Navegando por Autor "Castro, Elisa de Melo"

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Desempenho agronômico de populações de cafeeiros do grupo ‘Bourbon’
(Editora UFLA, 2016-01) Lima, Amador Eduardo de; Mendes, Antônio Nazareno Guimarães; Carvalho, Gladyston Rodrigues; Botelho, César Elias; Castro, Elisa de Melo; Cardoso, Diego de Abreu
A seleção de materiais genéticos de cafeeiros influencia diretamente na obtenção de genótipos mais produtivos e com alta qualidade de bebida. Objetivou-se, com este trabalho, avaliar, em duas regiões do estado de Minas Gerais, características agronômicas de cafeeiros do grupo Bourbon, com potencial para produção de cafés especiais, visando à seleção de populações com alta produtividade, adaptadas e estáveis. Foram avaliados 20 tratamentos, sendo 17 populações de cafeeiros do grupo Bourbon e três cultivares amplamente cultivadas no Brasil. Utilizou-se o delineamento em blocos casualizados (DBC), com três repetições e cada parcela foi composta por dez plantas. Avaliaram-se as características de produtividade de grãos, porcentagem de grãos com peneira 16 e acima, vigor vegetativo, adaptabilidade e estabilidade nos três locais em estudo (Lavras, Três Pontas e Patrocínio). As populações estudadas apresentam maior potencial produtivo na região Sul de Minas, representada pelos municípios e Lavras e Três Pontas do que na região do Alto Paranaíba. As populações 05 (Bourbon Amarelo - Faz. Boa Vista / Campos Altos – MG), 17 (Bourbon Amarelo - Faz. Monte Alegre - Talhão Limoeiro / Alfenas - MG) e 19 (Catuaí Vermelho IAC 144 - Faz. Experimental de Machado - MG), mostram-se mais produtivas, adaptadas e estáveis. A alta produtividade aliada a outras características agronômicas de interesse, apresentadas pelas populações de café Bourbon, evidenciam o seu alto potencial para seleção.
Incidence and severity of coffee leaf rust, cercosporiosis and coffee leaf miner in coffee progenies
(Editora UFLA, 2018-07) Lima, Amador Eduardo de; Sampaio Junior, Hudinilson Gilberto; Castro, Elisa de Melo; Carvalho, Samuel Pereira de; Silva, Fabiano França da; Lima Junior, Sebastião de; Carvalho, Alex Mendonça de
Coffee leaf rust is the main disease of this crop, however cercosporiosis and coffee leaf miner can also cause significant damage when they reach high levels of infestation. Plant genetic improvement for resistance is one of the best tools for controlling plant diseases. The objective in this work was to identify F 3 progenies of Coffea arabica with resistance to coffee leaf rust, which present a lower incidence and severity of cercosporiosis and coffee leaf miner. The treatments were constituted by 10 progenies, besides two cultivars coffee leaf rust susceptible, used as a control. The experimental design was a randomized block design (RBD), with two replicates, each block consisting of 12 plots randomly distributed, each corresponding to one treatments. The following characteristics were evaluated: coffee leaf rust intensity and severity, cercosporiosis and coffee leaf miner, plants vegetative vigor, grain maturity uniformity and plants height. The progeny averages were grouped by the Scott & Knott test at 5% probability. Progenies 27, 30 and 15 were selected, since they presented low incidence in relation to coffee leaf rust, cercosporiosis and coffee leaf miner, and will be used to continue the breeding program.
Production of Coffea canephora seedlings through cuttings in a nursery and hydroponics using different containers
(Universidade Federal de Lavras, 2023-07-19) Lima, Amador Eduardo de; Castro, Elisa de Melo; Cunha, Samuel Henrique Braga da; Guimarães, Rubens José; Chalfun, Nilton Nagib Jorge; Carvalho, Alex Mendonça de; Alves, Eduardo; Carvalho, Milene Alves Figueiredo
The production of seedlings is a determining factor for the establishment and success of the coffee plantation. The objective of this study was to evaluate the production of Coffea canephora seedlings by cuttings in a modified hydroponic system and in a conventional nursery, using different containers. At the end of the experiment, growth (height, stem diameter, total number of pairs of leaves, leaf area, root area, dry matter weight of leaves, stem and root), physiological (chlorophyll a, b and total and stomatal conductance) and anatomical (stomatal density, functionality and opening) characteristics were analyzed. For statistical analysis, a completely randomized design (CRD) was used, with five treatments and six replications, with ten plants per plot. Seedlings produced in a modified hydroponic system using 50- and 120-cm³ tubettes show better vegetative growth and physiological characteristics compared to those produced in a nursery. Seedling management in a modified hydroponic system using 120-cm³ tubettes provides greater cutting survival percentage, number of remaining leaves and emission of shoots. In nurseries, the use of polyethylene bags provides better seedling quality and survival in relation to the use of tubettes, regardless of volume.
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).
Ultrastructural damage in coffee seeds exposed to drying and to subzero (°C) temperatures
(Editora UFLA, 2020) Coelho, Stefânia Vilas Boas; Rosa, Sttela Dellyzete Veiga Franco da; Clemente, Aline da Consolação Sampaio; Lacerda, Laura Nardelli Castanheira; Silva, Luciano Coutinho; Fantazzini, Tatiana Botelho; Ribeiro, Fernando Augusto Sales; Castro, Elisa de Melo
During drying and freezing, protective mechanisms act to maintain seed physiological quality. Some of these mechanisms contribute to the integrity of cell membranes. The damage caused to cell membranes due to cell stress can be seen in ultrastructural studies, comparing these results to those of physiological evaluation. The aim of this study was to investigate ultrastructural changes in endosperm cells of coffee seeds brought about by drying and by exposure to low temperatures. Seeds of Coffea arabica were dried in silica gel to moisture contents of 40, 20, and 5 % (wb) and brought to equilibrium at temperatures of 10, -20, and -86 oC. Germination, vigor, and tetrazolium tests were performed for evaluation of seed physiological quality. Ultrastructural damage was analyzed by scanning electron microscopy. Coffee seeds with 40% moisture content have whole, swollen, and expanded cells, with a filled lumen and without signs of damage. The physiological and ultrastructural quality of seeds exposed to below zero temperatures with 40% moisture content is compromised. They have null germination and empty cells, indicating leakage of cell content. Drying of coffee seeds leads to uniform contraction of inner cell content. Drying of coffee seeds to 5% moisture content leads to intense contraction of cell volume, with physiological and ultrastructural damage.