Periódicos
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item 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 ChagasThe 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 stageItem Influence of nitrogen fertilization in mother plants on the growth and quality of clonal seedlings of Coffea canephora ‘Robusta’ plants(Universidade Federal de Santa Maria, 2022-01-31) Kolln, Alana Mara; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Campanharo, Marcela; Rocha, Rodrigo Barros; Lourenço, João Luiz ResendeThe nutritional management of the coffee clonal garden influences the production and physiological quality and seedlings production of vegetative propagules. Thus, this study aimed to analyze the seedlings’ production from clonal cuttings taken from Coffea canephora mother plants grown with increasing nitrogen mineral doses. The cuttings were taken from C. canephora var. botany Robusta, from the Embrapa Genetic Improvement Program of Rondônia. The mother plants received nitrogen fertilizer at different doses: 0 (Control); 50; 100; 150; 200; 250 and 300 kg of N per hectare divided into 4 applications, during 150 days of orthotropic stems growth (shoots). The following parameters were evaluated: Dry mass of cuttings, nutritional content of cuttings, and seedlings production, with growth analysis at 0, 48, 61, 80, 101, 122, 143, and 164 days after staking (DAS) and analysis of vegetative characteristics at 122 DAS. The nitrogen fertilization in the mother plant resulted in the variation of macronutrient accumulation in cuttings, but the order K> N> Ca> P> Mg> S was maintained, regardless of N dose. In addition, a positive correlation between nitrogen doses and dry matter accumulation, as well as the physiological quality of seedlings was identified.