Coffee Science_v.15, 2020
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12726
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Item Phytotoxicity and leaf anatomy of young coffee plants subjected to herbicides exclusively and in associations(Editora UFLA, 2020) Rodrigues, Rafael Jorge Almeida; Gonçalves, Adenilson Henrique; Menicucci Netto, Pedro; Carneiro, Arthur Henrique Cruvinel; Castanheira, Dalyse Toledo; Guimarães, Rubens José; Carvalho, Gladyston RodriguesThe lack of work force and the damage that weeds can cause to coffee plants are the causes of the growing demand for selective herbicides to be used in coffee farming. Thus, the objective of this study was to evaluate the phytotoxicity symptoms and leaf anatomical characteristics of young coffee plants submitted to application isolated herbicides and also in associations. An experiment was carried out in a protected environment in randomized blocks: four replicates with coffee seedlings (Coffea arabica L.) cultivar “Topázio MG-1190”, grown in pots with a capacity of 11 liters of substrate. The herbicides applied, in isolation, were: pyrazosulfuron-ethyl (0.015 kg ha-1), saflufenacil (0.049 kg ha-1), imazetaphyr (0.1 kg ha-1), iodosulfuron-methyl (0.0035 kg ha-1), chlorimuron-ethyl (0.015 kg ha-1) and sethoxydim (0.184 kg ha-1). The latter was used in associations with the others. In addition, a control without herbicides was used. Phytotoxicity symptoms were evaluated up to 49 days after application (DAA) and anatomical characteristics at 65 DAA. Saflufenacil exclusively and inassociation with sethoxydim caused visual phytotoxicity symptoms in the leaves and negatively influence in the characteristics of the epidermis thickness of the adaxial face (EAD), thickness of the palisade parenchyma (PAP), thickness of the spongy parenchyma (SPP) and thickness of the mesophyll (MES). The other herbicides, isolated or in associations, didn’t cause phytotoxicity symptoms, but had negative influence in the anatomical parameters of the leaf blade. However they did not interfere with the paradermic parameters and the vascular bundle.Item Effect of water stress and Coffee ringspot virus on coffee leaf temperature and its relationship with Brevipalpus yothersi population(Editora UFLA, 2020) Nunes, Matheus Mancini Porfírio; Vechia, Jaqueline Franciosi Della; Andrade, Daniel Júnior deThe Brevipalpus yothersi Baker mite is a vector of Coffee ringspot virus (CoRSV), the causing agent of coffee ringspot disease. Knowing the mite-host interaction and the variables that improve the development of the mite are important in order to manage the disease. The aim of this work was to study the relationships of cause and effect between water availability and leaf temperature on population fluctuation of B. yothersi on coffee plants Coffea Arabica L. Inside a greenhouse, plants under four levels of field capacity: 25, 40, 55 and 70% were arranged in two groups: (1) infestation of viruliferous B. yothersi with CoRSV and (2) no mite infestation. Following the transfer of mites to coffee plants, leaf temperature was measured daily in order to calculate the Daily Water Stress Index (DWSI). At the end of this experiment, the mites present on coffee plants were quantified and leaf samples were collected for leaf nitrogen content measurements. It was found that plants infested with B. yothersi indicated higher values of DWSI and lower levels of leaf nitrogen content when compared to non-infested plants. Furthermore, plants on higher water availability revealed higher populations of B. yothersi.Item Histochemical approach of the mobilization of reserve compounds in germinating coffee seeds(Editora UFLA, 2020) Oliveira, Leonardo Araujo; Souza, Genaina Aparecida de; Silva, Bruno Tavares; Rocha, Antônio Augusto Gomes; Picoli, Edgard Augusto de Toledo; Pereira, Diego de Sousa; Donzeles, Sérgio Maurício Lopes; Ribeiro, Marcelo de Freitas; Ferreira, Williams Pinto MarquesThe endosperm of coffee beans is an important structure which is composed of different reserve compounds. In the present study, we followed anatomical features during the reserve mobilization of Coffea arabica L. cv ‘Catuaí’ seed samples, harvested at 20 different sites, after 0, 3, 6, 12, 24, 30 and 45 days of imbibition. Seed samples were properly stored for enzyme activity assessment and fixed in FAA solution (formaldehyde, acetic acid and ethanol, 1; 1; 18) and kept in ethanol 70% solution, for histochemical analysis. Alternatively, samples for phenolic compounds histochemical test were fixed in Ferrous sulfate in formalin. Fixed samples were cross-sectioned for detection of starch, lipids, essential oils, oleoresins, proteins, phenolic compounds, neutral polysaccharides, alkaloids, β-1,3 and β-1,4 glucans, and lignin. Overall, based on histochemical tests and enzyme activity, seed reserve mobilization was similar among the evaluated altitudes and mountainsides. During soaking, there is an intense consumption of reserve compounds, starting at the region close to the embryo. Reserve mobilization intensifies after root protrusion, from 12 days of soaking. The intensification of the reserve consumption concomitant with an increased activity of MDH is observed at the first 12 days, whereas SOD showed higher expression after 30 days of soaking. At the 30th day, little reserve is observed in the endosperm. At 45th day, cotyledon leaves are expanded, and the root system, constituted by the taproot and lateral roots, is well established.Item Use of foliar fertilizers as attenuators of injuries caused by glyphosate drift in young coffee plantations(Editora UFLA, 2020) Gonçalves, Ana Luisa Lucca; Pereira, Gustavo Antônio Mendes; Silva, Larissa Aparecida; Alves, Deivide Patrik; Pucci, Laís Franchini; Gonçalves, Victor Afonso Reis; Reis, Marcelo Rodrigues dosGlyphosate is the most used product for weed control in young coffee planting rows. The application is carried out in a directed way, avoiding the contact of the product with the crop. However, drift and consequent plant injuries frequently occur. An alternative to reduce these injuries is the use of attenuators capable of reducing the negative effects caused by this herbicide. Therefore, the objective of this study is to verify the efficiency of foliar fertilizers (Fertiactyl Pós® and Crop+) as attenuators of the toxic effects caused by the use of glyphosate in the coffee crop. Thus, coffee seedlings were subjected to different doses of the mixture of Fertiactyl Pós® with glyphosate and Crop+ with glyphosate. The treatments were applied on top of the plants. The percentage of coffee intoxication was evaluated at 14, 21, 28, 35, 42 and 90 days after application. At 90 days after application, height, leaf area and shoot and root dry matter were evaluated. Higher doses of glyphosate (1.44 and 2.88 kg ha-1) without the use of attenuators caused intoxication levels close to 80% at 28 and 90 DAA. The use of Fertiactyl Pós® and Crop+ reduced the injuries caused by the application of glyphosate, regardless of the dose of herbicide and fertilizers, but with different levels of action. All the morphological variables measured suffered a negative action with the isolated use of glyphosate, with a tendency to recover when the attenuators were applied. It is concluded that the two attenuators were efficient in suppressing the deleterious effects of glyphosate on coffee plants affected by this herbicide. For 0.720 kg ha-1 of glyphosate, the dose most used in the field, 8 L ha-1 is recommended for Fertiactyl Pós® and 4 L ha-1 for Crop+.Item Biochemical parameters of an Oxisol submitted to high doses of gypsum in the coffee culture(Editora UFLA, 2020) Naves, Andrêssa de Paula; Silva, Aline Oliveira; Barbosa, Marisângela Viana; Pinto, Flávio Araújo; Santos, Jessé Valentim dos; Saggin Junior, Orivaldo José; Guimarães, Paulo Tácito Gontijo; Carneiro, Marco Aurélio CarboneThe objective of this study was to determine the influence of increasing doses of agricultural gypsum on the quality of the soil biochemical parameters in coffee cultivation (Coffea arabica L.) over two climatic seasons in the Brazilian Cerrado. Soil samples were collected in two seasons (dry and rainy season), at 0.00 – 0.10 m depth of an Oxisol, submitted to doses 0 (GSA); 3.5 (G3.5); 7.0 (G7.0) and 14 (G14) t ha-1 of agricultural gypsum in the coffee planting line. The biochemical parameters evaluated were: total organic carbon (TOC); microbial biomass carbon (MBC); soil basal respiration (SBR); absolute enzymatic activities [Urease, acid phosphatase, hydrolysis of fluorescein diacetate (FDA)], and enzymatic activity per unit of MBC. The significant effect (p ≤ 0.05) of gypsum doses was observed for MBC and SBR, which were higher in the treatment with G7.0 application. TOC, the enzymatic activities of Phosphatase and the FDA showed no differences between treatments. On the other hand, the specific enzymatic activities by MBC were used to describe the differences between the doses of gypsum applied, generally with greater activity in treatments G7.0 and G14. The accumulated coffee productivity was higher in G14 treatment. The results presented confirmed that the biochemical parameters of the soil are key in the evaluation of changes in soil use, and that the increase in gypsum favors activity and microbial biomass.Item Physicochemical, microbiological, and sensory analysis of fermented coffee from Sierra Nevada of Santa Marta, Colombia(Editora UFLA, 2020) Cruz-O’Byrne, Rosmery; Piraneque-Gambasica, Nelson; Aguirre-Forero, SoniaThe evaluation of the physicochemical (pH, degrees Brix, and temperature), microbiological (fungi, yeasts, and bacteria), and sensory characteristics (sensory attributes, score, and quality classification) of coffee wet fermentation in the Sierra Nevada of Santa Marta (SNSM), Colombia, was carried out to understand its dynamics and the correlation that exists between them. The fermentation process lasted 36 hours and samples were taken every six hours. The pH and degrees Brix gradually decreased in the fermentation time and showed a high dependence on each other. In 36 hours, the pH went from 5.37 to 3.96 and the degrees Brix from 6.53 to 4.30 °Bx. Fungi had the most abundant population throughout the fermentation process compared to bacteria and yeasts. The beverages obtained showed a high quality where the classification of excellent specialty coffees prevailed. The highest beverage quality was characterized by its sweetness, high acidity, floral notes flavored with lemongrass and cardamom, it was obtained at 18 hours of fermentation related to the highest fungi (6.92 log CFU.g-1) and yeast population (6.01 log CFU.g-1) and the lowest bacteria population (3.85 log CFU.g-1). Evaluating the physicochemical, microbiological, and sensory characteristics of fermented coffee in the SNSM is important in generating specific knowledge related to the fermentation process and coffee quality in the region and constitutes a tool for future research.Item Using unmanned aerial vehicle and machine learning algorithm to monitor leaf nitrogen in coffee(Editora UFLA, 2020) Parreiras, Taya Cristo; Lense, Guilherme Henrique Expedito; Moreira, Rodrigo Santos; Santana, Derielsen Brandão; Mincato, Ronaldo LuizNitrogen is an essential element for coffee production. However, when fertilization do not consider the spatial variability of the agricultural parameters, it can generate economic losses, and environmental impacts. Thus, the monitoring of nitrogen is essential to the fertilizing management, and remote sensing based on unmanned aerial vehicles imagery has been evaluated for this task. This work aimed to analyze the potential of vegetation indices of the visible range, obtained with such vehicles, to monitor the nitrogen content of coffee plants in southern Minas Gerais, Brazil. Therefore, we performed leaf analysis using the Kjeldahl method, and we processed the images to produce the vegetation indices using Geographic Information Systems and photogrammetry software. Moreover, the images were classified using the Color Index of Vegetation and the Maximum Likelihood Classifier. As estimator tool, we created Random Forest models of classification and regression. We also evaluated the Pearson correlation coefficient between the nitrogen and the vegetation indices, and we performed the analysis of variance and the Tukey-Kramer test to assess whether there is a significant difference between the averages of these indices in relation to nitrogen levels. However, the models were not able to predict the nitrogen. The regression model obtained a R2 = 0.01. The classification model achieved an overall accuracy of 0.33 (33%), but it did not distinguish between the different levels of nitrogen. The correlation tests revealed that the vegetation indices are not correlated with the nitrogen, since the best index was the Green Leaf Index (R = 0.21). However, the image classification achieved a Kappa coefficient of 0.92, indicating that the tested index is efficient. Therefore, visible indices were not able to monitor the nitrogen in this case, but they should continue to be explored, since they could represent a less expensive alternative.Item Evaluation of the effect of Azospirillum brasilense inoculation on arabic coffee seedlings(Editora UFLA, 2020) Silva, Leonardo Caixeta da; Barbosa, Camila Karen Reis; Franco Junior, Kleso SilvaIn fabaceae, Azospirilum is used in association with Rhizobium bacteria to promote biological nitrogen fixation, making the plant tolerant to water stress and resulting in better nutrient utilization, obtaining a plant more productive and vigorousand increase roots for better nutrient uptake by the plant. However, there are no studies using coinoculation in Coffee. The objective of the study was to evaluate the effect of different doses of A. brasilense on the development of coffee seedlings. The experiment was carried out in Machado, southern Minas Gerais. The experimental design was completely randomized (DIC), with five treatments and nine replications, totaling 45 experimental plots. The experimental unit consisted of pots of 12 liters of capacity with a substrate composed of 70% soil and 30% of tanned manure and a coffee seedling of cultivar Catuaí Vermelho IAC 144. Treatments were composed with different doses (0, 0.75, 1.5, 2.25 and 3.0 mL) of Azospirillum brasilense inoculant from the Micro-Chemistry laboratory, Azofix®, having Ab-V5 strains, 1 x 108 cfu. mL-1 viable cells per mL. From stage V7, the seedlings received eight applications with a seven-day interval. The applying was done in the late afternoon, under favorable environmental conditions, using a hand sprayer. Evaluations were performed 150 days after the first application. The variables evaluated were shoot height (ALT) (cm); shoot fresh matter (MFPA) (g); root fresh matter (MFR) (g); leaf fresh matter (MFF) (g); stem diameter (DIA)(mm) and pivoting root length (CRP) (cm). It is concluded that the inoculation of coffee seedlings with bacteria of the species Azospirillum brasilense promotes greater growth of the pivoting root as well as the fresh matter of the whole root system of coffee seedlings.Item Soil chemical attributes in coffee growing with different agronomic techniques(Editora UFLA, 2020) Voltolini, Giovani Belutti; Silva, Larissa Cocato da; Alecrim, Ademilson de Oliveira; Castanheira, Dalyse Toledo; Resende, Laís Sousa; Rezende, Tiago Teruel; Guimarães, Rubens JoséThe objective was to evaluate the chemical attributes in a coffee growing area, according to different agronomic techniques used and their associations. The experiment was conducted in the field, from January 2016 to October 2018. Coffee was planted in January 2016, with Mundo Novo IAC 379-19 coffee seedlings, with a spacing of 3.6 m between rows and 0.75 m between plants in the planting row. The factors under study were arranged in a 3x2x5 factorial scheme, making a total of 30 treatments. In the plots, three soil managements were randomized (soil cover with polyethylene film, soil cover with brachiaria-grass and conventional management of spontaneous vegetation). In the subplots, two types of fertilizers (conventional and increased-efficiency fertilizer). In the sub-subplots, four soil conditioners (coffee husk, phosphogypsum, water retention polymer, organic compost), and the control without conditioner. Aimed to evaluate soil chemical attributes in coffee growing with different agronomic techniques through the evaluation of: soil pH, phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), aluminum saturation (m) and base saturation (V%). The use of fertilizers combined with the application of organic compost or coffee husk, provide increased soil pH, as well as the use of ecological management of brachiaria-grass. The use of organic compost as a soil conditioner increases phosphorus availability in the soil. Coffee husk, as a soil conditioner, is an efficient potassium source for the coffee crop. The use of organic compost and phosphogypsum increases the calcium and magnesium contents in the soil. The use of organic compost and coffee husk was efficient in increasing the base saturation grown with coffee. The use of organic compost, coffee husk and phosphogypsum reduced aluminum saturation in the soil. Treatments associated with the use of organic compost improve calcium, phosphorus and magnesium levels, increase pH and base saturation, besides decreasing aluminum saturation.Item Soil attributes and coffee yield in an agroforestry system(Editora UFLA, 2020) Jácome, Máximo Gerardo Ochoa; Mantovani, José Ricardo; Silva, Adriano Bortolotti da; Rezende, Tiago Teruel; Landgraf, Paulo Roberto CôrreaCoffee growing in an agroforestry system may provide improvements in soil chemical and physical attributes, increase crop yield and diversify production. However, there are few studies on coffee growing intercropped with high quality wood-producing species such as African mahogany, teak and Australian cedar. The objective of this study was to evaluate, in an agroforestry system, the effect of coffee intercropping with tree species and the density of these species on chemical and physical soil attributes and on coffee yield. The experiment was carried out in Santo Antônio do Amparo, MG, and Catuaí Vermelho IAC 99 coffee was used in a 3.4x0.7m spacing. A randomized block design with split plots was used, with one additional treatment and 4 replications. The treatments consisted, in the plot, of three tree forest species: Australian cedar, teak and African mahogany, used intercropped with coffee; and, in the subplots, two densities of these forest species: 82 plants ha-1 (13.6 m between rows and 9 m between plants) and 41 plants ha-1 (13.6 m between rows and 18 m between plants). The additional treatment consisted of conventional coffee cultivation growing without intercropping with the tree species. At 64 months after the experiment was set, when the forest species were still under development, soil samples were taken at a depth of 0 to 0.1 m to determine the following chemical attributes: pH in H2O, potential acidity, organic matter content, P-Mehlich, K+, Ca2+, Mg2+, S, B, Cu, Fe, Mn, Zn and base saturation (V%); and physical soil attributes: bulk density, macroporosity, microporosity, total porosity. Soil temperature at 0.05 m depth and coffee yield were also evaluated. Chemical and physical attributes, besides soil temperature, are similarly influenced with the cultivation of Australian cedar, teak and African mahogany, intercropped with coffee, in both densities, 82 and 41 plants ha-1, after 5 years of implementation of the agroforestry system. Coffee cultivation in agroforestry system with Australian cedar, teak and African mahogany increases the organic matter and P content of the soil, but acidifies the soil and does not influence its physical attributes. The agroforestry system with teak and African mahogany increases coffee yield.