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Item Influence of flowering and additional fertilization on physical and sensory aspects of arabica coffee(Universidade Federal Rural de Pernambuco, 2019) Rocha, Richardson Sales; Simão, João Batista Pavesi; Peluzio, João Batista Esteves; Ferrari, Jeferson Luiz; Gravina, Geraldo de AmaralIn Caparaó region, Brazil, in areas above 1000 m high, a second flowering (called late or from March) is common to take place, causing changes in the crop management for those intending to produce specialty coffees. The objective of this study was to evaluate physical and sensory aspects of arabica coffee from the Caparaó region, produced in traditional and late plantations in the same fields, using two fertilization regimes, one recommended by specific literature and another with the addition of extra fertilizers (33%), respecting the proportions amid them. The employed factorial analysis allowed identifying the interaction between the two levels of nutrition and the two harvests, for the analyzed attributes. The extra addition of fertilizers provided a reduction in the mean score of the fragrance/aroma and overall sensory attributes in the traditional harvest; and in the late harvest, it alone was responsible for raising the scores of the following sensory attributes: flavor, aftertaste, acidity, balance and total. The added extra amount of fertilizer, unassisted, altered the coffee physical aspects, reducing their defects/imperfections.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 Effect of cover crops and bioactivators in coffee production and chemical properties of soil(Editora UFLA, 2018-10) Franco Junior, Kleso Silva; Terra, Ana Beatriz Carvalho; Teruel, Tiago Rezende; Mantovani, José Ricardo; Florentino, Ligiane AparecidaCoffee cultivation has great socio-economic relevance in Brazil for the employment and income generation and there is currently a constant search for sustainable management techniques. Among them, we can mention the use of cover crops and soil bioactivators. However, studies relating the use of these two techniques are still incipient. Based on this, the objective of this research was to evaluate the effect of the Penergetic® bioactivator associated with different cover crops on chemical properties of soil and coffee productivity. The experiment was carried out in a coffee field with Catuaí Vermelho cultivar IAC 144, in a randomized block design in a factorial scheme 4 (soil cover) x 2 (use or not of the Penergetic® bioactivator), consisting of control (without plant cover); oats (Avena strigosa) + forage turnip (Raphanus sativus ); oats (Avena strigosa) + forage turnip (Raphanus sativus ) + lupine (Lupinus albus) + rye (Secale cereale) + vetch (Vicia sativa); Brachiaria brizantha (Urochloa brizantha), associated or not with the use of the Penergetic® bioactivator. The experiment was conducted for 6 months and after that period, the chemical properties of soil, the nutrient contents of the coffee plants, the development of the branches and the coffee productivity were analyzed. Data were analyzed by the Scott Knott test at 5% probability. It was verified the interaction between cover crops and the use of the Penergetic® bioactivator, positively influencing soil chemical characteristics, coffee nutrition and productivity.Item Magnesium in the dynamics of carbohydrates and antioxidant metabolism of coffee seedlings in two irradiance levels(Editora UFLA, 2018-07) Dias, Kaio Gonçalves de Lima; Guimarães, Paulo Tácito Gontijo; Furtini Neto, Antônio Eduardo; Faquin, Valdemar; Pádua, Eduane José de; Silveira, Helbert Rezende Oliveira deThe aim of this study was to verify the physiological impacts and the carbohydrate dynamics of Coffea arabica, seedlings subjected to increasing concentrations of magnesium (Mg) and two irradiance levels. Methods: The experiment was carried out in growth chambers with nutrient solution. The treatments were five concentrations of Mg (0, 48, 96, 192, and 384 mg L-1 ) and two irradiance levels (80 and 320 μmol of photons m-2 s-1 ). The coffee seedlings were under the treatments for 90 days. Results: The leaves with deficiency or excess of Mg exposed to the irradiance of 320 μmol of photons m -2 s-1 accumulated more carbohydrates than those exposed to 80 μmol of photons m 2 s-1 . The accumulation of carbohydrates in the leaves increased the activity of antioxidant enzymes due to the increased production of reactive oxygen species (ROS). Leaves exposed to 320 μmol of photons m-2 s-1 exhibited symptoms of scald by the sun caused by photo-oxidation. The scald was more intense in plants with abnormal concentrations of Mg. The antioxidant system of the coffee tree is closely relates to the Mg supply and irradiance levels. Concentrations of Mg between 48 and 96 mg L-1 functioned as a mitigating agent of oxidative stress under stressful conditions caused by high irradiance level.Item Coffee leaf and stem anatomy under boron deficiency(Sociedade Brasileira de Ciência do Solo, 2007-05) Rosolem, Ciro Antonio; Leite, Vagner MaximinoBoron deficiency in coffee is widely spread in Brazilian plantations, but responses to B fertilizer have been erratic, depending on the year, form and time of application and B source. A better understanding of the effects of B on plant physiology and anatomy is important to establish a rational fertilization program since B translocation within the plant may be affected by plant anatomy. In this experiment, coffee plantlets of two varieties were grown in nutrient solutions with B levels of 0.0 (deficient), 5.0 μM (adequate) and 25.0 μM (high). At the first symptoms of deficiency, leaves were evaluated, the cell walls separated and assessed for B and Ca concentrations. Scanning electron micrographs were taken of cuts of young leaves and branch tips. The response of both coffee varieties to B was similar and toxicity symptoms were not observed. Boron concentrations in the cell walls increased with B solution while Ca concentrations were unaffected. The Ca/B ratio decreased with the increase of B in the nutrient solution. In deficiency of B, vascular tissues were disorganized and xylem walls thinner. B- deficient leaves had fewer and deformed stomata.Item Coffee yield and phosphate nutrition provided to plants by varius phosphorus sources and levels(Editora UFLA, 2015-03) Dias, Kaio Gonçalves de Lima; Furtini Neto, Antônio Eduardo; Guimarães, Paulo Tácito Gontijo; Reis, Thiago Henrique Pereira; Oliveira, Cesar Henrique Caputo dePhosphorus (P) is considered one of the nutrients that most limits crop yields, especially in soils with an advanced degree of weathering. To evaluate P dynamics and availability in soil resulting from various P doses and sources and to assess the resulting P content of coffee leaves and the final coffee yield, an experiment was conducted in the municipality of Três Pontas, MG, Brazil, in a Red Argisol (Ultisol) area. Fertilization, except for P fertilization, was performed based on the soil analysis results. The annual P doses tested were 0, 75, 150, 300, 450 and 600 kg ha-1 P2O5. Two P sources, simple superphosphate and magnesium thermal phosphate, were evaluated and compared in the study. A physicochemical analysis of the soil and an analysis of leaf dry matter were performed. The available P content in the soil increased as a result of the applications of the two sources. The leaf P levels stabilized at approximately 1.8 and 1.9 g kg -1 for simple superphosphate and magnesium thermal phosphate, respectively, as a result of the application of approximately 300 kg ha-1 P2O5 . The coffee responded to P fertilization in the production phase. Averaged over three harvests, the yield per harvest showed gains of 45.3% and 40.3% for simple superphosphate and magnesium thermal phosphate, respectively, with the application of the highest studied dose, 600 kg ha-1 P2O5.Item Cobre via foliar na nutrição e na produção de mudas de cafeeiro(Editora UFLA, 2015-10) Dias, Kaio Gonçalves de Lima; Carmo, Davi Lopes do; Pozza, Adélia Aziz Alexandre; Pozza, Edson Ampélio; Guimarães, Paulo Tácito GontijoObjetivou-se, com este estudo, avaliar o efeito de fontes e doses de cobre (Cu) aplicado via foliar na nutrição e na produção de mudas de cafeeiro. Os tratamentos consistiram de combinações de duas fontes (Sulfato Cúprico Amoniacal - SCA e Sulfato de Cobre - SC) e quatro doses (0, 250, 500 e 1000 g ha -1 ) de Cu. As fontes de Cu nas diferentes doses foram dissolvidas em água e calculadas para o volume de pulverização foliar de 400 L ha -1 de calda. As doses foram parceladas em três aplicações espaçadas de 20 dias. Avaliaram-se os teores e o conteúdo de Cu na folha, no caule, na raiz e total das plantas; a matéria seca da folha, caule, raiz e total; a eficiência de utilização, a eficiência de absorção e a eficiência de translocação em mudas de cafeeiro. De modo geral,os maiores teores e conteúdos de Cu foram obtidos para a fonte SC. Os incrementos máximos de matéria seca total foram de 48 g para o SCA e de 51 g para o SC, para as doses de 534 e 668 g ha -1 , respectivamente. As maiores eficiências de utilização e de absorção foram constatadas para o SCA e SC, respectivamente. A eficiência de translocação foi semelhante para as duas fontes.