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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Chemical analyses of flowers and leaves for nutritional diagnoses of coffee trees(Universidade Federal de Santa Maria, 2021) Zabini, André Vinicius; Martinez, Herminia Emilia Prieto; Neves, Júlio César Lima; Cruz, Cosme Damião; Valadares, Samuel VasconcelosThe chemical analysis of flowers has been studied for some crops. In coffee trees, the flower tissue analysis could anticipate the nutritional diagnosis. This study aimed to: (i) compare the mineral composition of coffee flowers and leaves; and to (ii) generate reference values for nutritional diagnosis of coffee trees, based on flower and leaf analysis. Nutrient content of flowers and leaves and coffee productivity were evaluated in 26 commercial farms located in Manhuaçu, MG, Brazil throughout three years. The critical nutrient content range in Flowers are respectively: 2.78 – 3.17, 0.23 – 0.28, 2.80 – 3.12, 0.30 – 0.37, 0.24 – 0.30, 0.15 – 0.18 dag kg-1 of N, P, K, Ca, Mg, and S; and 17 – 21, 12 – 18, 52 – 80, 26 – 43, and 28 – 48 mg kg-1 of Zn, Cu, Mn, Fe, and B. For leaves, the critical nutrient ranges are respectively: 2.63 – 2.86, 0.13 – 0.14, 2.13 – 2.33, 1.04 – 1.22, 0.27 – 0.33, 0.15 – 0.18 dag kg-1 of N, P, K, Ca, Mg, and S; and 9 – 14, 15 – 23, 80 – 115, 99 – 148, and 31 – 37 mg kg-1 of Zn, Cu, Mn, Fe, and B. The nutritional diagnosis of coffee trees for N, P, Ca, Fe, Cu, and Mn can be anticipated using flower analysis.Item Relationship between coffee leaf analysis and soil chemical analysis(Sociedade Brasileira de Ciência do Solo, 2018) Sousa, Jailson Silva; Neves, Júlio César Lima; Martinez, Herminia Emilia Prieto; Alvarez V., Víctor HugoResearch focused on adequate nutrition of plants is essential in modern coffee production to increase yield and develop more efficient management strategies with greater environmental and economic sustainability. The objectives of this study were to establish critical and optimal levels of soil fertility properties for high yielding Arabica coffee crops using the Boundary Line method and, then, relate the macronutrient contents in the diagnostic leaf of coffee to the macronutrients available in the soil using the Quadrant Diagram of the Plant-Soil Relationship (QDpsR). The study made use of a soil chemical analysis database, leaf macronutrient contents, and Arabica coffee yield from five representative coffee-growing regions in Minas Gerais. An analysis of data consistency was performed, and relative fruit yield (RFY) was related to the soil organic matter (SOM), P, K, Ca, and Mg contents in the soil, establishing the boundary line (BL) in each graph. Equations were adjusted from the BL points, and the equation that best fit was selected. Using the QDpsR method, the response plane was divided into four quadrants, where the total leaf contents of N, P, K, Ca, Mg, and S were plotted as a function of the contents of SOM, P, K, Ca, and Mg in the soil, on the y and x axes of the Cartesian coordinate system. The regression equations were adjusted to the pairs of points (y, x) of quadrants III and I and were used to estimate the macronutrient sufficiency ranges from the critical and optimal levels in the soil. The BL method was used to determine the class of good soil fertility for SOM, P, K, Ca, and Mg. The QDpsR method allows determination of response curves for leaf content as a variable of soil contents, making it possible to estimate the sufficiency ranges in the diagnostic leaf of coffee: 33.4-35.8 g kg -1 of N, 1.4-1.6 g kg -1 of P, 24.4-27.0 g kg -1 of K, 11.9-13.6 g kg -1 of Ca, 3.8-4.5 g kg -1 of Mg, and 1.4-1.8 g kg -1 of S; which were consistent with the sufficiency ranges considered suitable for the crop. This study demonstrated the importance of leaf analysis as a tool for evaluation of the nutritional status of Arabica coffee since the technique is consistent with the theoretical principles underlying it.Item Spacial distribution of fertigated coffee root system(Editora UFLA, 2017-01) Vicente, Marcelo Rossi; Mantovani, Everardo Chartuni; Fernandes, André Luís Teixeira; Neves, Júlio César Lima; Figueredo, Edmilson Marques; Delazari, Fábio TeixeiraThe development of coffee plant root system changes when subjected to drip irrigation and fertigation. This work aimed to evaluate the effects of different levels of fertigation on the development of coffee root system by drip irrigation in western Bahia. The experiment was carried out with Catuaí Vermelho IAC 144 coffee plants, of about 3.5 years of age, in the “Café do Rio Branco” farm, located in Barreiras – BA, and consisted of a complete randomized blocks design with 3 replicates. Treatments consisted of three levels of nitrogen and potassium fertilization (900/800, 600/500 and 300/250 kg ha -1 year -1 N and K2O), weekly distributed, by means of fertigation, throughout the process. After the fourth harvest, coffee root system was evaluated, and root length density (RLD) and root density (RD) were determined at different sampled layers. The highest root concentration, root length density (RLD), and root density (RD) were observed in the superficial layers of soil (0-20 cm), and under the dripline (30 and 70 cm from the orthotropic branch). Results showed that the lower the N and K2O levels, the higher was the development (RLD and RD) of the coffee root system.