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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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2014 - 20193

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Tem arquivos: SimAssunto: search.filters.subject.Eficiência agronômica

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    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.
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    Effect of potassium sources and rates on arabica coffee yield, nutrition, and macronutrient export
    (Sociedade Brasileira de Ciência do Solo, 2014-09) Mancuso, Mauricio Antonio Cuzato; Soratto, Rogério Peres; Crusciol, Carlos Alexandre Costa; Castro, Gustavo Spadotti Amaral
    The use of potassium (K) rock powder can be an alternative for K supply of crops. Thus, to reduce K fertilizer imports from abroad, possibilities of extracting this nutrient from Brazilian rocks are being studied. The objective was to evaluate the effect of phonolite rock powder (F2) as K source (Ekosil ® ) on the air-dried fruit yield, nutrition and macronutrient export of Arabica coffee. The experiment was carried out on a dystroferric Red Latosol (Typic Haplorthox), in Piraju, São Paulo State, Brazil, in the 2008/09 and 2009/10 growing seasons. The experimental design was a randomized complete block, in a factorial 2 × 3 + 1 arrangement, with four replications. The treatments consisted of two K sources (KCl - 58 % of K 2 O and F2 - 8.42 % K 2 O) and three rates 1⁄2-, 1-, and 2-fold the K 2 O rate recommended for coffee, i.e., 75, 150, and 300 kg ha -1 of K 2 O), plus a control (without K application). Potassium supply increased coffee yield, regardless of the source. Application of source F2 increased coffee yield similarly to KCl at the recommended K rate for coffee (150 kg ha -1 K 2 O), proving efficient as K supply for coffee. Potassium application increased macronutrient export in coffee, especially in the growing season with higher yield.
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    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 ®