Crop Breeding and Applied Biotechnology
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Item Reproducibility of the RAPD marker and its efficiency in coffee tree genotype grouping analysis(Crop Breeding and Applied Biotechnology, 2002) Sakiyama, Ney Sussumu; Teixeira-Cabral, Terezinha Aparecida; Zambolim, Laércio; Pereira, Antonio Alves; Barros, Everaldo Gonçalves; Sakiyama, Cássia Camargo HargerThe genetic diversity of Coffea arabic L. cultivars is relatively narrow and its assessment and increase is important for breeding. Fifty two arbitrary primers were used to evaluate the reproducibility and the influence of the number of RAPD (Random Amplified Polymorphic DNA) markers on the estimation of genetic distances among 40 genotypes of Coffea spp. The average number of polymorphic bands was 6.69 per primer among all genotypes, and 1.27 among arabica coffee genotypes. RAPD markers were efficient in estimating the genetic distances among the genotypes. The increase in RAPD loci number during grouping analysis did not affect the major groups’ composition; however, it affected the composition of subgroups. Marker reproducibility was 76.88% and replicated data was recommended for distinguishing genotypes with the same genetic background.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 Comparison of nutritional efficiency among hydroponic grafted young coffee trees for N, P, and K(Crop Breeding and Applied Biotechnology, 2004) Tomaz, Marcelo Antonio; Sakiyama, Ney Sussumu; Martinez, Hermínia Emília Prieto; Cruz, Cosme Damião; Zambolim, Laércio; Pereira, Antonio AlvesGrafted Coffea arabica L. plants were grown hydroponically in a greenhouse for an evaluation of their nutritional efficiency under the influence of different rootstocks. Four C. arabica genotypes were used as scions: ‘Catuaí Vermelho IAC 15’, ‘Oeiras MG 6851’, and lines H 419-10-3-1-5, and H 514-5-5-3. The three latter are cultivars resistant to the Hemileia vastatrix, pathogen of the orange rust. Rootstocks were three genotypes of Coffea canephora Pierre et Froenher: Apoatã LC 2258, Conilon, and Robustão Capixaba (Emcapa 8141), and one C. arabica genotype: Mundo Novo IAC 376-4. Rootstocks Apoatã LC 2258 and Mundo Novo IAC 376-4 were outstanding. Cultivars Conilon and Robustão Capixaba did not increase the nutritional efficiency of the scions. ‘Oeiras’ and H 419-10-3-1-5 had considerable nutrition efficiency when used as nongrafted plants.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.