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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Genotypic variability of rooting capacity in Coffea arabica L. cuttings(Crop Breeding and Applied Biotechnology, 2002) Sera, Tumoru; Fadelli, SérgioCutting propagation of coffee trees has been used for several years in Coffea canephora because of the advantages of this technique compared to seed propagation. Recently, the production of heterotic arabic coffee hybrid genotypes increased the importance of conventional and biotechnological cloning also for C. arabica. Two experiments were carried out to assess cutting rooting of several C. arabica genotypes. In greater detail, the potential of two types of cutting of several hybrid genotypes compared to C. canephora genotypes was investigated. The experiment was carried out under shading with automatic misting in boxes of partially burnt rice husks during the summer months. There is genetic variability for cutting rooting capacity among the C. arabica genotypes. The F1 hybrids tended to perform better than the lines. Single-node soft-wood cuttings were superior to the tip cuttings. Selection only for cutting rooting characteristics and useable cuttings resulted in efficient selection especially among single-node soft-wood cuttings. In spite of the large observed difference between the cutting production of C. arabica and C. canephora, in some cases C. arabica genotypes can be obtained with rooting performance very close that observed in C. canephora.Item Coffee Genetic Breeding at IAPAR(Crop Breeding and Applied Biotechnology, 2001) Sera, TumoruThis paper introduces the coffee genetic breeding research program developed by IAPAR (Agronomic Institute of Paraná, Brazil) which started in 1973. The characteristics of a breeding program for a seed-propagated perennial plant with a biennial production and the difficulties in assessing yield and longevity due to the time limitations they impose on the development and release of commercial cultivars are presented. A concise diagnosis of the arabica coffee crop in the region and the cultivar management and developmental strategies and priorities within the “IAPAR Model for dense population coffee crop” are detailed. The advances in cultivar development and management, integrated with other technologies for the solution of main problems are discussed and, an array of alternative procedures, techniques, methods and strategies to reduce the coffee cultivar development time from 24 to 12 years are proposed.Item Genetic relationship in Coffea species and parentage determination of interspecific hybrids using ISSR (Inter- Simple Sequence Repeat) markers(Sociedade Brasileira de Genética, 2003) Ruas, Paulo M.; Ruas, Claudete F.; Rampim, Leandro; Carvalho, Valdemar P.; Ruas, Eduardo A.; Sera, TumoruInter-simple sequence repeat (ISSR) markers were used to evaluate genetic divergence among eight Coffea species and to identify the parentage of six interspecific hybrids. A total of 14 primers which contained different simple sequence repeats (SSR) were used as single primers or combined in pairs and tested for PCR amplifications. Two hundred and thirty highly reproducible fragments were amplified, which were then used to estimate the genetic similarity and to cluster the Coffea species and hybrids. High levels of interspecific genetic variation were revealed. The dinucleotide motif (GA)9T combined with other di- tri- and tetra-nucleotides produced a greater number of DNA fragments, mostly polymorphics, suggesting a high frequency of the poly GA microsatellite motifs in the Coffea genomes. The genetic similarity ranged from 0.25 between C. racemosa and C. liberica var. dewevrei to 0.86 between C. arabica var. arabica and Hybrid N. 2. The C. arabica species shared most of its markers with five of the six hybrids suggesting that it is the most likely candidate as one of the progenitors of those hybrids. These results revealed that ISSR markers could be efficiently used for genetic differentiation of the Coffea species and to identify the parentage of Coffea interspecific hybrids.Item Assessment of genetic variability within and among coffee progenies and cultivars using RAPD markers(Sociedade Brasileira de Genética, 2003) Silveira, Sheila Recepute; Ruas, Paulo Maurício; Ruas, Claudete de Fátima; Sera, Tumoru; Carvalho, Valdemar de Paula; Coelho, Alexandre Siqueira GuedesThe RAPD technique associated with restriction digestion of genomic DNA was used to assess the genetic variability within and among nine populations of Coffea arabica, including six progenies belonging to the Sarchimor germplasm, the progeny PR 77054-40-10 (Catuaí Vermelho IAC 81 x Icatu), and two commercial cultivars (IAPAR 59 and Catuaí Vermelho IAC-81). These populations were evaluated using analysis of molecular variance (AMOVA), genetic similarity among progenies, and percentage of polymorphic loci. A total of 99 RAPD markers were evaluated of which 67 (67.67%) were polymorphic. AMOVA showed that 38.5% and 61.5% of the genetic variation was distributed among and within populations, respectively. The fixation index (FST) of the genotypes was 0.385. The mean genetic variability estimated within populations ranged from 15.58 (IAPAR 59) to 8.27 (Catuaí Vermelho IAC 81). A distinct level of genetic variability was revealed for each of the coffee progenies and varieties studied. The methodology used in this investigation was useful to determine the genetic variability within and among C. arabica L. populations providing significant information for coffee breeding.Item Partial resistance to fruit necrosis associated to Colletotrichum spp. among arabic coffee genotypes(Instituto de Tecnologia do Paraná - Tecpar, 2007-05) Sera, Gustavo Hiroshi; Sera, Tumoru; Ito, Dhalton Shiguer; Azevedo, José Alves de; Ribeiro Filho, Claudionor; Mata, João Siqueira daThe aim of this study was to evaluate the resistance to fruit necrosis associated to Colletotrichum spp. in Coffea arabica L.. Twenty-two arabic coffee genotypes were performed in a randomized block design, with three replications and ten plants per plot. They were evaluated for the variables fruit necrosis, luminosity index inside of the plant canopy and fruits per productive nodes of the plants. There was genetic variability for the resistance to fruit necrosis. Different partial resistance levels, varying from highly susceptible (score = 3.89) to moderately resistant (score = 1.77) were observed. The genotypes that presented moderate resistance were the cultivars IPR- 100, IPR-103, IPR-105 and IPR-108 and the coffee selection IAPAR-00023.Item Selection of Arabic coffee progenies with rust resistance(Crop Breeding and Applied Biotechnology, 2014-06) Shigueoka, Luciana Harumi; Sera, Gustavo Hiroshi; Sera, Tumoru; Fonseca, Inês Cristina de Batista; Mariucci Junior, ValdirThe aim of this study was to select high-yielding coffee progenies with resistance to coffee leaf rust for the State of Paraná (Brazil). Field experiments in a randomized block design were carried out in Itaguajé and Congonhinhas. Yield, vegetative vigor and rust resistance of nine progenies of Arabic coffee and three check cultivars were evaluated. Many genotypes derived from “Sarchi- mor” and “Catucaí” were susceptible. Three coffee genotypes of Sarchimor germplasm and the F 6 generation of genotype “Catuaí x (Catuaí x BA-10 coffee)” were selected to advance generations and are promising to become new cultivars for being higher-yielding than ‘IAPAR 59’ and ‘Tupi IAC 1669-33’ and having a large number of plants with complete rust resistance.