Ciência e Agrotecnologia

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/9885

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Resultados da Pesquisa

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    Trolox equivalent antioxidant capacity of Coffea arabica L. seeds
    (Editora UFLA, 2022-08-08) Ferreira, Iara Alves; Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Vilas Boas; Ricaldoni, Marcela Andreotti; Costa, Marina Chagas
    The causes of the low desiccation tolerance and low longevity of coffee seeds have not yet been fully elucidated, and a full understanding of their complex physiology is of great interest. Among several alternatives, the loss of antioxidant capacity in seeds may be related to their rapid loss in quality during storage. The objective of this study was to determine the total antioxidant capacity of coffee harvested at different ripeness stages before and after the storage of seeds with different water contents and to relate antioxidant capacity to physiological quality. Seeds in the greenish-yellow or cherry stages, recently harvested or stored for nine months at 10 °C with 40, 30, 20 and 12% water content (wet basis - wb), were submitted to physiological and biochemical quality evaluations, and the Trolox equivalent antioxidant capacity (TEAC) was determined. The germination and root protrusion of coffee seeds from greenish-yellow and cherry fruits were not affected by drying, but seeds harvested at physiological maturity had greater vigor when the moisture content was lower. The quality of coffee seeds decreased during storage, and this decrease was greater in seeds stored with higher water contents. Coffee seeds in the greenish-yellow stage had a higher antioxidant capacity than those in the cherry stage when recently harvested, but there was a substantial reduction in this capacity during storage at both maturation stages. Coffee seed deterioration is related to a reduction in antioxidant capacity, and the isoenzymatic profiles of the antioxidant process are little affected by the seed maturation stage. The deterioration of coffee seeds during storage is related to a reduction in their total antioxidant capacity, regardless of their maturation stage, being more pronounced in the greenish-yellow stage
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    Seedling production of Coffea arabica from different cultivars in a modified hydroponic system and nursery using different containers
    (Editora UFLA, 2021-11-22) Lima, Amador Eduardo de; Guimarães, Rubens José; Cunha, Samuel Henrique Braga da; Castro, Elisa de Melo; Carvalho, Alex Mendonça de; Faria, Mauro Magalhães Leite
    The development of modified hydroponic cultivation has aroused interest and its use has enabled advantages in several crops, but studies for coffee are still scarce. Thus, the objective of this research was to evaluate seedling production of three Coffea arabica cultivars (Mundo Novo IAC-376-4, Catuaí IAC-62 Amarelo and MGS Paraíso 2), in a modified hydroponic system, and to compare it with the nursery production system, using plastic polyethylene tubettes and bags. Coffee seedlings in the development phase with cotyledon leaves, were cultivated in both cultivation systems. At 90 days after the implementation of the experiment, the seedlings were analyzed for growth (height, stem diameter, total number, leaf area, root area, root and shoot dry matter weight), and physiological characteristics (chlorophyll content and stomatal conductance). For the statistical analysis, a completely randomized design (CRD) was used in a factorial scheme 3 (cultivars) x 2 (containers) x 2 (cultivation systems), with four replications of ten plants per plot. The innovative production system of coffee seedlings in modified hydroponics, in combination with the use of polyethylene bags, provided greater growth of coffee seedlings with better physiological characteristics. Among the cultivars tested, MGS Paraíso 2 stood out with higher seedling growth (number of leaves, stem diameter and root and shoot dry matter weight).