Bragantia
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Item Physical and chemical attributes of beans damaged by the coffee berry borer at different levels of infestation(Instituto Agronômico (IAC), 2024-05-09) Silva, Sabrina Alves; Pereira, Rosemary Gualberto Fonseca Alvarenga; Chalfoun, Sara Maria; Teixeira, Alexandre ResendeThe physical and chemical attributes of coffee beans have a direct relation with the sensory quality of the beverage and the commodity’s market value. The coffee berry borer is a pest that causes a worldwide harm, and its infestation compromises bean health and composition. The objective of this study was to analyze the effect of infestation levels on beans physical and chemical parameters. Coffee samples were collected, and the damaged beans present in the samples were classified as to infestation level. The centesimal composition, color, quantification of bioactive compounds, and organic acids were evaluated. The L* and b* parameters of the CIELab color system were found to be significantly different between infestation levels. For chemical parameters, beans with major levels of infestation were found to differ from the others in the content of sugars, lipids, soluble solids, total titratable acidity, electrical conductivity, potassium leaching, succinic acid, and acetic acid. The presence of pests did not affect the bioactive compounds present in the coffee beans.Item Factors influencing the performance of phosphites on the control of coffee leaf rust(Instituto Agronômico (IAC), 2021) Honorato Júnior, Jaime; Debona, Daniel; Zambolim, Laércio; Rodrigues, Fabrício ÁvilaThis study investigated the effect of different phosphites on the control of coffee leaf rust (CLR) caused by Hemileia vastatrix, considered the major disease affecting coffee yield worldwide. Three-month-old coffee plants were sprayed with two doses each of the phosphite solutions (standard and double), as follows: K (40% P2O5; 1.5 and 3 mL·L-1), K (30% P2O5; 3 and 6 mL·L-1), Cu (2.5 and 5 mL·L- 1), Mn+Zn (3 and 6 mL·L-1) and Na (3 and 6 mL·L-1) 24 h before being inoculated with H. vastatrix. Leaves were not washed or washed with deionized water after the foliar phosphites spray. Plants sprayed with water served as the control treatment. Inoculation was performed on the abaxial side of the first pair of expanded leaves using a camel hairbrush with a suspension of urediniospores (1 mg per leaf). All phosphites applied at the standard doses (from 1.5 to 3 mL·L-1) reduced the total number of pustules (TNP) per leaf by 28-69% regardless of washing treatment. The biggest reductions were observed for Cu phosphite, which decreased the TNP per leaf by 60 and 69% without and with leaf washing, respectively. A similar trend was observed when the double doses of phosphites (from 3 to 6 mL·L-1) were used, though Na phosphite without leaf washing and Mn/Zn phosphite without and with leaf washing were not efficient to reduce the TNP per leaf. Without leaf washing, only Cu and Na phosphites decreased CLR severity at the standard doses (53-61%), whereas all phosphites, except the Mn/ Zn phosphite, reduced CLR severity at the double dose. The CLR severity was decreased using K 30%, K 40% and Cu phosphites When applied at the standard doses with leaf washing (41-59%). With double doses, only Cu and Na phosphites decreased CLR severity by 55% for both treatments. In conclusion, the efficiency of the phosphites for CLR control varied according to the accompanying cation, dose and washing conditions. The Cu phosphite resulted in the best CLR control regardless of the dose used and the washing conditions.Item Estudos sobre a mancha aureolada do cafeeiro(Instituto Agronômico (IAC), 1960-04) Costa, A. S.; Silva, Darcy Martins daThe widespread halo blight onslaught on young coffee plantings in 1955 and 1956 was not repeated in the following two years except in one or two instances. Plantings that had been severely affected in those years recovered naturally. The writers had difficulty in finding a few diseased leaves in many of them. Spraying tests with two antibiotics and 15 fungicides applied approximately every five days for four consecutive months did not offer any promise of control in a severely affected planting, although a slight favorable response was observed as a result of the application of two copper compounds. Treatments aimed at modifying the nutritional status of the plants did not induce any response in the way of increasing the coffee plant resistance against halo blight. A non-identified bacteria obtained from a bean planting that showed bean halo blight-like symptons was capable of inducing halo blight on coffee. Comparative inoculation tests showed, however, that the two disease-inducing agents were not identical. The bean bacteria induced halo blight symptoms on coffee leaves indistinguishable from those caused by the coffee bacteria, but the former organism was less pathogenic to coffee and more to bean than the latter.Item Avaliação do nível de resistência do cafeeiro a H. Vastatrix(Instituto Agronômico (IAC), 1978) Costa, W. M.; Eskes, A. B.; Ribeiro, I. J. ATo study horizontal resistance of coffee plants to H. vastatrix quantitative measurements on resistance are necessary. In this paper the results' of some greenhouse and laboratory tests are compared to field observations. Regular field readings -within the Icatu population, using a 6 point scale for disease access, have shown that a continuous variation for resistance exists within this population. Grafts of 55 plants of Icatu have been inoculated in the greenhouse with race I I of the pathogen. Besides readings using the 6 point scale, estimates on sporulation rate and lesion size were made. The results show a good relation between field and greenhouse observations. Lesion size, however, was less correlated with disease incidence since many plants show large chlorotic areas with only sparse sporulation. As a laboratory method detached leaves and leaf disks have been inoculated and maintained at high relative humidity. Conservation of detached leaves was insatisfactory and this method has been subsequentely abandoned. Leaf disks, when placed, on wetted filter paper in petri dishes, stayed green and apparently healthy for even more than 120 days. An inoculation experiment, using a susceptible, moderate susceptible and resistant plant of Icatu, indicates that the rate of infection of the leaf disks could be a promising parameter for quantitative disease assessments. Investigation with other plant material will be undertaken to further determine the effectiveness of this method.Item Efeito de alta temperatura no desenvolvimento de Hemileia vastatrix em cafeeiro suscetível(Instituto Agronômico (IAC), 1978) Ribeiro, Ivan José Antunes; Monaco, Lourival Carmo; Tisseli Filho, Otávio; Sugimori, Mauro HideoFoi estudado o efeito de temperaturas elevadas no desenvolvimento da ferrugem do cafeeiro, verificando-se que a exposição de plantas a temperatura próxima de 40°C por quatro horas durante quatro dias foi suficiente para impedir a evolução da moléstia. Períodos menores foram ineficientes para afetar o desenvolvimento do fungoItem Relação entre grau de resistência a Hemilea vastatrix e produtividade no café Icatu(Instituto Agronômico (IAC), 1978) Costa, W. M.Plantas de cinco populações do café icatu foram classificadas em seis tipos de reação, de acordo com o grau de inf ecção pela H. vastatríx, sendo grau 1 correspondente a plantas resistentes e grau 6 a suscetíveis. Procurou-se determinar a relação entre a produtividade e os tipos de reação apresentados, bem como a variabilidade de produção em cada um desses tipos de reação. Verificou-se que não diferiram estatisticamente as médias de produção de plantas selecionadas correspondentes a cada tipo de reação ao ataque da ferrugem, dentro de quatro populações de icatu estudadas (H 4782-7, H 4782-10, H 4782-13 e H 3851-2), bem como entre essas populações. As plantas em cada população foram também agrupadas, de acordo com sua pro- dução, em intervalos de 2kg, determinando-se a porcentagem de plantas dos vários tipos de reação ao patógeno nesses intervalos. Verificou-se que nos intervalos mais altos, a partir de 20kg, são mais freqüentes as plantas com reação dos tipos 1, 2 e 3, indicando que aquelas mais suscetíveis, dos tipos 5 e 6, possivelmente tiveram sua produtividade afetada pelo maior ataque da ferrugem. A variabilidade na produção total apresentada pelas plantas individuais das dife- rentes progenies do café icatu foi acentuada, dando margem à seleção de cafeeiros pro- dutivos dentro dos diferentes tipos de reação ao ataque de H. vastatríx.Item Evidência electrono-microscópica de multiplicação dos vírus do mosaico do fumo e de vira-cabeça, em tecido foliar de cafeeiro(Instituto Agronômico (IAC), 1970-08) Kitajima, E. W.; Costa, A. S.Coffea plants (Coffea arabica L.) may be infected with vira-cabeça (Brazilian tomato spotted wilt) or tobacco mosaic (TMV) viruses, by mechanical means. Vira-cabeça virus (VCV) induces on leaves of ino- culated plants, chlorotic spots, resembling ringspot, while a virulent isolate of TMV causes chlorotic lesions with a necrotic center. In both cases, the viruses did not become systemic. Thin section profiles of leaf tissues obtained from the lesions caused by TMV or VCV were examined in the electron microscope. In cells from chlorotic lesions of TMV-inoculated coffea leaves, many cytoplasmic inclusions, with a fibrous aspect, were found. These inclusions were observed in epidermal, spongy and palisade parenchyma, but not in the vascular region. The rod-like particles, components of the inclusion are considered as TMV in situ. The fibrous inclusions were still identifiable, even in completely necrotic cells. X-body-like inclusions on the other hand, could not be seen. In cells from the lesion induced by VCV, spheroidal particles, iden- tified as those of the inoculated virus, were found mostly in epidermal cell. The particles were always within the endoplasmic reticulum elements. The finding of a large number of virus particles, in foliar tissue of coffea, infected by TMV or VCV, is considered as an evidence for the multiplication of these virus in the inoculated tissue, and supports previous pathological observations.Item Efeitos climáticos na ocorrência de Orthezia insignis Browne, 1887 (Homoptera - Ortheziidae) em cafezais do Paraná(Instituto Agronômico (IAC), 1975-01) Nakano, Octavio; Parra, José Roberto Postali; Pereira, Antônio RobertoOs insetos (cochonilhas) pertencentes à família Ortheziidae constituem sérias pragas nas regiões que apresentam períodos quentes e secos, tanto assim que a espécie Orthezia praelonga Douglas acarreta graves prejuízos à citricultura da Baixada Fluminense, onde as condições climáticas lhe são favoráveis. Por outro lado, a espécie O.insignis, embora cosmopolita e grandemente disseminada pelos estados do Brasil, nunca foi relatada atacando cafezais do Paraná. A presente nota é uma tentativa de explicação, com base nos parâmetros climáticos, da ocorrência de um surto de O.insignis, em fevereiro de 1968, nos cafezais das regiões de Marialva, Maringá e Rolândia, no Estado do Paraná. O desaparecimento da praga um mês após, sem que medidas fitossanitárias fossem tomadas, foi o que motivou uma abordagem climática do evento.Item Café Icatu como fonte de resistência a Colletotrichum coffeanum(Instituto Agronômico (IAC), 1976-10) Carvalho, A.; Monaco, L. C.; Vossen, H. A. M. Van derLinhagens e progênies do cultivar icatu, selecionadas em Campinas, foram testadas na Coffee Research Station, Ruiru, Quênia, a fim de avaliar o grau de resistência ao ataque de Colletotrichum coffeanum, agente responsável pela moléstia mais conhecida por CBD. Os dados de infecção obtidos para 11 linhagens e sete progênies foram comparados com os dos cultivares testemunhas Rume Sudan, resistente, e SL 28, suscetível. Considerando apenas a freqüência de resistentes, com grau 1 de infecção, destacaram-se a progênie H 4782-10 M e a linhagem LCH 3851-4 T. As populações com graus de 1 a 4 de resistência ocorreram em menor escala do que no Rume Sudan, porém salientou-se a progênie H 4782-10 M, com elevada resistência. As maiores porcentagens de plantas suscetíveis foram verificadas nas linhagens LCH 3849-7 M e LCH 4782-13 T, as quais se aproximam da linhagem suscetível SL 28. Os dados preliminares indicam que o germoplasma icatu, como o híbrido de timor, oferece perspectivas de constituir razoável fonte de resistência genética ao agente da CBD.Item Influência do tempo de pulverização com aparelho pneumático costal, na cobertura foliar do cafeeiro(Instituto Agronômico (IAC), 1976-08) Lorena Neto, Bernardo; Corrêa, Hermes GeraldoEstudou-se a influência do tempo que plantas de café permanecem sob um fluxo pulverizado, na cobertura foliar obtida. Foi aplicado um volume de 300 ml por planta durante os tempos de 20, 30 e 40 segundos. A cobertura foliar foi avaliada com a técnica do traçante fluo- rescente. Analisados estatisticamente os resultados, concluiu-se que o tempo de 30 segundos foi suficiente para a pulverização das quatro plantas de uma cova nas condições do ensaio, sendo de 0,60 litro/minuto a vazão do bico do pulverizador.