Biblioteca do Café
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Item Varietal identification of coffee seeds by RAPD technique(Instituto de Tecnologia do Paraná - Tecpar, 2004-07) Crochemore, Maria Lúcia; Nunes, Liliane Moreira; Andrade, Giselly Aparecida; Molinari, Hugo Bruno Correa; Vasconcellos, Maria ElizabethThis study aimed the identification of cultivars and/or lines of Coffea arabica of commercial interest, using PCR-RAPD markers. The DNA of ground seeds lots of 12 cultivars and/or lines were evaluated with five primers (Operon OPA 01, OPA 04, OPG 11, OPY 16, and OPX 09) were obtained from a selection of 56 primers. The electrophoretic profiles allowed distinction among eight cultivars and/or lines as well as heterogeneity between and within lots of IAPAR59.Item New and efficient AS-PCR molecular marker for selection of coffee resistant to coffee leaf rust(Crop Breeding and Applied Biotechnology, 2024-10-15) Almeida, Dênia Pires de; Carneiro, Deisy Guimarães; Caixeta, Eveline Teixeira; Alves, Danúbia Rodrigues; Zambolim, LaércioCoffee leaf rust, caused by Hemileia vastatrix, is the most important disease affecting Coffea arabica. The use of molecular markers through marker-assisted selection (MAS) is an effective approach to develop cultivars with multiple and durable resistance, which is economically and environmentally beneficial for this disease control. In this work, a new molecular marker based on allele-specific polymerase chain reaction (AS-PCR) associated with the quantitative trait locus (QTL) of the linkage group 5 (LG5), which confers resistance to races I, II and pathotype 001 of H. vastatrix, was developed. The CaRHv10-AS marker was validated in a segregating genetic mapping population of 247 F2 genotypes and demonstrated selection efficiency greater than 97% for genotypes with resistance to three races. Thus, this work provides a fast, robust, and affordable molecular marker for use in MAS, facilitating the development of coffee plants with multiple resistance and ensuring sustainable coffee production.Item Multispectral images for discrimination of sources and doses of fertilizer in coffee plants(Universidade Federal de Viçosa, 2023-06-16) Rezende, Camila Isabel Pereira; Assis, Gleice Aparecida de; Martins, George Deroco; Carvalho, Fábio Janoni; Franco, Miguel Henrique Rosa; Araújo, Nathalia Oliveira deRemote monitoring of the management of coffee crops is necessary as the demand in decision-making, where the aim is to rise production based on sustainable management is in a constant growth. In this work, it was evaluated the potential of images obtained by low-cost sensors in the discrimination of sources and doses of mineral and organomineral fertilizers in coffee. The experimental design was in randomized blocks, with five blocks and six treatments, as follows: (T1) - 100% of the organomineral treatment; (T2) - 70% of the organomineral treatment; (T3) - 50% of the organomineral treatment; (T4) - 100% of mineral fertilization; (T5) - standard treatment of the farm and (T6) - 70% of mineral fertilization. After management, we used the Mapir 3 Survey3W camera coupled to an ARP drone – Phantom4 to take images of the experiment over a 12-month vegetative period. Combined with image taking, it was collected agronomic parameters of coffee growth and productivity for two crops and concluded that different fertilization doses did not significantly affect the analyzed parameters. Based on the supervised classification of multispectral images, it was possible to discriminate treatments with a higher degree of accuracy (86.66% accuracy) than when analyzing coffee growth parameters.Item Agronomic performance and productivity of Arabica coffee intercropped with timber species(Universidade Federal de Viçosa, 2023-04-14) Freitas, Ana Flávia de; Fonseca, Arley José; Volpato, Margarete Marin Lordelo; Carvalho, Gladyston Rodrigues; Venturin, Regis Pereira; Silva, Vânia AparecidaThe insertion of the tree component in coffee production is a strategy from an economic and environmental perspective. Thus, the objective of this study was to evaluate the temporal influence on the agronomic and productive performance of the coffee crop under the interference of different tree species as a function of spacing. The experiment was set in the municipality of Santo Antônio de Amparo-MG, in 2012, and conducted in a randomized block design with four replications. The treatments were: cultivar ‘Catuai Vermelho IAC 99’ in monoculture (3.40 m x 0.65 m) and intercropped with African mahogany, teak and pink cedar, in two spacings (9 x 13.6 m and 18 x 13.6 m), in coffee rows. Three coffee rows were fixed between rows, totaling 13.6 m. The following variables were evaluated: height (m), stem diameter (cm), crown diameter (m), productivity (bags ha-1) and yield (l/sc) for coffee. From the evaluations, there is a significant effect of height, productivity and yield for the coffee crop. The system intercropped with tree species did not influence coffee productivity and yield until the 3rd harvest and, for the 5th harvest, intercropping with mahogany favored productivity, although the accumulated productivity did not show any treatment effect.Item Exploring drought tolerance in coffee: a physiological approach with some insights for plant breeding(Brazilian Journal of Plant Physiology, 2004-06) DaMatta, Fábio MuriloThis paper briefly reviews some selected traits (leaf area, crown architecture, water-use efficiency and carbon isotope discrimination, water relations and root characteristics), which may be explored in breeding programmes to tolerance to drought stress in arabica and robusta coffee.Item Effects of different drying rates on the physiological quality of Coffea canephora Pierre seeds(Brazilian Journal of Plant Physiology, 2005-06) Rosa, Sttela Dellyzete Veiga Franco da; Brandão Júnior, Delacyr da Silva; Pinho, Édila Vilela de Resende Von; Veiga, André Delly; Silva, Luiz Hildebrando de Castro eDesiccation tolerance in seeds depends on the species, development stage and drying conditions, especially the water removal rate. Coffea seeds are considered of intermediate performance, because they tolerate relative dehydration compared to orthodox seeds and are sensitive to low temperatures. The objective of this study was to verify the effect of different drying rates on the viability and storability of Coffea canephora seeds. A complete randomized experimental design was used, in a factorial 3 x 5 x 2 design, with three drying rates (fast, intermediate and slow), five final mean water contents after drying (51, 42, 33, 22 and 15 %) and two storage temperatures (10 and 20°C). The germination and seed vigor assessments, using radicle protrusion, cotyledon leaf opening, seedling emergence and emergence speed index, were performed shortly after drying and after two and four months storage. It was observed that with reduction in the water content there was reduction in the germination values and seed vigor, for all the drying rates. The greatest reductions in physiological quality occurred when the seeds were dried quickly and the best results were obtained at the intermediate drying rate. There was an effect of drying rate and storage temperature on the physiological quality of the seeds, and lower germination and vigor values were observed in seeds with lower water content stored at 20°C. C. canephora seeds were tolerant to desiccation down to 15 % water content and can be stored for four months at 10°C. A temperature of 20ºC can be used to store C. canephora seeds, as long as the water content is not reduced to values below 22 % water content.Item Períodos de interferência de Commelina benghalensis na cultura do café recém-plantada(Sociedade Brasileira da Ciência das Plantas Daninhas, 2005-09) Dias, T. C. S.; Alves, P. L. C. A.; Lemes, L. N.A presente pesquisa teve por objetivo avaliar os períodos de interferência de Commelina benghalensis sobre o crescimento inicial de mudas de Coffea arabica, sob condições de inverno e verão. Para isso, mudas de café e, posteriormente, de trapoeraba foram transplantadas para caixas de cimento-amianto com capacidade de 70 L, utilizando solo como substrato. Os períodos de convivência ou controle foram de 0-15, 0-30, 0-45, 0-60, 075 e 0-90 dias após o plantio do cafeeiro, totalizando 12 tratamentos, dispostos em blocos casualizados, em quatro repetições. Ao término de cada período, avaliaram-se algumas características de crescimento das plantas. As características do cafeeiro mais afetadas pela trapoeraba foram a área foliar e a biomassa seca de folhas das mudas de café, sendo essas as únicas características que apresentaram reduções significativas no verão. No inverno, o número de folhas e a biomassa seca do caule também tiveram reduções significativas. Os períodos críticos de prevenção da interferência foram de 15 a 88 e 22 a 38 dias após o plantio das mudas de café, para condições de inverno e verão, respectivamente.Item Induction and differentiation of reproductive buds in Coffea arabica L.(Brazilian Journal of Plant Physiology, 2005-06) Majerowicz, Nidia; Söndahl, Maro R.The induction and differentiation phases of reproductive buds of Coffea arabica L. have not received much attention. In the present paper, axillary buds from five plagiotropic branches that developed in the same growing season without fruits (1st crop branches), and from green segments of five recently grown plagiotropic branches with fruits (2nd crop branches), were collected every two weeks during successive inductive months of the year. This study was carried out with adult arabica trees, Catuaí Vermelho cv. IAC 81, cultivated under normal farming conditions in the region of Campinas, SP, Brazil (22º54' Lat. S). Slides of longitudinal-axial sections of 10-12 mum thickness were mounted for the characterization and quantification of histological stages of bud differentiation. The results indicate that the regulatory signals controlling the phases of induction and differentiation of floral buds are distinct, and that there are differences in the response between branches with and without fruits. In the case of 1st crop branches (no fruits present), induction of floral buds took place in January and February, whereas floral bud differentiation was observed during the months of March and April. In 2nd crop branches (fruits present), the induction of floral buds was observed during any month of the year provided that they had already overcome their juvenile state (October-July, in this study). In these 2nd crop branches, the flower bud differentiation was only observed after harvesting all pre-existing fruits of each branch (after May, in this study), which suggests that floral bud differentiation in Arabica coffee is influenced by the source-sink relationship, i.e. by the presence of developing fruits within each plagiotropic branch.Item Ethylene production and acc oxidase gene expression during fruit ripening of Coffea arabica L.(Brazilian Journal of Plant Physiology, 2005-09) Pereira, Luiz Filipe Protasio; Galvão, Rafaelo M.; Kobayashi, Adilson K.; Cação, Sandra Maria B.; Vieira, Luiz Gonzaga EstevesThe phytohormone ethylene is involved in several physiological and developmental processes in higher plants, including ripening of fruits, abscission of organs and tissues, senescence, wound response as well as in other abiotic stresses. The enzyme 1-aminocyclopropane-1-carboxylate oxidase (ACO) catalyzes the last step of ethylene biosynthesis. The production of ethylene and the expression of a Coffea arabica ACO gene during the last stages of fruit maturation were investigated. A rapid increase of ethylene production at the green-yellow stage of fruit ripening, after the end of endosperm formation, and a decrease of ethylene production at the cherry stage indicates a climacteric phase during ripening. An ACC oxidase (Ca-ACO) from coffee fruit cDNA was cloned and characterized using primers previously reported. The cDNA is homologous to previously described ACC oxidase cDNA in Coffea. The nucleotide and amino acid deduced sequences of the clone showed high homology with ACO from climacteric fruits. Northern blots were performed to determine the Ca-ACO transcription pattern from different tissues and from fruits at different ripening stages. Coffee fruits at an early ripening stage (green) showed the lowest level of Ca-ACO transcript accumulation. The transcript levels of Ca-ACO did not change significantly during the later stages, suggesting the presence of post- transcriptional control mechanisms. These results, taken together, strongly suggest a climacteric nature of coffee fruit ripening.Item Coffee leaf miner resistance(Brazilian Journal of Plant Physiology, 2006-06) Guerreiro Filho, OliveiroThe coffee leaf miner, Leucoptera coffeella, is a common pest of coffee plantations in Brazil. Though it is effective, chemical control substantially increases the cost of production and constitutes a significant risk for the environment. Resistant coffee cultivars have been and continue being developed through classic and molecular selection techniques. Basic knowledge about the biology of this insect, the damage it causes to the plants, the identification of sources of resistance, the development of efficient selection methods and knowledge about the genetics of resistance have contributed to the efficiency of the ongoing genetic improvement programs. Recently, coffee genomics studies have also promoted an improvement in the efficiency of the development of cultivars resistant to this insect. We present a short review of each of these aspects of the search for resistance.