Biblioteca do Café
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Resultados da Pesquisa
Item Amostragem de cigarrinhas (Hemiptera, Cicadellidae) através de armadilhas de Moericke em cafeeiro arábica(Instituto Biológico, 2007) Lara, R. I. R.; Perioto, N. W.; Freitas, S. deEste estudo teve por objetivo avaliar o padrão de variação populacional de cigarrinhas (Hemiptera, Cicadellidae) associadas ao cafeeiro, em Cravinhos, SP. As amostragens foram realizadas, semanalmente, no período de abril de 2005 a abril de 2006 através de 60 armadilhas de Moericke instaladas nos terços médio e inferior das plantas. Foram coletados 3.243 exemplares de cigarrinhas pertencentes a 8 espécies: Bahita infuscata, Coelidiana diminuta, Dilobopterus costalimai, Docalidia bifurcata, Joruma (Joruma) sp., Labocurtidia sp., Oncometopia facialis e Scaphytopius irrorellus. As maiores abundâncias destes cicadelídeos associados à cultura do cafeeiro ocorreram no período chuvoso; as espécies de cicadelídeos coletadas foram constantes e as armadilhas de Moericke instaladas no terço médio das plantas foram mais eficientes para a captura deste grupo de insetos. Verificou-se correlação positiva significativa entre os valores populacionais de D. costalimai com a pluviosidade e as temperaturas máxima e mínima e, para O. facialis, foi apenas com a temperatura mínima.Item Selection for durable resistance to leaf rust using test-crosses on IAPAR-59 and Tupi IAC 1669-33 cultivars of Coffea arabica(Instituto de Tecnologia do Paraná - Tecpar, 2007-10-05) Sera, Gustavo Hiroshi; Sera, Tumoru; Ito, Dhalton Shiguer; Azevedo, José Alves de; Mata, João Siqueira da; Doi, Deisy Saori; Ribeiro Filho, ClaudionorThe aim of this study was to identify plants of the IAPAR-59 and Tupi IAC 1669-33 coffee cultivars with less defeated resistance genes by the rust races present at IAPAR (Londrina, Paraná State, Brazil) using test-crosses. Eighteen test-crosses derived from hybridizations between 'IAPAR-59' or 'Tupi IAC 1669-33' with susceptible coffee to the rust disease were evaluated. Six hybrids were used as susceptible standards originated from hybridizations between two susceptible coffee plants. Many parental plants of the 'IAPAR-59' and 'Tupi IAC 1669-33' presented more defeated resistance genes against rust races present at IAPAR than others of these cultivars or the genes were in heterozygous, because of segregant susceptible plants observed in some test-crosses. The test-crosses were very efficient to identify plants with less defeated resistance genes to the H. vastatrix. Coffee plants considered resistants would must be made test-crosses to verify which plants presented less and/or more defeated genes in homozygous.Item 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.Item 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.Item Efeito de diferentes temperaturas e exigências térmicas da cochonilha-branca Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) em cafeeiro(Instituto Biológico, 2008) Correa, L. R. B.; Santa-Cecília, L. V. C.; Souza, B.; Cividanes, F. J.Dentre as várias espécies que compõem a família Pseudococcidae, conhecida como cochonilhabranca, tem sido relatada como importante praga de diversas culturas. Considerando a grande variabilidade ambiental a que esse inseto está submetido, objetivou-se estudar aspectos biológicos dessa cochonilha em cafeeiro (Coffea arabica) em diferentes temperaturas e determinar as suas exigências térmicas. O experimento foi conduzido em câmaras climatizadas a 70 ± 10% UR, 12 horas de fotofase e temperaturas de 15, 20, 25, 30 e 35ºC. Os resultados obtidos evidenciaram que a temperatura influenciou o desenvolvimento ninfal de P. citri,exceto o segundo ínstar de machos. A duração da fase ninfal de fêmeas variou de 77 a 30 dias quando se elevou a temperatura de 15 para 30º C e a longevidade das fêmeas foi maior para as condições extremas (15 e 30º C). Na fase ninfal, houve 100% de mortalidade quando expostas a 35º C, verificando-se menor valor (30%) a 25º C. A velocidade de desenvolvimento em função da temperatura ajustou-se ao modelo linear da hipérbole. Analisando os dados de exigências térmicas verificou-se que o limite inferior de temperatura (Tb) foi menor para os diferentes ínstares dos machos em relação aos das fêmeas. Os resultados indicaram que as baixas temperaturas prolongaram o desenvolvimento do inseto, e que a temperatura mais favorável foi de 25º C e as mais desfavoráveis foram as de 15 e 35º C.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.