Coffee Science_v.16, 2021

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12727

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Resultados da Pesquisa

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    Leaf anatomy, physiology and vegetative growth of fertigated Coffee arabica L. trees after exposure to pruning
    (Editora UFLA, 2021) Soares, Daiane dos Santos; Silva, Elisângela Aparecida da; Carvalho, Milene Alves de Figueiredo; Pereira, Fernanda Aparecida Castro; Guimarães, Rubens José
    In coffee plants, fertigation can be an alternative way to minimize the negative effects exerted by drought and maximize fertilizer use efficiency. However, the fertilization recommendations for fertigated coffee trees are still not very specific, and the recommendations for rainfed crops are used. In addition, little is known about the nutritional requirements for fertigated coffee trees that have undergone the low recepa pruning treatment. Thus, the objective of this study was to evaluate the effects of different levels of nitrogen (N), phosphorus (P), and potassium (K) fertilizers on leaf anatomy, physiology, and veg etative growth of fertigated coffee trees (Coffea arabica L.) that have been under the low recepa pruning treatment. During the first five years of growth, the cultivar Topázio MG-1190 of the coffee crop received 10, 40, 70, 100, 130, and 160% of the fertilization levels recommended for the rainfed coffee crop. After this period, the crop was exposed to low recepa pruning. It was concluded that different doses of N, P, and K fertilizers modified the internal structure of coffee plant leaves, as well as physiological responses and plant growth; there was stronger vegetative growth, sharper leaf blade, greater thickness of spongy parenchyma, larger phloem area, and higher xylem relative hydraulic conductivity as the N, P, and K fertilizer levels in fertigated coffee (Coffea arabica L.) plants, which received the low recepa pruning treatment, increased. This knowledge can be used as a solid basis for main fertilization recommendations for fertigated coffee trees after exposure to the low recepa pruning treatment.
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    Manganese and fluorine suppress bacterial blight on coffee seedlings grown in a nutrient solution
    (Editora UFLA, 2021) Velloso, Jeanny Alice; Pozza, Edson Ampelio; Pozza, Adelia Aziz Alexandre; Silva, Humberson Rocha; Pérez, Cristian David Plaza; Souza, José Otávio Gusmão de
    The use of manganese (Mn) and fluorine (F) in the management of bacterial blight were evaluated in coffee seedlings grown in a nutrient solution. The experiment was carried out with the cultivar Catuaí Vermelho IAC 99. The treatments consisted of the combination of five doses of Mn with five of F, applied via leaf, using Mn sulfate and sodium fluoride, in a 5x5 factorial scheme. The plants were inoculated with bacterial suspension seven days after foliar application of F and Mn doses. The incidence and severity assessments were performed at an interval of 24 hours for 10 days. Photosynthetic activity was assessed using the infrared gas analyzer. Stomatal conductance, photosynthesis, transpiration, PAR radiation and internal CO2 were ana lyzed. The chlorophyll content was calculated indirectly. The leaf analysis was performed by digestion in HNO3 to determine the levels of Mn. Variables such as Area Under Incidence Disease Progress (AUIDP), Area Under Severity Disease Progress (AUSDP), chlorophyll a, b, and total concentrations and photosynthesis were submitted to the Shapiro-Wilk test. The treatment means were subjected to linear regression analysis. Data were analyzed using software R. There was a significant interaction (P <0.05) between the concentrations of Mn and F for the AUIDP and (AUSDP). Doses between 0.7 and 1.4 g L-1 of Mn combined with doses of 0.10 to 0.12 g L-1 of F were more effective in suppressing the bacterial blight, after analysis for both variables. The increase in Mn concentrations in leaves reduced liquid photosynthesis. The interaction between Mn and F suppressed the bacterial blight intensity of the coffee plants in nutrient solution.
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    Nutritional efficiency in phosphorus of arabica coffee genotypes
    (Editora UFLA, 2021) Vilela, Diego Júnior Martins; Coelho, Larissa Sousa; Silva, Douglas Ramos Guelfi; Carvalho, Gladyston Rodrigues; Botelho, Cesar Elias; Ferreira, André Dominghetti
    Nutritional efficiency is a term used to characterize plants in their capacity to uptake and use nutrients, being related to the efficiency of uptake, translocation, and utilization of nutrients. Different coffee genotypes are expected to exhibit variability in their nutritional efficiency. This work aimed to evaluate the phosphorus nutritional efficiency in arabica coffee genotypes. The experiment was carried out in a greenhouse of the Empresa de Pesquisa Agropecuária de Minas Gerais (EPAMIG), located in the municipality of Lavras – Minas Gerais, Brazil. The experimental design was a randomized complete block design, in a 10x2 factorial scheme (10 arabica coffee genotypes and two dosages of phosphate fertilization), with four replicates. Each experimental plot consisted of one pot with ten liters of soil, with one plant. The cultivars Catiguá MG2, MGS Ametista and Sarchimor MG 8840 are neither efficient nor responsive to phosphate fertilization. Progeny H 6-47-10 pl. 3 and the cultivar Catuaí Vermelho IAC 144 are not efficient but are responsive to phosphate fertilization. The cultivars Paraíso MG H 419-1, Topázio MG 1190 and MGS Paraíso 2 are efficient but are not responsive to phosphate fertilization. The cultivars Bourbon Amarelo IAC J10 and MGS Aranãs are efficient and responsive to phosphate fertilization.