Navegando por Autor "Andrade, André Baldansi"

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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, Valdemar
Application 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.
Monoammonium phosphate coated with polymers and magnesium for coffee plants
(Editora UFLA, 2018-05) Guelfi, Douglas Ramos; Chagas, Wantuir Filipe Teixeira; Lacerda, Jordana Reis; Chagas, Rafael Mattioli Rezende; Souza, Taylor Lima de; Andrade, André Baldansi
The coating of phosphate fertilizer granules with polymers and magnesium (Mg) is a technology that can improve phosphorus (P) use efficiency and mitigate problems of low Mg supply in coffee crops. The objective of this work was to evaluate the growth and nutrition characteristics of coffee seedlings and the agronomic efficiency (AE) of monoammonium phosphate (MAP) coated with anionic polymers and Mg in comparison with other phosphate fertilizer technologies. The experiment was carried out in a greenhouse in 20 L pots. Two five-month-old coffee seedlings were transplanted into each pot. The experimental design was completely randomized with three replicates. The following treatments, applied at a dose corresponding to 20 g pot -1 of P 2 O 5 , were carried out: MAP; MAP coated with anionic polymers (Policote Phós ® ); MAP coated with anionic polymers+Mg (Policote Phós_Mg ® ); Top-Phós ® ; and Agrocote ® . A control (without P) was prepared. Plant height; leaf area; dry mass of leaves, stems, and roots; total dry mass; shoot/root ratio; specific leaf weight; P and Mg content in plants and their availability in the soil after cultivation and efficiency indicesof the phosphate fertilization treatment were evaluated. The recovery of applied P and the agronomic efficiency of phosphate fertilizers was found to increase in the following order: MAP = Top-Phós ® = Agrocote ®
Nitrogen fertilizers technologies for coffee plants
(Editora UFLA, 2019-01) Chagas, Wantuir Filipe Teixeira; Silva, Douglas Ramos Guelfi; Lacerda, Jordana Reis; Pinto, Leandro Campos; Andrade, André Baldansi; Faquin, Valdemar
The application of urea in coffee crop has caused high losses of nitrogen (N) by volatilization, causing low use and recovery of this nutrient. This low use of N may interfere in the growth and nutrition of the coffee crop and thus, influence the efficiency of the nitrogen fertilization. The aim in this work was to assess the growth, nutritional and physiological characteristics and the agronomic efficiency of the nitrogen fertilization with different nitrogen fertilizer technologies. The experiment was performed in a greenhouse in pots with a volume of 14 L. In each pot, it was performed the transplanting of two plants of coffee. The experimental design was entirely randomized, with four replicates. The following nitrogen fertilizers were applied in the dose of 10g pot -1 , devided into three applications with interval of 50 days: Conventional urea; ammonium nitrate; urea + formaldehyde; Polyblen Extend ® ; Polyblen Montanha ® ; Urea + polyurethane; urea + plastic resin; ammonium sulfate + CaCO 3 and the control, without N application. After cropping, it was evaluated the growth, nutritional and physiological parameters. Afterward, it was calculated two agronomic efficiency index of the nitrogen fertilization. The highest values of plants height, the total dry mass of plants and leaf area in coffee seedlings were found with the application of Polyblen Extend ® . This blend also provided higher accumulation of N in the leaf and the whole plant. The application of Polyblen Extend ® provided higher agronomic efficiency and also enhanced the photosynthetic rate in the coffee plants.