Biblioteca do Café
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Item Ecophysiology of coffee growth and production(Brazilian Journal of Plant Physiology, 2007-12) DaMatta, Fábio M.; Ronchi, Cláudio P.; Maestri, Moacyr; Barros, Raimundo S.After oil, coffee is the most valuable traded commodity worldwide. In this review we highlighted some aspects of coffee growth and development in addition to focusing our attention on recent advances on the (eco)physiology of production in both Coffea arabica and C. canephora, which together account for 99% of the world coffee bean production. This review is organized into sections dealing with (i) climatic factors and environmental requirements, (ii) root and shoot growth, (iii) blossoming synchronisation, fruiting and cup quality, (iv) competition between vegetative and reproductive growth and branch die-back, (v) photosynthesis and crop yield, (vi) physiological components of crop yield, (vii) shading and agroforestry systems, and (viii) high-density plantings.Item Autonomy and network modulation of photosynthesis and water relations of Coffea arabica in the field(Brazilian Journal of Plant Physiology, 2008-08-07) Camargo-Bortolin, Lívia H.G. de; Prado, Carlos H.B. A.; Souza, Gustavo M.; Novaes, PaulaThe degree of connection between leaf gas exchange and leaf water potential, and the autonomy of these variables in relation to meteorological conditions were determined in three cultivars of Coffea arabica during clear and cloudy days. High values of vapor pressure deficit, air temperature and photosynthetic photon flux density resulted in low leaf autonomy during a clear day, irrespective the degree of connection among leaf physiological variables. Tight synchronization between physiological and meteorological variables was considered one important cause of net photosynthesis (P N) decreasing during a clear day. In contrast, diurnal P N was around three times higher on a cloudy day, when all cultivars presented high autonomy. Principal component analyses corroborated autonomy results revealing unambiguous opposition between leaf physiological and meteorological vectors, besides less leaf physiological variability throughout the clear day. Despite these general responses during clear and cloudy days, there were significant differences among studied cultivars. Leaf autonomy was an important reference to evaluate C. arabica under environmental stress and should be taken into account when selecting cultivars under field conditions.Item Influência da infestação de Oligonychus ilicis (McGregor, 1917) (Acari: Tetranychidae) sobre a taxa de fotossíntese potencial de folhas de cafeeiro(Instituto Biológico, 2009) Franco, R. A.; Reis, P. R.; Zacarias, M. S.; Altoé, B. F.; Barbosa, J. P. R. A. D.Oligonychus ilicis (McGregor, 1917) é um dos principais ácaros fitófagos do cafeeiro ( Coffea spp.), embora não esteja relacionado entre as pragas primárias. Esses ácaros vivem na superfície superior das folhas e, para se alimentar, perfuram as células da epiderme e do mesófilo e absorvem o conteúdo celular extravasado. Em consequência, as folhas perdem o brilho natural e tornam-se bronzeadas. O objetivo deste trabalho foi quantificar a taxa de fotossíntese de folhas de cafeeiro apresentando diferentes níveis de infestação de O. ilicis. O estudo foi realizado em plantas de cafeeiro (Coffea arabica L., cultivar Catuaí) envasadas e com três anos de idade, mantidas em casa de vegetação. Foram realizadas infestações em cinco diferentes níveis (0, 15, 30, 60 e 120 fêmeas adultas do ácaro/folha), com ácaros provenientes da criação de manutenção, em folhas do terceiro par, a partir do ápice e totalmente expandidas, localizadas em ramos do terço médio da planta, com cinco repetições. A medição da fotossíntese potencial foi realizada por meio do oxigênio fotossintético produzido, utilizando-se de um monitor de oxigênio com eletrodo tipo Clark acoplado a uma caixa de controle de fluxo elétrico CB1. As avaliações foram realizadas 7 e 21 dias após a infestação com os ácaros, e os dados obtidos foram submetidos a uma análise de regressão. Houve correlação negativa entre os diferentes níveis de infestação e a fotossíntese potencial, sendo que, nos níveis 15, 30, 60 e 120 ácaros/folha, as taxas de fotossíntese foram reduzidas, em relação ao tratamento-testemunha, em 37,2; 38,7; 46,0 e 50,1%, respectivamente.Item Life history of Amblyseius herbicolus (Chant) (Acari: Phytoseiidae) on coffee plants(Sociedade Entomológica do Brasil, 2007-06-26) Reis, Paulo R.; Teodoro, Adenir V.; Pedro Neto, Marçal; Silva, Ester A. daThe predaceous mite Amblyseius herbicolus (Chant) is the second most abundant phytoseiid on coffee plants (Coffea arabica L), after Euseius alatus DeLeon, in Lavras, MG, Brazil, associated to the vector of the coffee ring spot virus, Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae). Its life history was studied taking into account biological aspects, life table, predatory activity and functional and numerical responses in relation to the density of the prey. The adult female has longevity of 38 days when supplied with B. phoenicis. The intrinsic rate of population increase (r m) was 0.150 and the mean generation time (T) 25.3 days. The population doubles every 4.6 days. Thirty mites B. phoenicis /3-cm diameter coffee leaf arenas were separately offered to one specimen of each predator phase. Adult females were more efficient in killing all developmental phases of B. phoenicis, followed by the nymph stages. For the functional and numerical responses studies, from 0.14 to 42.3 immature specimens of the prey /cm² of arena were submitted to the predator, the preferred phase for predation. Predation and the oviposition of A. herbicolus increased with increasing prey density, with a positive and highly significant correlation. Regression analysis suggests a functional type II response, with a maximum daily predation near 35 B. phoenicis /cm² /one adult female.Item Susceptibilidade de seis cultivares de café arábica às moscas-das-frutas (Diptera: Tephritoidea) em sistema orgânico com e sem arborização em Valença, RJ(Sociedade Entomológica do Brasil, 2007-06-26) Aguiar-Menezes, Elen L.; Souza, Silvana A.S.; Santos, Carlos M.A.; Resende, André L.S.; Strikis, Pedro C.; Costa, Janaína R.; Ricci, Marta S.F.Foram determinados os índices de infestação por moscas-das-frutas em seis cultivares de Coffea arabica L. nos sistemas com e sem arborização, sob manejo orgânico. O delineamento experimental foi inteiramente casualizado com parcelas sub-subdivididas e quatro repetições. Uma amostra de 250 g de frutos maduros por parcela foi colhida em maio de 2005. As cultivares ‘Icatu Amarelo’ e ‘Catucaí Amarelo’ mostraram menor susceptibilidade aos tefritídeos, nos dois sistemas de cultivo. Quanto aos lonqueídeos, ‘Oeiras’, ‘Catucaí Amarelo’ e ‘Catuaí Vermelho’ foram as cultivares menos susceptíveis no sistema arborizado, não havendo diferença entre as cultivares no sistema sem arborização. Dos frutos foram obtidas as seguintes espécies de Tephritidae: Ceratitis capitata (Wiedemann), Anastrepha fraterculus (Wiedemann) e A. sororcula Zucchi (Tephritidae). Os lonqueídeos foram representados por: Neosilba bifida Strikis & Prado, N. certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. pseudopendula (Korytkowski & Ojeda), Dasiops rugifrons Hennig, Neosilba n.sp.10 e Neosilba n.sp.14.Item Infectividade natural por Xylella fastidiosa Wells et al. de cicadelíneos (Hemiptera: Cicadellidae) de lavouras cafeeiras do Paraná(Sociedade Entomológica do Brasil, 2007-06-26) Silva, Michele R.L.; Meneguim, Ana M.; Paião, Fernanda G.; Meneguim, Luciana; Canteri, Marcelo G.; Leite Jr, Rui P.Xylella fastidiosa Wells et al. é uma bactéria gram-negativa, limitada ao xilema de plantas e responsável por doenças de importância econômica em diversas culturas, como a requeima-da-folha ou atrofia-dos-ramos em cafeeiro. É transmitida por insetos sugadores de xilema e quatro espécies de cigarrinhas já foram descritas como transmissoras do patógeno para cafeeiro. O objetivo deste trabalho foi determinar o grau de infectividade natural por X. fastidiosa em cinco espécies de cigarrinhas Cicadellidae potencialmente transmissoras da bactéria para cafeeiro: Acrogonia citrina Marucci & Cavichioli, Bucephalogonia xanthophis (Berg), Dilobopterus costalimai Young, Oncometopia facialis (Signoret) e Sonesimia grossa (Signoret). As coletas foram realizadas em lavouras cafeeiras de cinco municípios das regiões Norte e Noroeste do Paraná, de outubro de 1998 a novembro de 2001. O total de 806 amostras contendo de três a cinco insetos foi examinado para presença de X. fastidiosa utilizando os testes de PCR e nested PCR. Os resultados obtidos revelaram a presença de X. fastidiosa em amostras de todas as cinco espécies de cigarrinhas nas duas regiões cafeeiras. O potencial infectivo natural das amostras foi de 30,4% e variou de 2,2% para O. facialis a 68,8% para A. citrina. As cigarrinhas coletadas na primavera apresentaram tendência para menor infectividade natural de X. fastidiosa quando comparadas com as amostras coletadas nas outras três estações do ano. Os resultados obtidos revelaram o grande potencial de disseminação de X. fastidiosa por insetos vetores em cafeeiros no Paraná.Item Seed storage proteins in coffee(Sociedade Brasileira de Fisiologia Vegetal, 2001) BAÚ, SANDRA M. T.; MAZZAFERA, PAULO; SANTORO, LUIZ G.It has been reported that Coffea arabica seeds contain as the main reserve protein, a legumin-like protein, constituted of two subunits, alpha and beta, of approximately 35 and 20 kDa. In this work the seed proteins of several coffee species and varieties were investigated by SDS-PAGE and gel filtration. No differences were observed in the electrophoretic profiles among varieties of C. arabica, however, marked differences were observed among species, or even among individuals of some species. In general, the molecular weight of the subunits alpha and beta accounted for a monomer of 48 to 62 kDa. However, native molecular weight obtained by gel filtration showed that for most of the species there is association of 6 of such proteins, in a hexamer. The most marked difference was observed for C. canephora and C. racemosa. The former clearly showing isoforms of the subunits, and the later showing absence of the beta subunit. The influence of proteases in this observations is discussed.Item Effects of fruiting on the growth of Arabica coffee trees as related to carbohydrate and nitrogen status and to nitrate reductase activity(Sociedade Brasileira de Fisiologia Vegetal, 2001) AMARAL, JOSÉ A.T.; MATTA, FÁBIO M. DA; RENA, ALEMAR B.Active vegetative and reproductive growth in field-grown trees of Coffea arabica L. in Viçosa (20º45’S, 650 m altitude), south-eastern Brazil, occur concurrently. The overall patterns of branch growth and leaf area gain were to a certain extent altered by fruit removal, with growth rates being remarkably greater in de-fruited trees. The content of N-NO3 was not affected by fruiting, whilst that of amino-N was greater in de-fruited than fruiting trees most of the time, but the differences were not large enough to have significantly contributed to the increased growth rates in de-fruited trees. Leaf nitrate reductase activity was greater in plants bearing fruit than in non-bearing ones most of the time; activity was roughly inversely associated with growth. Although the roots contained much more nitrate than the leaves, the root nitrate reductase activity was much lower and not affected by fruiting. Much of the restrictive effects of fruiting on vegetative growth appeared to be associated to starch exhaustion, in addition to the outstanding effect of supra-optimum temperatures per se.Item Biological activities of the fermentation extract of the endophytic fungus Alternaria alternata isolated from Coffea arabica L.(Universidade de São Paulo, Faculdade de Ciências Farmacêuticas, 2009-12) Fernandes, Maurette dos Reis Vieira; Silva, Tales Alexandre Costa e; Pfenning, Ludwig Heinrich; Costa-Neto, Cláudio Miguel da; Heinrich, Tassiela Andréa; Alencar, Severino Matias de; Lima, Marisa Aparecida de; Ikegaki, MasaharuA total of 22 endophytic fungi isolated from coffee (Coffea arabica L.) were cultivated in vitro and their crude extracts tested. The screening was carried out using the agar diffusion method against Staphylococcus aureus, Escherichia coli and Candida albicans. The most effective isolate was Alternaria alternata, and subsequently, its extract was assayed. The total phenolic content was 3.44 μg GAE/mg of the crude extract. For the antibacterial and antifungal activity assays, minimum inhibitory concentrations (MIC) and minimum bactericidal and fungicidal concentrations (MBC and MFC) were determined. The ranges of MIC values were 50-100 μg/mL for S. aureus and 400-800 μg/mL for E. coli. The extract did not show activity in the tested concentrations for C. albicans. The fungal crude extract was assayed for antioxidant activities. Its ability to scavenge DPPH radicals and antioxidant activity by β-carotene/linoleic acid system oxidation was not significant. In addition, antitumor activity was studied using the MTT assay. At a dilution of 400 μg/mL, the extract displayed a cytotoxic activity of approximately 50% towards HeLa cells in vitro. The results indicate that endophytic fungi could be a promising source of bioactive compounds and warrant further study.Item Zoneamento agroclimático da cultura do café para a Bacia do Rio Doce(Sociedade Brasileira de Meteorologia, 2008-01-28) Nunes, Edson Luís; Amorim, Ranieri Carlos Ferreira de; Souza, Wesley Gonçalves de; Ribeiro, Aristides; Senna, Mônica Carneiro Alves; Leal, Brauliro GomesObjetivou-se neste trabalho, através da geoespacialização, a identificação das regiões aptas, restritas e inaptas ao cultivo do café (Coffea arabica L.) na Bacia do Rio Doce. Utilizou-se para tal, dados de temperatura e déficit hídrico de 50 estações meteorológicas instaladas na bacia e em bacias limítrofes. Os dados de déficit hídrico foram determinados utilizando o balanço hídrico segundo Thornthwaite & Mather (1955). Foram identificadas regiões equivalentes a um terço da bacia, localizadas na parte central e no nordeste da mesma, como sendo inaptas ao cultivo do café, conforme os critérios de produtividade relacionados com as exigências térmicas e hídricas da cultura.