Biblioteca do Café
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1
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Item Nutritional balance and its relationship to yield in a coffee field: Inferences from geospatial analysis(Departamento de Engenharia Agrícola - UFCG, 2020) Silva, Marcelo B. da; Partelli, Fábio L.; Gontijo, Ivoney; Caldas, Marcellus M.Information obtained from studies of spatial variability and the Diagnosis and Recommendation Integrated System (DRIS) may contribute to understanding better the relationship between mineral nutrient balance and factors that limit the crop yield. This study shows that nutritionally balanced plants may be associated with low productivity in Conilon coffee fields. The study was carried out on a highly productive Conilon coffee (Coffea canephora) field, in São Mateus, state of Espírito Santo, Brazil. A sample grid was established with 100 points, each point linked to one plant. Twenty pairs of leaves from each plant were collected from productive branches to create a sample for nutritional analysis. The rust incidence (Hemileia vastatrix), the presence of the coffee borer (Hypothenemus hampei), and the physical characteristics of the soil were evaluated in each sampled plant. DRIS and Nutrient Balance Index (NBI) were calculated, and from the yield data, they were characterized using descriptive statistics. Maps were created showing the spatial distribution of the NBI, yield, total sand, and incidence of rust and coffee borer. It was verified the low relationship between nutritional balance and yield in Conilon coffee, suggesting that non-nutritional factors also influenced plant production. In areas of the maps with high NBI, the plant’s nutritional balance was the main limiting factor of production, since most plants in this area produced less than the average productivity of the plants sampled. The use of a geostatistics tool combined with the NBI resulted in better understanding of the relationship between nutritional and non-nutritional variables on the Conilon coffee yield.Item Nutritional diagnosis by dris method of the cultivars coffee in the northern region of Paraná, Brazil(Editora UFLA, 2015-04) Silva, Ricardo Augusto da; Creste, José Eduardo; Tiritan, Carlos Sérgio; Guerra, Wellington Eduardo Xavier; Ecker, Arney Eduardo do Amaral;Due to the lack of knowledge on the nutritional status of the coffee shrub, DRIS method was introduced in coffee culture in the northern region of the state of Parana, Brazil. Current research aimed at establishing a data base for DRIS guidelines in coffee culture and introducing other parameters for the rational and balanced application of fertilizers. Assay was performed between February 2011 and February 2012 (Harvest 2011/201) in coffee plantations in the municipality of Pitangueiras PR Brazil, 23 o 14’ 03” S and 51 o 35’ 06” W; altitude 600 m. Leaf samples from 75 coffee shrub lots were retrieved from 69 plantations, featuring cultivars IAPAR 59, IPR 98, IPR 99, Catuaí, Mundo Novo and Tupi. DRIS norms were established for the nutritional diagnosis of the coffee shrub for the northern region of the state of Paraná through the criterion of productivity at 55 sacks ha -1 . Data revealed that potassium constituted the highest deficiency, followed by Cu and Zn. Fe, S and Mn had excessive rates with regard to parameters at regional level.Item Characterization and quantitative expression analysis of a putative Metallothionein-like gene in Coffea arabica under zinc supply(Universidade Federal de Lavras, 2012-10-19) Barbosa, Bárbara Castanheira Ferrara; Chalfun Júnior, AntonioO zinco foi identificado como um nutriente essencial para as plantas nos anos 1970. Em plantas, ele é absorvido na forma Zn 2+ , e as suas funções estão relacionadas com as propriedades de um cátion bivalente, com uma forte tendência para formar complexos tetraédricos. O zinco age quer como componente metálico de enzimas ou como cofatores. Por exemplo a álcool desidrogenase, superóxido dismutase, anidrase carbónica e RNA polimerase são enzimas que contêm Zn. O zinco também exibe um papel na ativação de enzimas envolvidas no metabolismo de carboidratos, proteínas, triptofano e ácido indol-acético (AIA). Acredita-se que as metalotioneínas (MTs), proteínas conhecidas por participar no processo de homeostase de metais, são parcialmente responsáveis pela absorção de zinco em plantas. Metalotioneínas são proteínas de baixo peso molecular, ricas em resíduos de cisteína que podem se ligar a metais, formando compostos do tipo metal-tiolato. Em contraste com os numerosos relatórios sobre a estrutura gênica e padrões de expressão, as funções das MTs não foram precisamente determinadas. Dessa forma, este estudo objetivou caracterizar in silico os prováveis genes que codificam metalotioneínas e analisar a expressão de alguns destes genes em resposta ao fornecimento de zinco em café. As sequências selecionadas obtidas a partir das pesquisas realizadas no banco de dados CAFEST tiveram a sua filogenia avaliada por árvores filogenéticas e seus perfis de expressão in silico foram analisados por Northerns eletrônicos. O banco de dados CAFEST mostrou um elevado número de sequências relacionadas com metalotioneínas. As árvores filogenéticas demonstraram uma elevada similaridade entre as sequências encontradas no CAFEST e as sequencias de outras espécies, e os Northerns eletrônicos detectaram a sua expressão em diferentes tecidos, fases de desenvolvimento e condições de stress. As análises quantitativas de expressão dos genes que codificam MTs mostraram que estes genes são expressos diferencialmente em resposta às diferentes doses de zinco fornecidas.