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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 Atividade antifúngica, in vitro, do óleo de café verde(Instituto Biológico, 2016) Elizei, Virgínia Guerra; Chalfoun, Sara Maria; Botelho, Deila Magna dos Santos; Rebelles, Pedro Paulo ReisO objetivo deste trabalho foi avaliar o efeito do contato direto e da fração volátil do óleo de café verde, testado nas concen trações de 500, 1.000, 1.500 e 2.000 μL L-1, sobre o crescimento micelial e a esporulação dos fungos Penicillium roqueforti e Rhizopus stolonifer. O óleo essencial de cravo-da-índia na concentração de 800 μL L-1 foi utilizado para comparação. Nas concentrações de 1.500 e 2.000 μL L-1, o óleo de café verde em contato direto pro porcionou redução da esporulação do fungo R. stolonifer, sendo estatisticamente semelhante ao óleo de cravo-da-índia. Na fração volátil do óleo de café verde, observou-se redução significativa da esporulação de P. roqueforti e R. stolonifer na concentração de 2.000 μL L-1. O óleo de café verde, em contato direto ou por volatilização, reduziu significativamente o crescimento micelial e a esporulação de ambos os fungos em comparação com a testemunha.Item Selection of fungal isolates with potential for phosphate solubilation and formulation of inoculant for coffee crops(Editora UFLA, 2019-07) Chalfoun, Sara Maria; Angélico, Caroline Lima; Resende, Mário Lúcio Vilela de; Moraes, Graziella Evaristo deThe dependence on chemical fertilizers for the future of agriculture will result in additional soil health losses, possibility of water contamination and continued currency avoidance due to the increasing dependence on imports. The indiscriminate use of synthetic fertilizers has polluted the soil and watersheds, destroying useful microorganisms and insects, what makes crops more susceptible to diseases. Considering this critical scenario, microorganisms have stood out as a potential alternative for maintaining the productivity, reliability and sustainability of the global food chain. In order to increase the productivity and/or reduce the amount of fertilizers, as well as to meet the requirements for the use of low-solubility phosphorus sources, microorganisms were isolated from the rhizosphere and artificially cultivated. Subsequently, they were selected regarding their potential for solubilizing phosphorus and incorporated into a low-cost matrix. A microbial inoculant was thus developed and tested in a coffee crop. It was possible to formulate an inoculant based on an isolate selected from Aspergillus niger, using an inactivated seed and sodium alginate as matrices. It was also observed that there was a greater correlation between the evaluated parameters and increasing doses of the inoculants when Araxá apatite was used as source of phosphorus, proving the importance of the inoculants as release factors and availability of phosphorus in the case of sources less soluble, giving Brazilian agriculture greater autonomy in the input market.Item Conductivity to rust in coffee under different wooden and fruit tree intercropping systems(Editora UFLA, 2018-04) Chalfoun, Sara Maria; Martins, Carla de Pádua; Matos, Christiano Sousa Machado; Pereira, Alessandro Botelho; Silva, Vicentina NazaréThe coffee intercropping with fruit and wooden species of economic value has been presented as a viable alternative for coffee cultivation in order to mitigate adverse environmental conditions for coffee trees, among other factors. Adapting the crop management to the new conditions stablished by the system is fundamental to obtain success on intercropping. One of the most serious diseases for the crop is the rust caused by Hemileia vastatrix., which may have its severity increased in function of the microclimate conditions provided by the trees. In this sense, the disease behavior under different intercropping systems and consequent different need to adapt the control measures when compared to the cultivation in full sun should be investigated. The present study was conducted aimed to verify the impact of tree systems composed by three wooden species, Cedar (Acrocarpos fraxinifolius), African mahogany (Khaya ivorensis ), Teak (Tectona grandis ) and two species of fruit trees, avocado (Persea Americana) and macadamia (Macadamia integrifolia) planted in different spacing over the occurrence and evolution of rust.It was possible to observe that coffee rust began to progress in the coffee plants from the month of February reaching a peak in September in all the treatments. Differences were observed in the progress curves of the disease, especially in the species that presented larger canopy such as avocado. Further studies are suggested with the purpose of establishing the microclimatic changes provided by the cultivation of different wooden and fruit species in intercropping with coffee, according to the dynamics of the climate and their development.Item Biological control and bioactive microbial metabolites: a coffee quality perspective(Editora UFLA, 2010-09) Chalfoun, Sara MariaThe improvement of techniques of biological control and the use of metabolites produced by microorganisms to obtain products that can be applied in various fields, is getting stronger in face of the undeniable advantages in relation to the models currently in adopted. This review, besides general considerations about the principles and the application of measures of biological control and usage of metabolites produced by microorganisms as sustainable alternatives for the agrochemical segment, among others, reports the experience lived by the author and the institutions to which she is associated, concerning identification, characterization and development of a biological fungicide resulting from the encapsulation of the fungus Cladosporium cladosporioides (Fres.) de Vries, after proving its bioprotecting action on the quality of the coffee. The possibility of using microorganisms as a source of metabolites obtained from biological extracts, with applications in various fields, is also presented and discussed.