Coffee Science (E-Journal)
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Characterization of the coffee fruit detachment force in crop subjected to mechanized harvesting
Get PDFIn order to adjust the coffee harvester and to assist in deciding either whether or not to make a second pass of the harvester, fully or selectively, it is necessary to know some crop parameters. The aim of the present study was to evaluate the coffee fruit detachment force in the green and cherry ripeness, under different plant positions and in four evaluation periods, throughout the harvest period between the first and second pass of harvester. The cultivar used was the Catuaí Amarelo IAC 144 aged eight years in spacing 3.8 x 0.9 m. Detachment force was determined by sampling using a portable digital dynamometer. The green ripeness stage showed superior detachment force than the cherry for all evaluation periods. The fruit detachment force for the green and cherry ripeness showed a decreasing behavior during the evaluation period, since the difference between the detachment forces of these fruits increased, thus guiding the type of harvest to be performed. Beyond the fruit detachment force difference, other parameters such as fruit ripening rate and crop load were essential for harvest management. Significant variations were identified in the fruit detachment force positioned in different parts of the coffee tree branches. The results also reinforce the relevance of characterizing the coffee fruit detachment force for harvester adjustments and management of the selective mechanized harvesting
COMPETITIVE PRESSURES ON THE ARTISAN COFFEE ROASTER SEGMENT IN THE STATE OF MINAS GERAIS, BRAZIL: A MULTI-CASE STUDY
Get PDFThe specialty coffee market is still little known and underexplored in Brazil, motivating an analysis of the competitive pressures and structure of the artisan coffee roaster segment in the state of Minas Gerais, in order to better understand it and encourage the adoption of specific policies for its expansion, besides comparing it to the commodity coffee roasting segment. A multi-case study was performed with three companies in this segment through in-depth interviews with their owners. There were significant changes in the competitive forces that shape the coffee industry, when comparing the specialty and commodity coffee segments, both in intensity and in motivations. Among the suggested policies to support the specialty coffee segment are its promotion and dissemination through “consumer education” and awareness raising on the differentiated properties of these products, besides providing subsidized courses and specializations for those who wish to be involved in this marketplace
Intercropping period between species of green manures and organically-fertilized coffee plantation
Get PDFThe adequate supply of nitrogen to coffee plantation is one of the main challenges of organic agriculture. The aim of the present study was to evaluate the effect of organic fertilization with two legume species in different intercropping periods on nitrogen nutrition, initial growth and productivity of coffee plantation. The experimental design was in randomized blocks, in 2x4 split-plot factorial design, being that the plot consisted of two intercrops (coffee+jack bean and coffee+hyacinth bean) and the four intercropping periods (30, 60, 90 and 120 days after sowing of the legume), and the subplot by 50% and 100% of fertilization for the coffee plantation. The increase in the intercropping period between legumes and coffee plantation favored a greater increase in height and node number of coffee trees, besides showing higher heights when fertilized with 50% of the recommended dose and intercropped with hyacinth bean. The intercropping with the hyacinth bean resulted in a larger crown diameter of coffee trees in 2010 and a larger diameter accumulated in the two evaluated years. Higher N contents were found in coffee trees fertilized with 100% of the recommended dose. The legumes supplied the nutritional requirements of the coffee harvest fertilized with 50% of the dose. The bean yield of the processed coffee is not affected by the intercropping with the green manures of jack bean or hyacinth bean
MAGNESIUM IN THE DYNAMICS OF CARBOHYDRATES AND ANTIOXIDANT METABOLISM OF COFFEE SEEDLINGS IN TWO IRRADIANCE LEVELS
Get PDFThe 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
SAPROBIC FUNGI AS BIOCONTROL AGENTS OF HALO BLIGHT (Pseudomonas syringae pv. garcae) IN COFFEE CLONES
Get PDFHalo blight caused by Pseudomonas syringae pv. garcae is a limiting disease in coffee production. There are few efficient commercial products on the market to control this disease, and therefore, the prospection of different biocontrol agents is a promising alternative. The objectives in this study were (i) to select saprobic fungi with the potential to control halo blight in coffee clones, and (ii) to evaluate the contributions of induced resistance as control mechanisms. Plants were sprayed with Gonytrichum chlamydosporium, Phialomyces macrosporus, and Moorella speciosa 7 d before inoculation with Pseudomonas. syringae pv. garcae. The area under the halo blight progress curve (AUDPC) and plant growth parameters were evaluated. M. speciose and G. clamydosporium did not reduce the AUDPC and even reduced plant growth in none of the trails compared to the water control. P. macrosporus consistently reduced AUDPC by 42 - 72% and increased plant height by 40%. Thereafter, the contributions of induced resistance was evaluated for the P. macrosporus, selected as the most promising biocontrol agent.. In order to determine induced resistance, phenylalanine ammonia lyase (PAL), peroxidase (POX), and ascorbate peroxidase (APX) activity of plant leaves were measured at two time points after stress challenge. Enzyme activity evaluation demonstrated high activity of POX and PAL at seven days after treatment with the saprobe, and high APX activity after 14 days. The results of this study indicate that P. macrosporus has the potential to be used in the management of coffee halo blight in seedling production, and one mechanism likely involved is induced resistance
OCCUPATIONAL NOISE LEVEL IN MECHANIZED AND SEMIMECANIZED HARVEST OF COFFEE FRUITS
Get PDFCoffee cultivation has undergone significant changes, especially with regard to the mechanization process of the various existing operations that were previously carried out manually by the workers. It is observed that the intensification of mechanized activities can expose workers to noise levels capable of compromising their hearing health. In this sense, the objective of the present study was to determine the level of occupational noise in the activities of mechanized and semi-mechanized harvesting of coffee fruits and compare them with the limits of tolerance of the current legislation. The occupational noise level was determined considering the exposure of homogeneous groups, using an integrative meter for personal use, noise dosimeter, electromechanically calibrated and with field calibration. The results demonstrate that the noise levels found are above the limits allowed for an 8-hour working day. The highest observed level was 100.66 dB (A) in the sweeping operation with the blower equipment and the lowest level 89.05 dB (A) in the auxiliary activity of the selected collection equipment Vicon H3000. Harvesting activity with a portable mechanical stripper equipment showed a noise level 4.07% higher compared to harvesting with automotive harvester equipment.Coffee cultivation has undergone significant changes, especially with regard to the mechanization process of the various existing operations that were previously carried out manually by the workers. It is observed that the intensification of mechanized activities can expose workers to noise levels capable of compromising their hearing health. In this sense, the objective of the present study was to determine the level of occupational noise in the activities of mechanized and semi-mechanized harvesting of coffee fruits and compare them with the limits of tolerance of the current legislation. The occupational noise level was determined considering the exposure of homogeneous groups, using an integrative meter for personal use, noise dosimeter, electromechanically calibrated and with field calibration. The results demonstrate that the noise levels found are above the limits allowed for an 8-hour working day. The highest observed level was 100.66 dB (A) in the sweeping operation with the blower equipment and the lowest level 89.05 dB (A) in the auxiliary activity of the selected collection equipment Vicon H3000. Harvesting activity with a portable mechanical stripper equipment showed a noise level 4.07% higher compared to harvesting with automotive harvester equipment
Characterization of coffee cultivars leaf rust-resistant subjected to framework pruning
Get PDFThe goal of our work was to evaluate physiological and agronomic traits, as well as the relationship between these traits in coffee cultivars coming from a germplasm supposedly resistant to leaf rust, and their response to framework pruning. The experiment was conducted at the Federal University of Lavras in randomized blocks with three replicates, with spacing of 3.5 x 0.7 m and plots of 12 plants. An amount of 25 coffee cultivars was evaluated, from which 23 were considered resistant and two susceptible to leaf rust. Traits analyzed were the plagiotropic branch length and number of nodes, net photosynthetic rate, transpiration rate, water use efficiency, fluorescence and chlorophyll index, leaf area index, leaf rust incidence and yield. Catucaí Amarelo 20/15 cv 479, Araponga MG1 and Tupi IAC 1669-33 cultivars show highly responsive to framework pruning. These cultivars have high yield associated to high net photosynthetic rate, water use efficiency and low transpiration rate. Moreover, the last two cultivars show a low incidence of leaf rust. The Acauã cultivar has a good response to framework pruning, showing high yield associated to lower incidence of leaf rust. Catucaí Vermelho 785/15 cultivar is not responsive to framework pruning because show lower yield, high incidence of leaf rust, low vegetative growth and low water use efficiency
SENSORY PROFILE OF BRAZILIAN COFFEES BASED ON CONSUMER PERCEPTION AS AN ALTERNATIVE TO THE CONVENTIONAL METHODS
Get PDFConsumer-based methodologies for sensory characterization of foods have been widely discussed and are satisfactory, when compared to the results of trained panelists. However their efficiency in the description of complex foods rich in sensory attributes (flavor and aroma) such as coffee still needs to be explored. Polarized sensory positioning (PSP) is an innovative methodology for sensory characterization, based on the comparison of samples with reference products. In this study, roasted and ground coffees with different quality ratings according to the Coffee Quality Program (PQC) of the Brazilian Coffee Industry Association (ABIC) - Traditional, Superior and Gourmet – were evaluated by this method, applied to consumers. The beverage was presented to 100 consumers, who quantified the degree of global difference between the samples and the chosen references, using unstructured scales, followed by the verbal description of the sensory characteristics perceived in each sample evaluated. The samples were described for 30 attributes related to visual appearance, aroma, flavor, texture and hedonic terms. The method presented a good discriminative capacity, since it was able to differentiate the samples according to the PQC classification. In addition it allowed to identify the main sensory characteristics responsible for similarities and differences between the samples. The results indicate that consumers were able to infer about a quality classification based on their own perception and vocabulary, and the Brazilian traditional coffee was considered inferior to specialty coffees increasingly available in the market
EFFECT OF BIOSTIMULANT AND MICRONUTRIENT ON EMERGENCE, GROWTH AND QUALITY OF ARABICA COFFEE SEEDLINGS
Get PDFThe micronutrients and biostimulant use can promote root, shoot and seedling growth. The aim of this work was evaluated the micronutrients and biostimulant application effects on arabica coffee seedling development. The experimental design was a randomized block in factorial 5 x 3, with four replicates. Five cultivars of arabica coffee (Topázio, Catuaí Amarelo, Catuaí Vermelho 99, Catuaí Vermelho 144 and Catiguá) cultivated in green house, combined with biostimulant (Stimulate®), of micronutrients (Mo+Co) and control. 150 days after sowing the plants was evaluated. The higher seed germination velocity (0.10) was obtained with micronutrients and biostimulant. The higher height of plant, 8.88 cm, was attained with biostimulant on Catuaí Amarelo. Catuaí Amarelo and Vermelho obtained higher number of leaves (4.5) with biostimulant use and the Catuaí Amarelo (4.38) with micronutrients use. In Catuaí Amarelo was attained higher shoot dry mass and leaf area with biostimulant use, reach 1.69 g and 19.55 cm2, respectively. The higher root dry mass values (0.76 g) and Dickson quality index (0.47 and 0.48) was attained with micronutrients use to the Catuaí Amarelo e vermelho cultivars. Seedling development of Catuaí Amarelo was benefited with Stimulate® application and the cultivar Topázio did not get positive development with Stimulate® and micronutrients application
NITROGEN FERTILIZERS AND OCCURRENCE OF Leucoptera coffeella (Guérin-Mèneville & Perrottet) IN TRANSPLANTED COFFEE SEEDLINGS
Get PDFThe coffee leaf-miner (CLM) Leucoptera coffeella (Lepidoptera: Lyonetiidae) is one of the main pests of coffee plants in Brazil. Its occurrence in the crop is directly related to the physiological state and growth characteristics of coffee plants, in turn related to plant nutrition. The present work, therefore, aimed to evaluate the effect of nitrogen sources on the occurrence of CLM in coffee seedlings. The fertilizers used were ammonium sulfate, urea, and organomineral. The number of leaves mined by CLM and the relative contents of chlorophyll and crude protein in the leaves were recorded. Ammonium sulfate and urea favored higher occurrence of leaves mined and organomineral fertilizer provided the lowest incidence of leaves mined by CLM. The three sources of nitrogen increased the chlorophyll content, but only ammonium sulfate caused an increased percentage of crude protein in the leaves of coffee seedlings. For the improvement of management strategies for L. coffeella it is fundamental to understand favorable conditions, nutritional management it is one of the pest control mechanisms, thus making it possible to control the insect and prevent the population of CLM from reaching an economic damage threshold