Biblioteca do Café

URI permanente desta seçãohttps://sbicafe.ufv.br/handle/123456789/1

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Agora exibindo 1 - 10 de 115
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    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 Esteves
    The 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.
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    Coffee seed physiology
    (Brazilian Journal of Plant Physiology, 2006-06) Eira, Mirian T. S.; Silva, E. A. Amaral da; Castro, Renato D. De; Dussert, Stéphane; Walters, Christina; Bewley, J. Derek; Hilhorst, Henk W. M.
    Considerable advances in our understanding of coffee seed physiology have been made in recent years. However, despite intense research efforts, there are many aspects that remain unclear. This paper gives an overview of the current understanding of the more important features concerning coffee seed physiology, and provides information on recent findings on seed development, germination, storage and longevity.
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    Coffee biotechnology
    (Brazilian Journal of Plant Physiology, 2006-06-14) Santos-Briones, César De Los; Hernández-Sotomayor, S. M. Teresa
    In the last three decades, interest has turned to in vitro cell culture in different areas of coffee research. In vitro techniques have been applied not only for coffee improvement through genetic transformation but also to study various aspects in coffee cells such as chemical (caffeine synthesis and the production of coffee aroma), physiological and more recently, biochemical aspects. The most important advances obtained to date on in vitro coffee techniques in fields like biochemistry, physiology, regeneration systems and genetic engineering, are presented and discussed.
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    Partitioning of nitrate reductase activity in Coffea arabica L. and its relation to carbon assimilation under different irradiance regimes
    (Brazilian Journal of Plant Physiology, 2007-03-26) Carelli, Maria Luiza C.; Fahl, Joel I.
    The distribution of in vivo nitrate reductase (EC 1.6.6.1) activity (NRA) between leaves and roots was studied in young coffee plants (Coffea arabica L.) grown in pots with watered sand in a glasshouse and irrigated with nutrient solution. The influence of irradiance regimes on the partitioning of NRA, and its relation with CO2 assimilation, was also evaluated in plants grown under approximately 20, 50 and 100% of full sunlight. Time-course of nitrate accumulation in nitrogen-starved plants showed a similar pattern in leaves and roots after supplying 15 mmol L-1 nitrate, indicating efficient ability of the roots to export nitrate to the shoot. At the same time, NRA was rapidly induced in both tissues. In shoots, NRA partitioning was synchronized among the various leaf pairs. The initial increase in NRA, as each leaf pair emerged, coincided with the optimum NRA values of the next older leaf pair. However, the average shoot NRA remained relatively constant for each sampling date. During the first 23 weeks of vegetative growth, the mean NRA was 32% higher in leaves than in roots. The irradiance regimes influenced the partitioning of NRA between leaves and roots. The NRA leaf /root ratio was 0.72, 1.21 and 1.05, respectively, for plants grown under 20%, 50% and 100% of full sunlight. Leaf NRA was positively correlated with CO2 assimilation, in response to irradiance regimes. Under favorable CO2 assimilation conditions, higher NRA was observed in leaves than in roots, and the contrary trend occurred under limiting CO2 assimilation conditions. Under moderate irradiance regime the leaves were the main site of nitrate reduction, contributing with 70% of the whole plant nitrate assimilation.
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    Antifungal compounds as a mechanism to control Hemileia vastatrix by antagonistic bacteria
    (Sociedade Brasileira de Fitopatologia, 2013-10-29) Haddad, Fernando; Saraiva, Rodrigo M.; Mizubuti, Eduardo S. G.; Romeiro, Reginaldo S.; Maffia, Luiz A.
    Pseudomonas putida P286 and Bacillus thuringiensis B157 controlled coffee rust under greenhouse and field conditions. Now we studied the mechanism(s) of antagonism of both bacteria to Hemileia vastatrix. Bacterial effects on urediniospore germination and disease severity were evaluated in experiments with six treatments: (i) growth broth, (ii) supernatant centrifugation, (iii) bacterial cell centrifugation and re-suspension, (iv) UV inactivation of the bacteria, (v) 523 medium, and (vi) saline solution. The treatments i to iii reduced both spore germination and disease severity. Each isolate was applied at different concentrations and time periods before inoculation of H. vastatrix. The efficiency in controlling rust was reduced at the lowest concentrations and at the largest intervals between applications. In spatial separation experiments, both bacteria did not induce systemic protection, whereas protected locally the coffee plants against H. vastatrix. Therefore, the mechanism of both isolates against H. vastatrix is attributed to the production of antifungal compound (s).
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    Alterations in leaf anatomy and physiology caused by the red mite (Oligonychus ilicis) in plants of Coffea arabica
    (Brazilian Journal of Plant Physiology, 2007-06-15) Fahl, Joel I.; Queiroz-Voltan, Rachel B.; Carelli, Maria Luiza C.; Schiavinato, Marlene A.; Prado, Ana K. S.; Souza, Júlio C.
    Three degrees of red mite infestation (Oligonychus ilicis McGregor) (Acari: Tetranychidae) were evaluated with regard to leaf anatomy, photosynthetic gas exchange and leaf ethylene production, in a commercial crop of approximately 12-year-old trees of Coffea arabica 'Catuaí Vermelho'. As a complementary study, foliar anatomy was also evaluated in a recuperated crop of C. arabica 'Mundo Novo' that had presented a high degree of red mite infestation during the dry period of the prior growing season. The red mite-infested leaves were bronze-coloured, with intensity proportional to the degree of internal damage. On feeding, the red mite introduces its stylet in the adaxial epidermis and, as a result, chloroplasts are destroyed in the feeding area. The number of chlorophyll-free cells in the palisade parenchyma was proportional to the intensity of attack by red mites. The cells of the spongy parenchyma, localized below the feeding areas of the mites, did not show any alterations, having intact chloroplasts, with the exception of some leaves that suffered from intense attack. Net photosynthesis rate declined, but only in leaves under intense red mite attack, due to destruction of chloroplasts in the attacked cells. Nevertheless, transpiration and stomatal conductance were unaffected by red mite. The concentrations of ethylene produced by the leaves were similar regardless of three levels of attack, suggesting that red mite infestation does not lead to leaf abscission. In addition, anatomical studies of 'Mundo Novo' leaves of plants that visually recovered from red mite attack showed that, even with scars present, they continued attached on the plant.
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    Incidence and distribution of filamentous fungi during fermentation, drying and storage of coffee (Coffea arabica L.) beans
    (Sociedade Brasileira de Microbiologia, 2008-10-02) Silva, Cristina Ferreira; Batista, Luis Roberto; Schwan, Rosane Freitas
    The objective of this work was to isolate and characterize filamentous fungi present in different stages of harvest, fermentation, drying and storage of coffee beans processed by natural method. The cherries were hand-picked and then placed on a cement drying platform where they remained until reached 11% of humidity. Microbial counts were found in all samples during fermentation and drying of the coffee beans. Counts of fungi in the coffee cherries collected from the tree (time 0) were around 1.5 x 10³ CFU/g. This number increased slowly during the fermentation and drying reaching values of 2 x 10(5) CFU/g within 22 days of processing. Two hundred and sixty three isolates of filamentous fungi were identified. The distribution of species during fermentation and drying was very varied while there was a predominance of Aspergillus species during storage period. The genera found were Pestalotia (4), Paecelomyces (4), Cladosporium (26), Fusarium (34), Penicillium (81) and Aspergillus (112) and comprised 38 different species.
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    Coffea arabica L: History, phenology and climatic aptitude of the state of São Paulo, Brazil
    (Instituto Biológico, 2021-12-17) Torres, Guilherme Almussa Leite; Campos, Cleide Nascimento; Salomon, Marcus Vinicius; Pantano, Angélica Prela; Almeida, Julieta Andrea Silva de
    The genus Coffea belongs to the Rubiaceae family and includes two species with optimum economic performances, Coffea arabica and Coffea canephora. The state of São Paulo is one of the states that produce the species C. arabica in Brazil. Arabica coffee has been of great importance to São Paulo, providing relevant contributions to the historical, political, architectural, gastronomic, touristic, artistic, agricultural, industrial and social sectors since its introduction into the state in the nineteenth century. The agricultural sector includes crops produced by both small farmers and by highly technological agricultural groups. Coffea arabica plants present six phenological phases, all sensitive to changes in temperature and rainfall. In the reproductive phases, the species requires short days, low temperatures and no rainfall, followed by the rainy season. However, the phenological phases of the coffee plants can be harmed or even inhibited by dry or rainy seasons that are too long or too short. In the state of São Paulo, the municipalities of Garça and Franca show optimal coffee productivity, whereas those of Adamantina and Registro are low, and the agricultural aptitudes of these four municipalities show strong relationships with their geographical distributions in the state. Garça and Franca are situated in areas where the predominant dry and rainy seasons favor the occurrence of the phenological phases of arabica coffee plants, whereas Adamantina and Registro are located in areas with long dry and rainy seasons, respectively, characteristics that harm the development of the reproductive phenological phases of this culture.
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    European strategic trade policy and Brazilian export growth during the nineteenth century
    (Departamento de Economia da Faculdade de Economia, Administração e Contabilidade da Universidade de São Paulo (FEA-USP), 2022-04-04) Absell, Christopher David
    Until the Amazonian rubber boom, cane sugar and coffee were the two most important export commodities for Brazil during the nineteenth century. Despite inherent differences in methods of cultivation, both sugar and coffee at once benefitted and suffered from the characteristics of Brazil’s factor endowment in land, labour and capital. Yet these two export commodities demonstrated divergent growth patterns across the nineteenth century. The difference was not one of relative productivity and thus price competitiveness disadvantage, but of the imperfectly competitive nature of the international market for each commodity. European governments actively practised strategic trade policy to transfer profits from foreign to domestic or colonial firms. These market distortions were exogenous, imposed by consumer markets, and took the form of European colonial tariff preferences and subsidies to domestic production. Coffee suffered less from imperfect competition, thus remaining more profitable to Brazilian agricultural producers in the long run.
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    Leaf extract of Coffea arabica L. reduces lipid peroxidation and has anti-platelet effect in a rat dyslipidemia model
    (Faculdade de Ciências Farmacêuticas da Universidade de São Paulo, 2022-09-02) Simões, Mario Henrique Souza; Salles, Bruno Cesar Correa; Duarte, Stella Maris da Silveira; Silva, Marcelo Aparecido da; Viana, André Luiz Machado; Moraes, Gabriel de Oliveira Isaac de; Figueiredo, Sonia Aparecida; Ferreira, Eric Batista; Rodrigues, Maria Rita; Paula, Fernanda Borges de Araújo
    This study aimed to evaluate the antioxidant potential of the Coffea arabica Lineu (L.) leaf extract and its effects on platelet aggregation of dyslipidemic rats. The extract was obtained by the percolation of C. arabica L. leaves in hydroethanolic solution 70% (v/v). The mass spectrometry FIA-ESI-MS² suggested the presence of chlorogenic acid, rutin acid, and quinic acid. The DPPH• radicals scavenging capacity was demonstrated (IC50 = 0.06 mg/mL). The extract was administered to rats by gavage (300 mg/kg/day) for 56 days. Dyslipidemia was induced by administering Triton WR-1339 (300 mg/kg body weight) on the 54th day. On day 56, blood was collected by puncturing the abdominal aorta artery and the aortic artery was removed. Lipid profile, markers of renal and hepatic injury, lipid peroxidation, and platelet aggregation tests were carried out. The ingestion of extract reduced the lipid peroxidation (aorta and plasma) and platelet aggregation in dyslipidemic rats. The extract did not affect markers of renal and hepatic function as analyzed in this study, suggesting neither impaired liver nor kidney function in these animals. Therefore, our results demonstrate that the extract of leaves of C. arabica L. show antioxidant potential in vitro and in vivo as well as anti-platelet aggregation in dyslipidemic animals.