, the remote sensing has been studied as a potential tool for monitoring and managing different types of cultures, including pastures. The use of remote sensing techniques shows satisfactory results in evaluating the ideal amount of nitrogen for the cultivation of different species of pasture. The objective of this study is to analyze the potential of field spectrometry to estimate levels of nitrogen fertilization, with data obtained from the canopy of a Brachiaria Briantha cv Marandú pasture. The experiment was conducted in the Escola Superior de Agronomia de Luiz de Queiroz (ESALQ-USP). Each experiment was separated on blocs at random, with subdivided portions and four repetitions, which received doses of 0, 50, 100 e 150 kg ha-1 of nitrogen. The Brachiaria Brizantha cv Marandú''s spectral behavior showed changes with the nitrogen doses especially in the near-infrared region, with the witness dose being the one that have set itself apart the most from the others. Thus, the used remote sensing system technique allowed for the identification of different effects of nitrogen fertilization in the forage. Palavras-chave: remote sensing, espectral behaviour, discriminant analyzes, sensoramiento remoto, comportamento espectral, análise discriminante.