Periódicos

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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Resultados da Pesquisa

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    Influence of humus on chromium absorption by coffee seedlings grown on substrate containing tannery sludge
    (Universidade Federal de Viçosa, 2023-03-10) Berilli, Sávio da Silva; Oliveira, Dhiego da Silva; Martineli, Leonardo; Pereira, Lucas Louzada; Cunha, Maura da; Pireda, Saulo
    Chromium is present in the tannery sludges worldwide making it a problem for agriculture. This study aimed to evaluate whether humus functions as a chromium stabilizing agent when using tannery sludge in the substrate of conilon coffee seedlings (Coffea canephora) and to determine what effects there are on leaf development and anatomy. Treatments consisted of a fixed dose of tannery sludge (30% of volume) on substrates of conilon coffee seedlings with different proportions of humus and subsoil (T-10, T-20, T-30, T-40% of humus). Information for the evaluation of leaf anatomy and seedling development was collected at 180 days after the planting of cuttings. From the phenological point of view, the treatments that best promoted seedling quality were T-30 and T-40. However, the greater the amount of humus in the substrate the greater the absorption of chromium by plants, which directly affected the organization of epidermal cells and leaf mesophyll. In addition, intense cytoplasmic degradation, ultrastructural changes in chloroplasts and mitochondria, and an increase in autophagic vacuoles were observed. We conclude that increasing the amount of humus in substrate with tannery sludge provides higher quality coffee seedlings, despite promoting greater absorption of chromium by plants and the consequent major intracellular disturbances.
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    Morphological, physiological, and agronomic traits of crossings of 'Icatu' x 'Catimor' coffee tree subjected to water deficit
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2022-07-27) Coelho, Larissa Sousa; Tassone, Guilherme Augusto Teixeira; Carvalho, Gladyston Rodrigues; Silva, Vânia Aparecida; Viana, Mariana Thereza Rodrigues; Pereira, Fernanda Aparecida Castro; Nadaleti, Denis Henrique Silva; Silveira, Helbert Rezende de Oliveira; Botelho, Cesar Elias
    The objective of this work was to select genotypes of Coffea arabica with good yield and potential tolerance to water deficit, as well as to try to understand the physiological and anatomical mechanisms involved in the adaptability of these genotypes to water stress. The physiological, anatomical, and agronomic traits of 19 genotypes of C. arabica were evaluated under the two following water conditions: regular irrigation and no irrigation (soil water deficit). The 'IPR 100', 2, 5, and 7 genotypes showed agronomic, physiological, and anatomical traits that contributed to a better water status maintenance in the initial development of coffee plants. Based on these results, these genotypes are potentially tolerant to water deficit. The 4, 10, 11, 14, 15, and 'Bourbon Amarelo IAC J10' genotypes show a lower adaptability of the anatomical structures under soil-water deficit conditions. The coffee tree genotypes display leaf plasticity, such as the thickness of palisade and spongy parenchyma, and the number, position, dimensions, and mobility of stomata under water deficit conditions.
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    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 Aparecida
    Climate 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.