Doses, fontes e épocas de aplicação de nitrogênio em cultivares de arroz

Abstract

Nitrogen is a nutrient that can be lost through leaching, volatilization and erosion. Crops require nitrogen in different doses and application times. The objective of this work was to evaluate the performance of BRSMG Curinga and IAC 202 rice to application of five doses of nitrogen (0, 50, 100, 150 and 200 kg of N ha-1) using three nitrogen sources (ammonium sulfonitrate with nitrification inhibitor, ammonium sulfate and urea), at two times of application (at sowing or at tillering stage), with sprinkler irrigation. A randomized block design was used in a 5x3x2x2 factorial scheme, with four repetitions. The Curinga rice showed the highest grain yield. The doses of N increased the foliar N content, the height of plants, the number of panicles m-2, the number of full grains panicle-1, the mass of full grains per panicle and the grain yield, but did not influence the mass of 100 grains. The time of application and the nitrogen sources had a similar effect in all evaluations. The highest grain yield was reached with a dose of 122 kg of N ha-1, regardless of the source.