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Item Selection of genotypes of Coffea arabica for drought tolerance based on anatomical and physiological characteristics(Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, 2025-03-31) Santos, Cyntia Stephânia dos; Freitas, Ana Flávia de; Silva, Glauber Henrique Barbosa da; Tavares, Maria Clara dos Santos; Carvalho, Milene Alves de Figueiredo; Santos, Meline de Oliveira; Carvalho, Gladyston Rodrigues; Silva, Vânia AparecidaClimate change affects crop productivity, with forecasts for the coming years pointing to increased temperatures and changes in rainfall distribution. This paper aimed to identify genotypes of Coffea arabica that are potentially drought-tolerant. Seven germplasm genotypes of Timor Hybrid were evaluated in comparison to two cultivars considered as sensitive and drought-tolerant. These were submitted to two water treatments, the first maintaining water availability and the second with complete suspension of irrigation. The physiological characteristics analyzed were gas exchange and predawn leaf water potential. For leaf anatomy, characteristics of the leaf lamina, conductive vessels and stomata were evaluated. It was found that some genotypes were able to maintain gas exchange even under low water availability. For these genotypes, the analysis of leaf anatomy presented an increase in cuticle thickness on the adaxial face, in the relationship between polar and equatorial diameters of stomata, in addition to a lower vulnerability index. A positive relationship was observed between adaxial phase cuticle thickness and water use efficiency. The Timor Hybrid UFV 377-21, UFV 376-31 and the cultivar IPR100 were the highlights among the genotypes analyzed, which presented adaptations that allowed the maintenance of the hydric status in the initial development phase.Item Assessment of leaf anatomic and physiological characteristics and genetic divergence among Coffea arabica L. cultivars in the Brazilian Savanna(Escola de Agronomia - UFG, 2022-01-16) Santos, Cyntia Stephânia dos; Pereira, Fernanda Aparecida Castro; Mauri, Janaína; Viana, Mariana Thereza Rodrigues; Rodrigues, Gustavo Costa; Veiga, Adriano Delly; Bartholo, Gabriel Ferreira; Carvalho, Milene Alves de FigueiredoThe knowledge on cultivars is essential for parental choosing on breeding programs. This research aimed to study the genetic divergence of Coffea arabica L. cultivars from a germoplasm bank of the Embrapa Cerrados, Brazil, for leaf anatomic and physiological characteristics. A total of 23 cultivars were evaluated: Acaiá Cerrado MG1474, Araponga MG1, Catiguá MG1, Catiguá MG2, Catiguá MG3, Catiguá MG3 P4, Catiguá MG3 P5, Catiguá MG3 P7, Catiguá MG3 P9, Catiguá MG3 P23, Catiguá MG3 P51, Catuaí Amarelo IAC 62, Catuaí Vermelho IAC 15, Catuaí Vermelho IAC 81, Catuaí Vermelho IAC 99, Caturra Vermelho MG0187, Guatenano Colis MG0207, Mundo Novo IAC 379-19, Paraíso MG1, Pau Brasil MG1, Sacramento MG1, San Ramon MG0198 and Topázio MG1190. In addition to the genetic divergence, the broad sense heritability and coefficient of genetic and environmental variation were also evaluated. All characteristics showed high coefficients of genetic variation and heritability values greater than 70 %, indicating a predominance of genetic over environmental factors, and that these are characteristics likely to obtain genetic gain. Catiguá MG1, Catiguá MG3 P51 and Topázio MG1190 stood out, with superior gas exchange characteristics. Attributes related to gas exchange were important for cultivar differentiation, demonstrating that they can be used in the early selection of Coffea arabica L. genotypes.Item Variáveis Morfofisiológicas e Produtividade na Pré-seleção de Cafeeiros Cultivados no Cerrado do Planalto Central(Embrapa Café, 2022-08) Carvalho, Milene Alves de Figueiredo; Silva, Elisângela Aparecida da; Rodrigues, Gustavo Costa; Veiga, Adriano Delly; Guerra, Antonio FernandoO cultivo do cafeeiro em áreas de Cerrado utiliza o manejo de irrigação com suspensão hídrica no período reprodutivo visando à uniformização da florada, obtendo-se frutos em estádios de maturação mais uniformes e cafés com qualidade. Verificou-se o potencial de algumas variáveis morfofisiológicas em se correlacionar com a produtividade para serem utilizadas na pré-seleção de genótipos de Coffea canephora que melhor se adaptem ao manejo de irrigação utilizado no Cerrado. O experimento foi conduzido na região do Cerrado do Planalto Central avaliando-se sete clones de C. canephora no ano de 2016. As plantas passaram por um período de suspensão da irrigação de 56 dias para a uniformização da florada; as avaliações morfofisiológicas foram realizadas antes e no final do período de suspensão da irrigação e 2 dias e 3 meses após o retorno da irrigação. As variáveis diâmetro dos vasos do xilema, espessura do floema, relação entre o diâmetro polar e equatorial dos estômatos, eficiência quântica potencial do fotossistema II, conteúdo relativo de água e índice de área foliar apresentam potencial de serem utilizadas na pré-seleção de genótipos de Coffea canephora que melhor se adaptem ao manejo de irrigação utilizado no Cerrado, por possuírem relação com a variável produtividade.Item Agronomic, anatomic and physiological characterization of Coffea arabica L. genotypes on irrigated system in the Central Cerrado(Universidade Federal de Lavras, 2022-12-29) Santos, Cyntia Stephânia dos; Matos, Nagla Maria Sampaio de; Rezende, Tiago Teruel; Mauri, Janaína; Rodrigues, Gustavo Costa; Veiga, Adriano Delly; Bartholo, Gabriel Ferreira; Carvalho, Milene Alves de FigueiredoDue to climatic conditions and the possibility of using machineries, coffee has a potential to achieve high yields with reduced costs, in the biome of Cerrado. Leaf anatomy and physiology can help in the identification of more adapted cultivars to a given environmental condition. The objective is to verify the behavior of Coffea arabica L. genotypes in the Cerrado of the Brazilian Central Plateau through anatomical and physiological characterization and yield. Ten coffee genotypes from the Active Germplasm Bank located in the municipality of Planaltina, Distrito Federal, were evaluated. The genotypes evaluated were: Araponga MG1, Catiguá MG2, Catiguá MG3 P23, Catiguá MG3 P7, Catiguá MG3 P51, Catiguá MG3 P, Catuaí Amarelo IAC 62, Catuaí Vermelho IAC 15, Paraíso MG1 and Topázio MG 1190. The phenotypic characteristics evaluated were the thickness of: adaxial cuticle surface, adaxial and abaxial epidermis surfaces, the palisade and spongy parenchyma, the mesophyll layer, the phloem, number and diameter of the xylem vessels, stomatal density, relationship between the polar and equatorial diameter of the stoma, specific leaf area, stomatal conductance, transpiration rate, net photosynthetic rate, water use efficiency, intercellular carbon concentration and yield. Genotypes of Coffea arabica L. presented a distinction between the characteristics evaluated when grown under climatic conditions of the Brazilian Central Plateau Cerrado, highlighting the variations in the behavior and distinguished adaptation in this environment. The Araponga MG1 genotype stood out for anatomical and physiological characteristics of higher values, such as net photosynthetic rate, stomatal conductance, intercellular carbon concentration, abaxial and adaxial epidermis thickness, stomatal density and number of xylem vessels. The genotype Paraíso MG1 stands out for higher grain productivity. The genotype Catuaí Vermelho IAC 15 stands out for anatomical and physiological characteristics such as higher stomatal density, greater number of xylem vessels and greater efficiency in water use, resulting in improved productivity.Item Adaptations to the drought season and impacts on the yield of ‘Híbrido de Timor’ coffee tree in the Minas Gerais State Cerrado (Brazilian Savanna)(Escola de Agronomia - UFG, 2022-09-02) Santos, Cyntia Stephânia dos; Freitas, Ana Flávia de; Silva, Glauber Henrique Barbosa da; Carvalho, Milene Alves de Figueiredo; Santos, Meline de Oliveira; Carvalho, Gladyston Rodrigues; Silva, Vânia AparecidaClimate change threatens the survival of commercial crops due to their narrow genetic base. One of the alternatives is the identification of plants with potential for abiotic stress tolerance. This study aimed to verify the physiological and anatomical adaptations to the drought period and the impacts on the yield of ‘Híbrido de Timor’ coffee tree accessions. The experimental design was randomized blocks, in a 7 x 2 factorial arrangement, being seven genotypes (UFV 377-21, UFV 377-21, UFV 442-42, BE 5 Wush-Wush x UFV 366-08, UFV 428-02, UFV 376-31 and UFV 427-55) and two seasonal periods (dry and rainy), with two replications. The stomatal conductance; predawn water potential; levels of hydrogen peroxide and malondialdehyde; activity of the enzymes catalase, superoxide dismutase and ascorbate oxidase; ascorbate content; cuticle thickness of the adaxial surface and leaf lamina; stomatal density; ratio between polar and equatorial diameter; phloem area; area, diameter and frequency of xylem vessels; relative hydraulic conductivity; vulnerability index; and yield were evaluated. The results showed acclimatization of the accessions to the dry period, with some of them maintaining higher water potential values in the predawn; induction of the antioxidant system with the increase in the activity of the superoxide dismutase enzyme and ascorbate levels; increase in the cuticle and leaf lamina thickness; and a higher ratio between polar and equatorial diameters. Most of the evaluated accessions showed a good productive performance, especially the ‘UFV 377-21’, ‘UFV 442-42’ and ‘UFV 376-31’, with adaptations to the dry period and yield potential.Item Water retainer polymer in coffee plants deployment under different levels of irrigation(Editora UFLA, 2021) Resende, Thales Barcelos; Souza, Victor Hugo Silva; Castanheira, Dalyse Toledo; Carvalho, Milene Alves de Figueiredo; Guimarães, Rubens JoséThe use of water-retaining polymers may be a feasible alternative in regions with low water availability, as they has enhance the performance of coffee plants with more favorable anatomical characteristics to make physiological processes more efficient. However, the advantages of such use have been scarcely reported. Here, we studied the feasibility of using a water-retaining polymer to optimize irrigation water use during the establishment of a coffee plantation. A randomized block design was used in a factorial scheme (4 × 2) with three replications for a total of 24 experimental plots, each consisting of four pots, with one plant per unit. The experiment was installed in a greenhouse at the Coffee Science Department of the Universidade Federal de Lavras, Minas Gerais, Brazil, with four levels of irrigation (25%, 50%, 75%, and 100% of soil water at field capacity), with or without addition of the water-retaining polymer. Growth variables evaluated included: plant height, stem diameter, number of leaves, shoot and root dry weights, root volume and area. Additionally, gas exchange, leaf water potential, and leaf anatomy were analyzed. The use of water-retaining polymer during establishment of the coffee plantation ensured sufficient water supply, thus guaranteeing plant anatomical and physiological functionality and, consequently, a healthy, vigorous growth.Item Leaf anatomy, physiology and vegetative growth of fertigated Coffee arabica L. trees after exposure to pruning(Editora UFLA, 2021) Soares, Daiane dos Santos; Silva, Elisângela Aparecida da; Carvalho, Milene Alves de Figueiredo; Pereira, Fernanda Aparecida Castro; Guimarães, Rubens JoséIn coffee plants, fertigation can be an alternative way to minimize the negative effects exerted by drought and maximize fertilizer use efficiency. However, the fertilization recommendations for fertigated coffee trees are still not very specific, and the recommendations for rainfed crops are used. In addition, little is known about the nutritional requirements for fertigated coffee trees that have undergone the low recepa pruning treatment. Thus, the objective of this study was to evaluate the effects of different levels of nitrogen (N), phosphorus (P), and potassium (K) fertilizers on leaf anatomy, physiology, and veg etative growth of fertigated coffee trees (Coffea arabica L.) that have been under the low recepa pruning treatment. During the first five years of growth, the cultivar Topázio MG-1190 of the coffee crop received 10, 40, 70, 100, 130, and 160% of the fertilization levels recommended for the rainfed coffee crop. After this period, the crop was exposed to low recepa pruning. It was concluded that different doses of N, P, and K fertilizers modified the internal structure of coffee plant leaves, as well as physiological responses and plant growth; there was stronger vegetative growth, sharper leaf blade, greater thickness of spongy parenchyma, larger phloem area, and higher xylem relative hydraulic conductivity as the N, P, and K fertilizer levels in fertigated coffee (Coffea arabica L.) plants, which received the low recepa pruning treatment, increased. This knowledge can be used as a solid basis for main fertilization recommendations for fertigated coffee trees after exposure to the low recepa pruning treatment.Item Coffee genotypes morphophysiological adaptation under coffee leaf rust biotic stress(Editora UFLA, 2021) Viana, Mariana Thereza Rodrigues; Azevedo, Harianna Paula Alves de; Pereira, Fernanda Aparecida Castro; Carvalho, Milene Alves de Figueiredo; Guimarães, Rubens JoséThe identification of morphophysiological traits responsible for a better plant behavior when infected is useful for cultivar selection, and become crucial for breeding. We investigated the morphophysiological behavior of coffee genotypes before and after inoculation with the pathogen Hemileia vastatrix, causal agent of coffee rust. With multivariate techniques we identified the characteristics that most contribute to total genetic divergence of the geno types. Ten genotypes of Coffea arabica from the Germplasm Bank of Coffee from Minas Gerais were sown in a nursery and then take to a greenhouse with controlled temperature and humidity. After one month of acclimatization, the artificial inoculation with the fungus H. vastatrix was carried out. The anatomical and physiological evaluations were performed 1 day before inoculation and 160 days after inoculation. When the first symptom emerged, plants were evaluated according to a descriptive scale for coffee rust. We observed significant differences in rust severity and ostiole opening between genotypes. Different groups were formed by the K-means method, based on morphophysiological characteristics. This shows that genetic variability exists between the coffee genotypes evaluated before and after inoculation with the pathogen. The most important characteristics that contributed to the total genetic divergence were xylem vessel diameter and stomatal conductance. In conclusion, inoculation with H. vastatrix caused a change in coffee geno types based on morphophysiological characteristics.