Coffee Science_v.15, 2020

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12726

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 4 de 4
  • Imagem de Miniatura
    Item
    Identification of acid-tolerant coffee genotypes in a coffee germplasm collection of Colombia
    (Editora UFLA, 2020) Acuña-Zornosa, Ricardo; Sadeghian-Khalajabadi, Siavosh
    One of the limitations of coffee production in many regions of Colombia is the soil acidity. According to historical soil chemical analysis records, more than 50% of coffee farms have pH values below 5.0. Because acid-tolerant coffee varieties are not available, farmers use calcareous additives to correct the problem, which incurs associated labor and input costs. The objective of this work was to identify acid-tolerant genotypes of Coffea arabica. For two contrasting soils in the coffee-growing area of Colombia (Andisol and Entisol), the effect of soil acidity on the growth of 20 genotypes of Coffea Arabica during the seedling stage was evaluated. The genotypes were wild accessions that make up the Colombian Coffee Germplasm Collection and the Castillo ® Naranjal Variety, used as commercial material. Six months after the seedlings were transplanted into soils treated with or without acidity correction additives, the weight of the dry matter of the roots, stems and leaves was recorded. Later, the acid-tolerant genotypes were identified by means of the quadrant method and the tolerance index. The Timor Hybrid and Rume Sudan genotypes were identified as tolerant of the acidity of the two soil types. These genotypes could be used as progenitors in a coffee breeding program leading to a commercial coffee variety tolerant to soil acidity.
  • Imagem de Miniatura
    Item
    Resistance of new Coffea canephora clones to root-knot nematode (Meloidogyne incognita) in the western amazon
    (Editora UFLA, 2020) Rudnick, Vaneide Araújo de Sousa; Vieira Junior, José Roberto; Fernandes, Cleberson de Freitas; Rocha, Rodrigo Barros; Teixeira, Alexsandro Lara; Ramalho, André Rostand; Espindula, Marcelo Curitiba; Santos, Anderson Vieira; Anjos, Elize Francisca Mendes dos; Uchôa, Francisco Paiva
    Root-knot disease is among the main diseases affecting coffee crop. The plant selection to the development new resistant cultivars is among one the most efficient methods of control. The present work aimed to quantify the resistance responses of Coffea canephora clones to root-knot nematode Meloidogyne incognita in the Western Amazon. For this, 17 previously selected clones were evaluated in three experimental trials, carried out in the municipalities of Ji-Paraná and Porto Velho, Rondônia. The resistance to root-knot nematodes M. incognita were evaluated by the numbers of gall in the roots (NG) and by the reproductive factor (RF). The resistance response was also interpreted according the genetic diversity of the clones based in their morphological traits. The clones BRS3210, C12, BRS2314, BRS3137 and BRS1216 are resistant to M. incognita with RF of 0.34, 0.62, 0.79, 0.86 and 0.98, respectively. BRS3213, C125, C15, BRS2336, BRS3220 and C09 clones were classified as susceptible, with RF of 1.93, 1.95, 2.00, 2.31, 2.32 and 2.35. The BRS3193, C160 and BRS2357 clones were classified as very susceptible, with RF values of 3.03, 4.41 and 5.82, respectively. The clustering based on the genetic diversity of morphological traits indicated that genotypes more similar to the Robusta botanic variety had lower RF. The hybrid plants showed intermediate degrees of resistance indicating the segregation for the character of the M. incognita resistance. The clones BRS3210, C12, BRS2299, BRS2314, BRS3137 and BRS1216 expressed resistance responses to M. incognita with potential for growing resistant genotypes in the Western Amazon.
  • Imagem de Miniatura
    Item
    Agronomic performance of coffee in response to framework pruning in cycles of the “safra zero”
    (Editora UFLA, 2020) Maia, Pedro Lage; Tassone, Guilherme Augusto Teixeira; Nadaleti, Denis Henrique Silva; Botelho, Cesar Elias; Botelho, Deila Magna dos Santos; Moreira, Priscila Carvalho; Carvalho, Gladyston Rodrigues
    In this paper, we aimed at selecting genotypes of Coffea arabica L. that are responsive to framework pruning, with high productive potential and desirable agricultural features. We evaluated 18 progenies in the F5 generation, 8 of them being from the group Catucaí (breeding of seedlings of Red Catuaí with coffee seeds of the Icatu germplasm) and ten descendants from the Timor Hybrid (breeding of the Red and Yellow Catuaí with the Timor Hybrid), as well as two commercial cultivars as control (Tupi IAC 1669-33 and Obatã IAC 1669-20). The experiment was carried out at the experimental field of the Federal University of Lavras. The coffee was pruned in August 2014 after the sixth crop and once again in August 2016, being two cycles in the “safra zero” system. The design used was in randomized blocks (RBD) with three repetitions and 20 treatments (18 progenies and two commercial cultivars) totaling 60 experimental plots. We evaluated the area under the progress curve of incidence and severity of leaf rust and cercosporiosis, the productivity (sacs ha-1), sieve #16 and over (%), mocha-type grains (%) and apparent specific mass of grains (tonm-3). The genotype 12 (H516-2-1-1-18-1-4) was responsive to the framework pruning and kept its productivity stable in both pruning cycles, being efficient in such system of crop conduction, besides presenting low incidence and severity of coffee leaf rust and cercosporiosis and high sieve.
  • Imagem de Miniatura
    Item
    Estimation of genetic parameters and selection of Coffea canephora progenies evaluated in Brazilian Western Amazon
    (Editora UFLA, 2020) Bergo, Celso Luis; Miqueloni, Daniela Popim; Lunz, Aureny Maria Pereira; Assis, Giselle Mariano Lessa de
    Coffee has emerged as an economic alternative culture in the State of Acre, Brazil, but without a clonal variety recommended for the state to overcome the unevenness presented by seed crops. Thus, in order to estimate genetic parameters and indicate progenies of Coffea canephora to compose a clonal variety for the State of Acre, yield, vegetative vigor and plant height were evaluated in five harvests of a randomized complete block experiment with 46 progenies, 4 repetitions and 10 plants per plot by mixed model methodology (REML/BLUP). The harvests were evaluated individually, by the model that considers one harvest, one location and the mean of progenies, and joint analysis (all harvests), by repeatability model with stability and temporal adaptability by the harmonic mean of relative performance of genotypic values method (MHPRVG), with genotypic values of progenies grouped by the Tocher method. There was variability, with possibility of selection, only for grain yield. The yield was strongly affected by production bienniality, with high environmental influence and harvests mean ranging from 14.13±4.60 to 46.20±14.94 bags ha-1 and individual heritabilities from 0.10 to 0.44. Sixteen‘Conilon’ coffee progenies with selection gains above 23% were selected. The MHPRVG method allows the refinement of progeny selection throughout the harvests, identifying the most adapted and stable.