Coffee Science (E-Journal)
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MODELS GENERATED IN NEUTRON PROBE CALIBRATION IN LATOSOL CULTIVATED WITH COFFEE AND SIGNALGRASS
Get PDFABSTRACT: The sustainability of agricultural production can be improved through the use of cover crops. The objective of this study was to evaluate the Model Identity Method in the verification of equality of linear regressions resulting from the calibration of a neutron probe for different layers, as a function of signalgrass management as a cover crop between rows of soil coffee crop in the Brazilian Central Cerrado. Aluminum tubes were installed to access the probe and two saturation basins were built in a coffee area, irrigated by a central pivot, in an Oxisol, with two management systems, T (Traditional with bare soil) and B (Signalgrass in the row). Samples were taken at depths of 0-0.20; 0.20-0.40; 0.40-0.60; and 0.60-0.80 m for the determination of physical and water properties and monitoring of soil drying; concomitant measurements were taken with the neutron probe in these layers. Two calibration curves were constructed for each layer, which were compared by the above method. It was observed that treatment B yielded differences in soil water storage in the 0.20-0.40 m layer, differing from treatment T. The statistical method allowed the observation of equality of regressions between treatments B and T at depths 0-0.20, 0.40-0.60, and 0.60-0.80 m; it also showed the need for different regression curves per layer, besides justifying the need for neutron probe calibration for each specific local condition
NUTRIENT RELEASE FROM GREEN MANURE UNDER DIFFERENT SUN-EXPOSED FACES
Get PDFThe evaluation of the decomposition of plant residues added to the soil for green manures allows better understanding of the nutrient supply for coffee. The aim of this study was to determine the decomposition constant (κ), the halflifetime (t1/2) and the nutrient release from legumes and spontaneous plant under two environmental conditions of sun-exposure in the Zona da Mata of Minas Gerais state. The experimental unit located in Araponga has northwest sun-exposure face and the experimental unit located in Pedra Dourada has the south sun-exposure face. The experimental design was a randomized block in a 2 x 8 x 6 factorial (two environments facing sun-exposure, 8 green manures and 6 residue decomposition assessment times), with four replicates. The results showed that κ and t1/2 of the evaluated green manures did not differ between the northwestern face (highest altitude, temperature and incident light) and the south face (lower altitude, temperature and incident light). The κ difference obtained between all green manures was due to its chemical and biochemical composition. At the end of the evaluation period of 240 days an average of 62,3 and 63,1% N; 99,4 and 99,5% P and 92,8 and 93,3% K were released from the green manures of the northwest and south faces respectively. The most promising legume in the total nutrients release on the northwest face was D. lablab with 74,6; 10,9 and 69,0 kg ha-1 of N, P and K, respectively. To the south face the most promising legume was C. spectabilis with 69,1; 10,4 and 47,9 kg ha-1 of N, P and K, respectively
ADAPTATION OF PROGENIES/CULTIVARS OF ARABICA COFFEE (Coffea arabica L.) IN MOUNTAINOUS EDAFOCLIMATIC CONDITIONS
Get PDFBrazil is known for production and worldwide export of coffees. Study of adaptation of new progenies/cultivars of Arabica coffee (C. arabica L.) with resistance to rust in mountainous edaphoclimatic conditions is important for crop renewal and also for new plantations. This study was performed in the mountainous region of the Espírito Santo state, Brazil, with 30 progenies/cultivars of Arabica coffee planted at 2.5 x 0.7 m spacing with four replicates and seven plants/plot. The objective of the study was to evaluate the adaptation of rust-resistance coffee genotypes and compare them with the standard cultivars (Yellow and Red Catuaís), with regards to the characteristics of productivity, rust infection, productivity, sieve, aspect, plant vigor and yield according to the different maturity periods of the fruits. The results show that there are progenies/cultivars available with yields superior to Red and Yellow Catuais for the five different maturation periods. The progenies/cultivars present tolerance/resistance to rust, high plant vigor and good agronomic characteristics of the beans. These are options for new plantations or for renovation of crops for high harvest yield and do not required the use of pesticides
CHARACTERIZATION OF BEVERAGE QUALITY IN Coffea canephora Pierre ex A. Froehner
Get PDFDifferentiation of coffee according to its quality can result in added value. Both the coffee genotype and the environment influence beverage quality. The main species grown in the Amazon region is C. canephora, which includes two distinct botanical varieties: Conilon and Robusta. The aim of this study was to characterize beverage quality in C. canephora and distinguish the Conilon and Robusta botanical varieties and intervarietal hybrids. We evaluated the beverage quality of 130 superior clones from samples of hulled coffee collected in the experimental field of Embrapa Rondônia in the municipality of Ouro Preto do Oeste, RO, Brazil. The beverage was classified according to the Robusta Cupping Protocols, which also considers the nuances of the beverage, described as neutral, fruit-like, exotic, refined, and mild. The final mean values classified the Robusta botanical variety and the intervarietal hybrids as coffees with a premium beverage, and the Conilon botanical variety as usual good quality. The nuances of the Conilon botanical variety were found to be predominantly neutral (78%), as compared to the Robusta botanical variety and the intervarietal hybrids, which exhibited 50% and 44% of their beverages, respectively, with fruit-like, exotic, or mild nuances. The genetic parameters indicate that the genetic component was more important than the environmental in expression of coffee quality attributes. Genetic variability was observed in the population evaluated, except for the Uniform Cup and Clean Cup beverage attributes
SENSORY ANALYSIS OF COFFEE DRIED WITH AND WITHOUT STIRRING
Get PDFThe production of quality coffees, with different sensory characteristics, is strongly related to drying techniques. Experiments were carried out on coffee fruits, with the presence and absence of the fruit turnover process during drying in the yard, Catuaí Vermelho 144 coffee fruits, from the Cerrado Mineiro, processed dry and wet. The treatments consisted of natural parchment, natural green, peeled parchment and demucilated parchment fruits, which were dried in a concrete yard. They were conducted in a completely randomized design, with 4 post-harvest processes, 2 types of drying (with or without tillage) and 3 replications, totaling 24 plots. Natural green and natural parchment coffees were more responsive in the final scores, when not stirred during the drying process in the yard, unlike the coffees obtained by wet processing. Peeled coffees obtained the highest scores for the attributes, regardless of the adoption or not of stirring during the drying process in the yard. It was possible to obtain scores above 80 points by the SCA protocol, without stirring the coffee in the yard
PERFORMANCE OF DIFFERENT FERMENTATION METHODS AND THE EFFECT ON COFFEE QUALITY (Coffea arabica L.)
Get PDFFermentation of coffee mucilage is a spontaneous process caused by microorganisms growing in the environment, which is influenced by factors such as the variety, climate and fruit maturity. These external factors play an important role in fermentation evolution because they have effect on the microorganism activity and the substrate transformation time. The objective in this research was to evaluate the effect of different fermentation wet process and evaluated their effect on coffee quality (Coffea arabica L.), as well as on organic acid concentrations and volatile organic compounds content, in the green coffee beans. The study was divided in two phases, one in which the pulping time was delayed and the fermentation methods were modified, and the second phase in which a bioreactor was used to control the pH and temperature of the coffee mass during fermentation. Two control treatments were used: without fermentation (mechanical removal of mucilage) and the traditional fermentation done in the farm. Significant differences in coffee quality were observed. The best quality was obtained from the treatments that used short process times and low temperatures. The concentrations of acetic, lactic and citric acids between the treatments and the control treatments were different. Higher contents of esters and ketones were found in the coffee that obtained the highest quality. The assessed processes lead to the conclusions that it is possible to improve coffee quality throughout introducing changes in the fermentation process, as well as modulating the acidity and fragrance of the final product
COFFEE LEAF MINER INCIDENCE AND ITS PREDATION BY WASP IN COFFEE INTERCROPPED WITH RUBBER TREES
Get PDFThe coffee leaf miner (CLM) Leucoptera coffeella has a wide distribution and causes significant losses in coffee plantations (Coffea spp.) in Brazil. Its occurrence can be mitigated in intercropped systems, with the rubber tree (Hevea brasiliensis) adapting well to the consortium, while also providing extra income to the producer. We aimed to determine whether the afforestation influences the microclimate and affects the leaf miner incidence and its predation by wasp in coffee plants intercropped with rubber trees. The study was undertaken in state of Paraná, Brazil, using coffee plants intercropped with rubber trees planted in double rows (alleys) spaced at 13, 16 and 22 m between alleys, and compared to sole cropping coffee plots. From January 2008 to November 2010, the presence of CLM’s lesions including those with signs of wasp predation was monitored in coffee plants intercropped with rubber trees and in the non-consorted coffee. A higher CLM’s incidence was verified in monoculture coffee plots, while coffee plants located under and two meters away from rubber trees had the lowest incidences. CLM’s incidence in intercropping system got higher as it increased distance from the trees. The number of lesions with signs of predation by wasps was positively correlated with the number CLM’s lesions, indicating a density-dependent predator-prey relationship. The coffee plants intercropped with alley rubber trees reduce the CLM’s occurrence and can be a management’s tactic for this economically important pest
INITIAL PRODUCTIVE PERFORMANCE OF COFFEE PROGENIES IN AN AREA INFESTED BY Meloidogyne paranaensis
Get PDFMeloidogyne paranaensis tem causado prejuízos aos cafeicultores brasileiros devido à destruição do sistema radicular do cafeeiro, causando a morte das plantas. A resistência genética é a medida mais econômica e ambientalmente segura para o controle desse parasita. Objetivou-se, neste trabalho, realizar a seleção de progênies de Coffea arabica resistentes ao Meloidogyne paranaensis e com características agronômicas desejáveis para renovação das lavouras em áreas infestadas. O experimento foi instalado na Fazenda São Judas Tadeu situada no Município de Piumhi - MG. Vinte e uma progênies de cafeeiro em geração F5 e cinco cultivares comerciais (testemunhas) foram avaliadas por meio da população de Meloidogyne paranaensis, produtividade de um biênio (sc.ha-1), vigor vegetativo, ciclo de maturação, uniformidade de maturação, classificação do café por tamanho do grão (peneira 17 e acima) e classificação do café moca. As progênies MG 0179-3-R1-151 e MG 0185-2-R2-132 apresentaram resistência a Meloidogyne paranaensis e boas características agronômicas em área naturalmente infestada por esse nematoide, sendo indicadas para plantios nessa situação. Nove progênies apresentaram características de tolerância ao M. paranaensis
ROOT-KNOT AND LESION NEMATODES IN COFFEE SEEDLINGS PRODUCED IN THE STATE OF MINAS GERAIS, BRAZIL
Get PDFUnderstanding the mechanisms of plant-parasitic nematodes (PPN) dispersion is vital to improve control strategies aiming to restrict dissemination of these plant parasites. In the present work, we evaluated the presence of PPN in Arabic coffee (Coffea arabica) seedlings produced in commercial nurseries in Minas Gerais, state, Brazil. A total of 2830 samples obtained from 318 coffee nurseries, in 84 counties within the South and Zona da Mata regions in Minas Gerais, Brazil and representing more than 62 million coffee seedlings, were analyzed. Meloidogyne spp. was identified in 11 samples from four counties. Pratylenchus spp. and Rotylenchulus reniformis were detected in 281 and 47 samples, respectively. According to the Regulatory Instruction N° 35 from the Ministry of Agriculture, Livestock and Food Supply (MAPA), in Brazil, coffee seedlings infected by Meloidogyne spp. are prohibited for commercialization and/or planting. However, such restrictions do not apply to other PPN. Therefore, seedlings sold in Minas Gerais may constitute sources of dissemination for root-lesion nematodes (Pratylenchus spp.) and the reniform nematode (R. reniformis)
CONDUCTIVITY TO RUST IN COFFEE UNDER DIFFERENT WOODEN AND FRUIT TREE INTERCROPPING SYSTEMS
Get PDFThe coffee intercropping with fruit and wooden species of economic value has been presented as a viable alternative for coffee cultivation in order to mitigate adverse environmental conditions for coffee trees, among other factors. Adapting the crop management to the new conditions stablished by the system is fundamental to obtain success on intercropping. One of the most serious diseases for the crop is the rust caused by Hemileia vastatrix., which may have its severity increased in function of the microclimate conditions provided by the trees. In this sense, the disease behavior under different intercropping systems and consequent different need to adapt the control measures when compared to the cultivation in full sun should be investigated. The present study was conducted aimed to verify the impact of tree systems composed by three wooden species, Cedar (Acrocarpos fraxinifolius), African mahogany (Khaya ivorensis ), Teak (Tectona grandis ) and two species of fruit trees, avocado (Persea Americana) and macadamia (Macadamia integrifolia) planted in different spacing over the occurrence and evolution of rust.It was possible to observe that coffee rust began to progress in the coffee plants from the month of February reaching a peak in September in all the treatments. Differences were observed in the progress curves of the disease, especially in the species that presented larger canopy such as avocado. Further studies are suggested with the purpose of establishing the microclimatic changes provided by the cultivation of different wooden and fruit species in intercropping with coffee, according to the dynamics of the climate and their development