Biblioteca do Café
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1
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Resultados da Pesquisa
Item Respuesta fotosintética de Coffea arabica L. a diferentes niveles de luz y disponibilidad hídrica(Universidad Nacional de Colombia, 2014) Mariño, Yesid AlejandroEl sombrío permite una mejor aclimatación del café (Coffea arabica L.) en zonas donde el invierno se caracteriza por bajas temperaturas nocturnas seguido de días soleados y el verano, por altas tempera turas y lluvias ocasionales. En este estudio, realizado en Viçosa-MG, Brasil, se analizaron los efectos de dos condiciones de luminosidad (pleno sol y 15% de la radiación solar) y disponibilidades de agua en el suelo sobre las relaciones hídricas y el desempeño fotosintético en C. arabica en dos épocas con trastantes. Independientemente de la época de evaluación, las plantas cultivadas en condiciones de baja disponibilidad hídrica presentaron reducciones en la fotosíntesis (A), conductancia estomática (gs) y en la razón Ci/Ca en los dos tratamientos lumínicos. Estos cambios fueron acompañados con la reducción en la conductancia hidráulica y la transpiración. No se presentaron diferencias significativas en la producción cuántica efectiva, en el coeficiente de extinción no-fotoquímica y en la productividad cuántica basal de los procesos no fotoquímicos. Sobre la disponibilidad hídrica adecuada, las plantas cultivadas al sol presentaron reducciones en A, gs y Ci/Ca en la época de invierno. Adicionalmente, se encontraron limitaciones fotoquímicas con la reducción en la razón de las fluorescencias variable e inicial. Los resultados indican que cualquier recomendación de uso de sombrío como práctica de manejo debe ser tomada con precaución.Item Implications of the cut type and apex length of stem cuttings used for the production of plantlets of Conilon coffee(Editora UFLA, 2020) Verdin Filho, Abraão Carlos; Freitas, Silvio de Jesus; Comério, Marcone; Volpi, Paulo Sérgio; Colodetti, Tafarel Victor; Rodrigues, Wagner Nunes; Fonseca, Aymbiré Francisco Almeida da; Posse, Sheila Cristina Pruculi; Fontes, Alexandre Gomes; Christo, Bruno Fardim; Vieira, Luciano Junior DiasProducing plantlets of Conilon coffee within the specific recommendations and with a high level of quality is fundamental since it is capable of promoting the initial development of the crops. To identify the best protocol to prepare the stem cuttings is fundamental to the process of plantlet production of the species. In this context, this study aimed to evaluate the implications of the type of apex cutting and the length of the remaining apex of stem cuttings to produce plantlets of Conilon coffee (Coffea canephora). To this end, two trials were conducted in the Marilândia Experimental Farm (Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural, Marilândia-ES). The first trial evaluated the types of apex cutting (straight or bevel cut), and the second trial studied the different lengths of the remaining apex (0.5, 1.0, 1.5, 2.0, and 2.5 cm). Characteristics of the vegetative growth and photosynthetic traits of the plantlets of Conilon coffee were evaluated after 120 days of cultivation in a nursery. The biomass accumulation of the plantlets of Conilon coffee produced by stem cutting may be favored by the use of bevel cut on the apex. The length of the remaining apex does not seem to have a expressive effect over the quality or growth of the plantlets, being only possible to observe effects for leaf area and biomass accumulation.Item Physiological responses of Coffea arabica cultivars in association with arbuscular mycorrhizal fungi(Editora UFLA, 2020) Cruz, Rafaele de Sousa; Araújo, Fausto Henrique Vieira; França, André Cabral; Sardinha, Levy Tadin; Machado, Caroline Maira MirandaThe inoculation of coffee plants with arbuscular mycorrhizal fungi (AMF) may influence some of its physiological parameters, promoting benefits in the growth of newly planted coffee. The objective of this work was to evaluate the physiological responses of different cultivars of Coffea arabica inoculated with arbuscular mycorrhizal fungi. The experiment was conducted in a vegetation house in Diamantina, state Minas Gerais. The design was in randomized blocks, in a 3 x 4 factorial scheme, with four replications. The factors were composed of coffee seedlings of Rubi (MG 1192), Mundo Novo (IAC 379-19) and Catuaí Vermelho (IAC 144) cultivars, inoculated or not with FMA Rhizophagus clarus, Acaulospora colombiana and Mix composed by R. clarus and A. colombiana. At 150 days after transplantation, physiological characteristics such as photosynthetic rate, internal carbon concentration, stomatal conductance, transpiration rate, water use efficiency, internal carbon / atmospheric carbon ratio and percentage of mycorrhizal colonization were evaluated. AMF inoculation affected positively the physiology of coffee plants, increasing photosynthetic rate (A), stomatal conductance (Gs), transpiration, carbon consumed (ΔCO2), water use efficiency (EUA) and percentage of mycorrhizal colonization (%), as well as reducing the internal carbon concentration (Ci) for all combinations of AMF cultivars and species. The cultivar Rubi, when inoculated with R. clarus or Mix, obtained a higher percentage of colonization. The physiological activity of coffee plants is altered by symbiotic association, and their responses varied between AMF species and cultivars.