Biblioteca do Café
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1
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Item Morphological, physiological, and agronomic traits of crossings of 'Icatu' x 'Catimor' coffee tree subjected to water deficit(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2022-07-27) Coelho, Larissa Sousa; Tassone, Guilherme Augusto Teixeira; Carvalho, Gladyston Rodrigues; Silva, Vânia Aparecida; Viana, Mariana Thereza Rodrigues; Pereira, Fernanda Aparecida Castro; Nadaleti, Denis Henrique Silva; Silveira, Helbert Rezende de Oliveira; Botelho, Cesar EliasThe objective of this work was to select genotypes of Coffea arabica with good yield and potential tolerance to water deficit, as well as to try to understand the physiological and anatomical mechanisms involved in the adaptability of these genotypes to water stress. The physiological, anatomical, and agronomic traits of 19 genotypes of C. arabica were evaluated under the two following water conditions: regular irrigation and no irrigation (soil water deficit). The 'IPR 100', 2, 5, and 7 genotypes showed agronomic, physiological, and anatomical traits that contributed to a better water status maintenance in the initial development of coffee plants. Based on these results, these genotypes are potentially tolerant to water deficit. The 4, 10, 11, 14, 15, and 'Bourbon Amarelo IAC J10' genotypes show a lower adaptability of the anatomical structures under soil-water deficit conditions. The coffee tree genotypes display leaf plasticity, such as the thickness of palisade and spongy parenchyma, and the number, position, dimensions, and mobility of stomata under water deficit conditions.Item Coffee genotypes morphophysiological adaptation under coffee leaf rust biotic stress(Editora UFLA, 2021) Viana, Mariana Thereza Rodrigues; Azevedo, Harianna Paula Alves de; Pereira, Fernanda Aparecida Castro; Carvalho, Milene Alves de Figueiredo; Guimarães, Rubens JoséThe identification of morphophysiological traits responsible for a better plant behavior when infected is useful for cultivar selection, and become crucial for breeding. We investigated the morphophysiological behavior of coffee genotypes before and after inoculation with the pathogen Hemileia vastatrix, causal agent of coffee rust. With multivariate techniques we identified the characteristics that most contribute to total genetic divergence of the geno types. Ten genotypes of Coffea arabica from the Germplasm Bank of Coffee from Minas Gerais were sown in a nursery and then take to a greenhouse with controlled temperature and humidity. After one month of acclimatization, the artificial inoculation with the fungus H. vastatrix was carried out. The anatomical and physiological evaluations were performed 1 day before inoculation and 160 days after inoculation. When the first symptom emerged, plants were evaluated according to a descriptive scale for coffee rust. We observed significant differences in rust severity and ostiole opening between genotypes. Different groups were formed by the K-means method, based on morphophysiological characteristics. This shows that genetic variability exists between the coffee genotypes evaluated before and after inoculation with the pathogen. The most important characteristics that contributed to the total genetic divergence were xylem vessel diameter and stomatal conductance. In conclusion, inoculation with H. vastatrix caused a change in coffee geno types based on morphophysiological characteristics.Item Simultaneous selection in coffee progenies of mundo novo by selection indices(Editora UFLA, 2019-01) Tasson, Guilherme Augusto Teixeira; Nadaleti, Denis Henrique Silva; Carvalho, Gladyston Rodrigues; Pereira, Fernanda Aparecida Castro; Andrade, Vinícius Teixeira; Botelho, César EliasCoffee cultivars that are better adapted and more productive can help reduce production costs and make coffee cultivation more profitable. The Mundo Novo cultivar has stood out as one of the most productive cultivars of Coffea arabica L. Therefore, the aim of this work was to select Mundo Novo progenies with high bean yield capacity and with other agronomic characteristics of interest. We evaluated the bean yield, seed size, plant height, upper and lower canopy diameter, stem diameter, and plant vigor of 24 F 4 progenies and one check cultivar. The experimental design consisted of a randomized complete block design with three replicates and experiments were carried out in two sites: São Sebastião do Paraíso (SSP) and Três Pontas (TP), MG, Brazil. The mixed model approach was used to calculate the genotypic value for each progeny, after which the selective accuracy and genetic gain of the two best progenies in each trait were calculated, the simultaneous selection index of Mulamba and Mock was used to select the two most promising progenies at each site. In general, the genetic gain was higher at SSP than at TP. In SSP, the most promising progenies were 1 [IAC376-2 (M. Novo) x IAC386-17 (M. Novo)] and 20 [IAC382-10 (M. Novo) x IAC388-20 (M. Novo)]. In TP, the most promising progeny was 22 [H1535/181 (M. Novo) x (S795) 1344/10/5], together with the check (Mundo Novo IAC379/19). The highest selection gain was expressed for bean size (the percentage of beans retained in sieve 17).Item Selection of coffee progenies with large beans resistant to rust and cercospora leaf spot(Editora UFLA, 2019-01) Pereira, Fernanda Aparecida Castro; Carvalho, Samuel Pereira de; Viana, Mariana Thereza Rodrigues; Vidal, Douglas Alves; Ferreira, Guilherme Souza; Silva, Joyce Alves Goulart da; Sâmia, Michelly PereiraRust is the main disease of coffee. Recently, cercospora leaf spot has grown in importance, intensifying defoliation and decreasing grain yield in Coffea arabica. The Big Coffee VL is a variety of C. arabica, with large beans. There is still little information on this variety. Because of this, the aim of this study was to use a mixed model approach to select the best progenies of “Big Coffee VL” for resistance to rust and cercospora leaf spot. There were evaluated 12 progenies with high bean yields. Based on bean size, leaves and plant size, plants within each progeny were classified as “small” (P), “medium” (M) and “large” (G). The experimental design was in blocks completely randomized, with six replicates and one plant per plot. Six measurements were carried out every 15 days for each plant by selecting 20 fully exposed leaves with higher and lower sun exposures. The measurements summarized disease severity using two diagrammatic scales to obtain the area of the leaf under rust or Cercospora leaf spot. A mixed model approach was used to calculate genotypic value (GV) and heritability estimates. The Mulamba and Mock index was used to select the most resistant progenies, in which the sum of rankings was weighted by a heritability value. Five progenies were selected; three progenies were G (G17, G9, and G12), one progeny was M (M5) and another progeny P (P23). Among these, M5 and P23 progenies are the most productive and may have potential use in future studies. This work presents the potential in investigating the new C. arabica variety.