Coffee Science (E-Journal)
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Classification, physicochemical, soil fertility, and relationship to Coffee robusta yield in soil map unit selected
Get PDFThe research was aimed (1) to classify, characterize the physicochemical properties, determine the fertility of the soil, and (2) to obtain the relationship of soil fertility on the character yield for Coffee robusta in the 10 units of the soil map (SMUs) selected in Silima Pungga-Pungga Sub-district, Dairi District. This research was conducted in Silima Pungga-Pungga sub-District, Dairi District, North Sumatra Province, Indonesia with coordinates 2080’-2088’NL and 98004’-98017'EL from July 2014 until June 2017. This research was conducted by overlay the maps, classifying soil profiles, characterizing soil, soil fertility assessing, and regression analysis of soil fertility with the yield for Coffee robusta using IBM SPSS Statistics v.20 software. The result showed the ten from 18 SMUs selected for Coffee robusta in Silima Pungga-Pungga sub-District, Dairi District, and has the highest land area sequentially, such as SMU 11, 14, and 1. Based on the ten SMUs selected, found in two representative soil profiles, include the profile 1 (SMU 1, 2, 8, 9, 11, 13, 14, 16, 18) covering an area of 1,703.30 ha with the inceptisol and profile 10 (SMU 10) covering an area of 176.81 ha with the entisol. Inceptisol order has greater the soil physicochemical properties compared to entisol from ten SMUs selected for Coffee robusta. The effect of cation exchange capacity, base saturation, P-total, K-total, and C-organic have significantly increased the productivity Coffee robusta by 89.30%, however the effect was not significant to the 100 grains of dry weight.
Key words: Entisol; Coffee robusta; Inceptisol; Overlay; Soil fertility
Ultrastructural damage in coffee seeds exposed to drying and to subzero (°C) temperatures
Get PDFDuring drying and freezing, protective mechanisms act to maintain seed physiological quality. Some of these mechanisms contribute to the integrity of cell membranes. The damage caused to cell membranes due to cell stress can be seen in ultrastructural studies. The aim of this study was to investigate ultrastructural changes in endosperm cells of coffee seeds brought about by drying and by exposure to low temperatures. Seeds of Coffea arabica were dried in silica gel to moisture contents of 40, 20, and 5 % (wb) and brought to equilibrium at temperatures of 10, -20, and -86oC. Germination, vigor, and tetrazolium tests were performed for evaluation of seed physiological quality. Ultrastructural damage was analyzed by scanning electron microscopy. Coffee seeds with 40% moisture content have whole, swollen, and expanded cells, with a filled lumen and without signs of damage. The physiological and ultrastructural quality of seeds exposed to below zero temperatures with 40% moisture content is compromised. They have null germination and empty cells, indicating leakage of cell content. Drying of coffee seeds leads to uniform contraction of inner cell content. Drying of coffee seeds to 5% moisture content leads to intense contraction of cell volume, with physiological and ultrastructural damage.
Key words: Scanning electron microscopy; desiccation tolerance; Coffea arabica L
Technical and economic viability of manual harvesting coffee yield maps
Get PDFPrecision coffee growing is a concept that implies the use of precision agriculture techniques in coffee plantations. For the coffee growing, the precision electronic resources coupled to the harvesters are very scarce. Thereby, the harvest of coffee plantations that compose the grid sampling for generation of thematic maps can be performed manually. The aim of the present study was to generate a linear regression model to estimate the time required to harvest, estimate the labor costs to harvest manually the georeferenced sample points for generation of coffee yield maps. The study was performed in a coffee area of 56 hectares using two sampling points per hectare, totaling 112 points, being evaluated four coffee plants for each point. The manual harvest of the points was performed by four rural workers with experience in the coffee harvest. Afterwards, the collected volume was measured by a graduated container and the times were obtained by the digital stopwatch. Based on the data obtained in the field, a linear correlation model was established between the harvest time of each sampling point and the yield of the point, whose R² value was 78.27, cost was R$ 8.92 per point. These results are relevant for estimating the amount of labor force required to generate manually harvest yield maps according to the producer’s coffee yield estimate, contributing to the closure of the precision coffee growing cycle.
Key words: Precision agriculture; crop mapping; field efficiency; costs
Interaction between mealybugs (Pseudococcidae) and coffee plants
Get PDFMealybugs, Planococcus citri (Risso) and Planococcus minor (Maskell) (Hemiptera: Pseudococcidae) are able to colonize several plants, among them, coffee (Coffea spp.), where may impair the production of this crop. Despite this diversity of colonizing plants, frequent outbreaks of these mealybugs have been found in certain plants. In this work, we tested the hypothesis that P. citri and P. minor show a better performance, i.e., greater longevity and higher reproductive rate, as well as higher survival in a given coffee species. We studied in the laboratory the food preference of these mealybugs through a free choice test and their development and reproduction in Coffea arabica L. cv. Mundo Novo-IAC–379-19 and Coffea canephora (Pierre & Froenher) cv. Conilon 213. The responsiveness of these insects to the volatiles emitted by these coffee plants was analyzed using an olfactometer. The data showed that mealybugs preferred Conilon coffee plants over the Mundo Novo and, despite completing their development in these two coffee species, most of the biological evaluated parameters were affected by the host species. In the olfactometer assays, the volatiles emitted by the coffee plants cv. Mundo Novo and Conilon were equally attractive to these mealybugs. It is concluded that, although there is no discrimination of odors between coffee plants, Mundo Novo and Conilon, both species of mealybugs show food preference for Conilon, having their development and reproduction favored in these plants.
Key words: Coffea spp.; Food preference; Olfactory responses; Performance; White mealybug
Effect of water stress and Coffee ringspot virus on coffee leaf temperature and its relationship with Brevipalpus yothersi population
Get PDFThe mite Brevipalpus yothersi Baker 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.
Key words: Coffee ringspot; Coffea arabica; Vegetal stress; Nutrient
Motives for coffee consumption at coffee shops in Mexico
Get PDFCoffee is one of the main sources of foreign exchange for developing countries. Mexico accounts only 2.68% of the world coffee production, but represent the most important source of foreign exchange in the agricultural sector. The Mexican coffee began to be recognized in recent years, and despite the increase of the consumption, Mexico is not considered an important consumer. The objective was to analyse the motives for coffee consumption at coffee shops with quality labels. A national and a transnational company were selected in central Mexico to carry out a total of 600 questionnaires. Thequestionnaire had four sections: frequency of consumption, Food Choice Questionnaire (FCQ), some images of coffee quality labels, and a socio-economic. The data were analysed using multivariate statistics, factor and cluster analysis. Indifferent, Pragmatic and Hedonic-Dependent consumers were identified; who are mostly young and middle-aged, single, childless and college educated. Their interest in attending coffee shops is to socialize; they are not interested in quality labels which have negative implications for the use of this type of labels in Mexico.
Key words: Consumers; food choice questionnaire; factor and cluster analysis
Association of Heterorhabditis amazonensis and Beauveria bassiana aiming the control of Hypothenemus hampei
Get PDFAmong the main problems for coffee production, it is possible to mention the occurrence of coffee borer, Hypothenemus hampei. In order to seek alternatives to control the pest, the objective of this study was to evaluate the interaction between Beauveria bassiana and Heterorhabditis amazonensis MC01 on the control of coffee borer. Therefore, four experiments were set. In the first, B. bassiana, H. amazonensis MC01 and both entomopathogens associated were applied in bored fruits displaced in vermiculite. In the second experiment, the methodology was similar to the previous one; however, the fruits were immersed in the suspensions. In the third experiment was evaluated the transport of B. bassiana conidia by H. amazonensis, checking the mortality of Tenebrio molitor. In the fourth experiment, the fungus and the nematode were added to Petri dishes containing agar-water. It was found that, when entomopathogens were applied to vermiculite, treatments using B. bassiana and H. amazonensis alone caused the highest mortality of H. hampei adults. For larvae, there was no difference among treatments. The same was observed when the fruits were dipped in the suspensions, with no difference among treatments. As for T. molitor mortality, it was observed that there was no difference among treatments. However when applied in combination, there was a higher mortality caused by B. bassiana compared to H. amazonensis. In the last experiment, juveniles and conidia were found on the opposite side of the dish, and it can be inferred that the presence of conidia was due to transport by infective juveniles.
Key words: Biological control; Coffea; Entomopathogenic fungus; Entomopathogenic nematode
Physicochemical, microbiological, and sensory analysis of fermented coffee from Sierra Nevada of Santa Marta, Colombia
Get PDFThe 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 fermentationrelated 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.
Key words: Agroindustry; Coffea arabica; Coffee quality; Cup quality; Wet fermentation
Soil attributes and coffee yield in an agroforestry system
Get PDFCoffee 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 ‘Catucaí’ 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 growing under full sun. 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.
Key words: Coffea arabica; Intercropping; Shading; Soil fertility
Histochemical approach of the mobilization of reserve compounds in germinating coffee seeds
Get PDFThe endosperm of coffee beans is an important structure which is composed of different reserve compounds. In the present work, we followed anatomical features during the reserve mobilization of Coffea arabica L. ‘Catuaí’ seed samples, harvested at 20 different sites, after 0, 3, 6, 12, 24, 33 and 45 days of imbibition. Seed samples were properly fixed and stored, respectively, for histochemical and enzyme activity approach. 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 is concomitant with an increased activity of MDH is observed at the first 12 days, whereas SOD showed higher expression after 33 days of soaking. At the 33rd 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.
Key words: Coffea arabica; germination; reserve breakdown; histochemistry; seed anatomy