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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Dynamic Behavior of Coffee Branches: an Analysis Using the Finite Element Method(Instituto de Tecnologia do Paraná - Tecpar, 2024-01-12) Melo Junior, Wellington Washington Andrade de; Santos, Fábio Lúcio; Scinocca, Francisco; Rosa, Pablo Antunes da; Magalhães, Ricardo RodriguesThe use of computational simulation techniques is an important tool for the coffee harvesting issues, particularly the finite element method. The method is widely used in the structural analysis of agricultural machinery, as well as in the analysis of the stresses and vibrations of coffee branches and peduncles during the harvesting process. The present study aimed to develop three-dimensional finite element models of the plagiotropic branches of the Catuaí Vermelho variety of Arabica coffee in different positions along the orthotropic branches of the plant; considering high-fidelity models. Additionally, by considering the branches’ experimental properties (physical-mechanical), the natural frequencies and vibration modes of the branches were determined by means of computer simulations. First, the geometric properties of the coffee branches were obtained by means of two images taken using a professional camera to obtain the input data of the virtual simulation. For the mechanical properties, it was used a semi-analytical digital scale, to obtain the mass of the specimens. The modulus of elasticity was determined using a universal testing machine. The variability in the simulated natural frequencies could be identified, which was on the order of 30% for the first frequency, regardless of the position of the branch in the plant. These values were lower for the other frequencies. Linear regression fits showed a coefficient of determination, and correlation tests were used to verify the relationship between the values obtained numerically and experimentally, which were validated by using experimental data using the modal analysis techniques.Item Growth promoting fungi increase the quality of Coffea canephora seedlings Pierre ex a. Froehner(Universidade Federal de Lavras, 2023-04-28) Alves, Jucélia Rodrigues; Celestino, Flávio Neves; Moraes, Alisson Gomes de; Reis, Ricardo Arizono dos; Grecco, Eduardo DomingosGrowth promoting fungi have shown an important role in the development of agricultural crops. Among these fungi, the genus Trichoderma stands out, and the entomopathogenic fungi of the genus Beauveria and Metarhizium have been gaining greater importance. Thus, the aim of the present study was to evaluate the vegetative growth of conilon coffee seedlings inoculated with growth promoting fungi. For the production of seedlings, cuttings of clone A1 of conilon coffee were used, in standard substrate. The growth promoting fungi Trichoderma harzianum, Beauveria bassiana and Metarhizium anisopliae were used at a concentration of 1 x 107 conidia.mL-1, inoculated via soil and leaf. Vegetative growth evaluations were performed at 180 days after cutting. The treatments corresponded to a 4 x 2 factorial arrangement, in a randomized block design, with three replications, totaling 24 plots. The data were submitted to analysis of variance and the means compared by the Scott-Knott grouping method (p ≤ 0.05). The treatments did not promote gains in plant height, stem diameter, root length, root fresh mass, leaf area, shoot/root fresh and dry mass of conilon coffee seedlings. Growth promoting fungi T. harzianum and B. bassiana promoted a greater number of leaf pairs, greater fresh mass of aerial part and greater dry mass of aerial part. Additionally, T. harzianum promoted greater root dry mass in conilon coffee seedlings. Only for the parameter number of leaf pairs, the inoculation via soil was greater than via leaf, while for the other parameters there was no difference regarding the inoculation method.Item Digital imaging of coffee leaves under different nitrogen concentrations applied to soil(Universidade Federal de Viçosa, 2022-01-09) Godoy, Leandro José Grava de; Carvalho, Alex Mendonça de; Freitas, Ana Flávia de; Botelho, Cesar Elias; Garibaldi, João Luís Teodoro; Ferrari, SamuelBrazil is the largest Coffea arabica L. producer and exporter in the world market. In view of the need for nitrogen fertilization, the objective of this work was to evaluate the use of digital images of coffee leaves as a function of nitrogen concentration and cultivars, as well as to evaluate the most adequate sampling of this technique to predict leaf nitrogen. The experiment was set in a greenhouse, at UNESP - Experimental Campus of Registro-SP, using 12L pots with medium sand. A completely randomized design was adopted, in a 4 x 2 factorial scheme, with four concentrations of N (0, 50, 100 and 200 mg dm-3), and two coffee cultivars (Mundo Novo and Obatã), with ten replications. The variables evaluated were: hue, dark green color index (DGCI), leaf area and leaf nitrogen content. The hue and DGCI were influenced by N concentration, cultivar and are dependent on the day after treatment application and the number of leaves used. The use of five leaves per replication was more adequate to estimate leaf N content. Hue, DGCI and leaf area were higher in Obatã depending on the day after application of the treatment and N concentration.Item New model of clonal garden for the production of robusta coffee plantlets(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2022-09-12) Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Diocleciano, João Maria; Rocha, Rodrigo Barros; Dias, Jairo Rafael Machado; Verdin Filho, Abraão CarlosThe objective of this work was to evaluate the production of cuttings of Coffea canephora genotypes, in a new system for training mother plants called “vertical clonal garden”. The proposed new system consists of training coffee plants with only one shoot and without bending the main shoot, so that the secondary orthotropic shoots, from which the clonal cuttings will be taken, are formed across the length of the stem in the vertical direction. The capacity for the production of cuttings of ten hybrid genotypes of coffee plants was evaluated over ten production cycles. The 'BRS 2314', 'BRS 3213', and 'BRS 3210' genotypes showed cutting production per cut of 425,000 cuttings per hectare, considered above the obtained average. The 'BRS 3193', 'BRS 2336', 'BRS 3220', and 'BRS 3137' genotypes were the least productive. Coffee plants trained in the “vertical clonal garden” system can produce about 425,000 cuttings per hectare per harvest period or about 1.275 million cuttings per hectare per year, over three harvest periods, with a greater ease in crop management and treatments.Item Exploring the diversity of microorganisms and potential pectinase activity isolated from wet fermentation of coffee in northeastern Peru(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2023-01-09) Fernandez-Güimac, Samia Littly Jahavely; Perez, Jhordy; Mendoza, Jani Elisabet; Bustamante, Danilo Edson; Calderon, Martha SteffanyIn this study, the microbiota associated with coffee fermentation from two regions from northern Peru was evaluated. Bacteria and fungi were isolated from coffee farms in the Amazonas and Cajamarca regions and identified using molecular markers 16S rRNA and ITS. The potential pectinase activity was registered by the formation of a transparent halo around colonies. As a result, 29 and 09 species belonging to bacteria and fungi, respectively, were found. The bacterial genera Lysinibacillus and Stenotrophomonas and the fungal genus Aspergillus accounted for the highest number of species isolated from coffee ferments. Forty-one out of 71 isolates showed some type of pectinase enzyme activity, and they included 23 isolates from Cajamarca and 18 from Amazonas. Nevertheless, only three bacterial species registered the formation of transparent halos and showed relevant potential pectinase enzyme activity, namely, Lysinibacillus xylanilyticus, Stenotrophomonas maltophilia, and Stenotrophomonas pavanii, which were all from the Cajamarca region. These species could be further investigated by quantifying enzymes activity and performing other biochemical properties to prototype starter cultures. Accordingly, the study of indigenous microorganisms with biological potential will be essential to increase the coffee value chain and improve the incomes of farmers.Item Food habits of the Cougar Puma concolor (Carnivora: Felidae) in the Central Andes of the Colombian Coffee Region(Museu de Zoologia da Universidade de São Paulo, 2020) Castillo, Diana Camila Muñoz; Arbeláez, Pauline Perry; Arias-Monsalve, Héctor Fabio; Ramírez-Chaves, Héctor E.The feeding habits of the cougar have been scarcely studied in Colombia, despite its importance in the ecosystems it inhabits. In this study, we analysed the diet of the cougar using 53 feces samples collected from several sites in the Central Andes of Colombia’s Coffee Growing Region. To identify prey species, we examined and compared bone fragments and hairs found in each sample with descriptions published in relevant literature and with specimens from the Natural History Museum of the Universidad de Caldas, Colombia. We found that rabbits (Sylvilagus sp.) provided half of the relative biomass consumed by the cougar (50%). Other preys identified belong to representatives of medium and large mammals such as marsupials (Didelphis: 10%), sloths (Choloepus: 9%), rodents (Coendou: 10%, Cuniculus: 9%), and deer (Mazama: 9%). Of the preys, Coendou rufescens has not, to our knowledge, been previously included in cougar diet literature. The curve of accumulation of species indicated that the number of samples obtained in this work fully describe the diet of this feline. Neither domestic species were recorded in this work, nor were there any relationships between the dry or rainy seasons and the consumption of prey species. The comparison of the information reported in this study and others carried out in the Andes may indicate the general nature of this feline’s diet and its adaptability to the prey species found in each area, since these vary in each one of them. It is probable that the obtained trophic niche value (0.33) is due to the abundance of rabbits present in the study area. It is also probable that the cougar has not consumed domestic species since, although it is close to cattle ranches, it has enough of wild prey in the area to supply its needs. The results of this study may help to improve our understanding of the feeding habits of this predator and its interaction with other species in this important region of Colombia. This will, in turn, promote major comprehension of the role of cougars in the Colombian Cordilleras and lead actions for their conservation.