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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Ammonia volatilization from blends with stabilized and controlled-released urea in the coffee system(Editora UFLA, 2016-09) Chagas, Wantuir Filipe Teixeira; Guelfi, Douglas Ramos; Caputo, André Luiz Carvalho; Souza, Taylor Lima de; Andrade, André Baldansi; Faquin, ValdemarApplication of stabilized and controlled-release urea blends can reduce the losses of N-NH3 as compared to conventional urea. The aim of this study was to quantify ammonia volatilization from conventional nitrogen fertilizers and blends of urea + (urea + NBPT) + controlled release urea applied in drip irrigated coffee system. The experiment was conducted under field conditions in in a Red Latosol located in Lavras-MG, Brazil. The randomized complete block design with six treatments: Urea = 450 kg ha -1 yr -1 N (100% of the recommended dose) divided in three splittings equal to 150 kg ha -1 N with an interval of 50 days; ammonium nitrate = 450 kg ha -1 yr -1 N (100% of the recommended dose) in three splittings equal to 150 kg ha -1 N with an interval of 50 days; Polyblen Extend ® -100%= 450 kg ha -1 yr -1 (100% of the recommended dose) applied in two splittings, 315 kg ha -1 N in the 1o split and 135 kg ha -1 N in the 2o split; Polyblen Extend ® -70% = 315 kg ha -1 yr -1 N (70% of the recommended dose) in two splittings, 220.5 kg ha -1 N in the 1o split and 94.5 kg ha -1 N in the 2o split; Polyblen Montanha ® -100% = 450 kg ha -1 yr -1 (100% of the recommended dose) in an unique application in the 1o split and Polyblen Montanha ® -70% = 315 kg ha -1 yr -1 N (70% of the recommended dose) at an unique application in the 1o split, with three repetitions. Total accumulated N-NH3 losses followed the decreasing order: Urea (83.2 kg ha -1 N) > Polyblen Extend ® - 100% (60.3 kg ha -1 N) > Polyblen Montanha ® - 100% (46.8 kg ha -1 N) > Polyblen Extend ® - 70% (35.1 kg ha -1 N) > Polyblen Montanha ® - 70% (24.2 kg ha -1 N) > nitrate ammonium (2.0 kg ha -1 N ). The use of Polyblen Montanha ® decreases two splittings compared to conventional sources such as urea and ammonium nitrate, by applying only 70% of the recommended dose without affecting yield and coffee crop nutrition.