Crop Breeding and Applied Biotechnology
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12091
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Resultados da Pesquisa
Item Selection for frost resistance in Coffea arabica progenies carrying C. liberica var. dewevrei genes(Crop Breeding and Applied Biotechnology, 2005) Petek, Marcos Rafael; Sera, Tumoru; Alteia, Marcos ZorzenonThis research was carried out to estimate the variability and genetic parameters for the development of cultivars more frost resistant in Coffea arabica progenies, carrying C. liberica var. dewevrei genes. There is genetic variability for frost resistance in progenies with C. liberica var. dewevrei genes. The rust resistance, vegetative vigor and yield potential should be considered when developing cultivars adapted to frost occurrence areas. Cultivars with yield precocity such as IAPAR 59, that allows a faster recovery yield after a severe frost, minimizing the damage from the phenomenon. The use of index selection is efficient to select simultaneously progenies with greater frost adaptation, vegetative vigor, rust resistance and yield.Item Single-locus inheritance and partial linkage map of Coffea arabica L.(Crop Breeding and Applied Biotechnology, 2004) Sakiyama, Ney Sussumu; Teixeira-Cabral, Terezinha Aparecida; Zambolim, Laércio; Pereira, Antonio Alves; Schuster, IvanIn a backcross population of the allotetraploid Coffea arabica L. the loci with diploid-like segregation were predominant, although a few loci with tetrassomic inheritance or distortion of the expected segregation were also observed. A partial genetic map of Coffea arabica L. was constructed with 82 RAPD loci scored in this backcross population of 104 individuals. It covered the estimated length of 540.6 cM in eight linkage groups. The linkage group size was highly correlated with the number of markers, indicating random distribution of the markers in the groups. The average distance between two markers was 7.3 cM.Item Prediction of selection gains in Coffea canephora based on factorial scores(Crop Breeding and Applied Biotechnology, 2004) Ferreira, Adésio; Cecon, Paulo Roberto; Cruz, Cosme Damião; Ferrão, Romário Gava; Silva, Marcia Flores da; Fonseca, Aymbiré Francisco Almeida da; Ferrão, Maria Amélia GavaThe technique of factor analysis in the simultaneous selection of traits and prediction of genetic gains was evaluated in Coffea canephora var. conilon. Fourteen traits in 40 assessed genotypes were evaluated at two sites. The technique was used aiming at the structuring and simplification of the data, without information loss and with biological interpretation. The experimental design was of randomized blocks in four replications, each plot containing two useful plants. The technique was efficient for the data simplification and structuring. Moreover, the estimates of the predicted gains in the traits involved in the factors showed magnitude near the direct selection gain, attesting the suitability of the technique and its use in improvement programs of the species.Item Repeatability and number of harvests required for selection in robusta coffee(Crop Breeding and Applied Biotechnology, 2004) Fonseca, Aymbiré Francisco Almeida da; Sediyama, Tocio; Cruz, Cosme Damião; Sakiyama, Ney Sussumu; Ferrão, Romário Gava; Ferrão, Maria Amélia Gava; Bragança, Scheilla MarinaThis study aimed to estimate the repeatability coefficient of the grain yield in Coffea canephora by three methods: to quantify the precision of the measurements; to predict the real value of an individual based on n evaluations; and to determine the number of phenotypic measures required in each plant to obtain an adequate precision level for an efficient discrimination of the genotypes. The coefficients of repeatability and determination were estimated based on four harvests of 80 genotypes. Highest estimates of the repeatability coefficient were obtained by the method of the principal components derived from the matrix of covariances, which expresses the correlation between each measurement pair. The prediction precision of the real individual value ranged from 65.32 to 81.59%, and remained practically unchanged from the sixth harvest on.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 Grafted young coffee tree growth in a greenhouse(Crop Breeding and Applied Biotechnology, 2002) Sakiyama, Ney Sussumu; Tomaz, Marcelo Antonio; Martinez, Hermínia Emília Pietro; Pereira, Antonio Alves; Zambolim, Laércio; Cruz, Cosme DamiãoGrafted young coffee trees were observed in a greenhouse to study the effect of different scions and rootstocks on plant growth. Four Coffea arabica L. genotypes were used as scions: the cultivars Catuaí Vermelho IAC 15 and Oeiras MG 6851, and the progenies H 419-10-3-1-5 and H 514-5-5-3. They were also used as nongrafted control plants. Four genotypes were used as rootstocks: ‘Apoatã IAC 2258’ (C. canephora), ‘Conillon’ (C. canephora), ‘Emcapa 8141’ (C. canephora), and ‘Mundo Novo IAC 376-4’ (C. arabica). ‘Mundo Novo IAC 376-4’ and ‘Apoatã IAC 2258’ were classified as good rootstocks, while ‘Oeiras MG 6851’ and “H 419- 10-3-1-5” performed well as non-grafted plants. The diallel analysis statistical model was efficient to evaluate the general combination ability of the rootstocks and, therefore, recommended for rootstock selection procedures in breeding programs.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 Characterization of differential coffee tree hostsfor Hemileia vastatrix Berk. et Br. with RAPD markers(Crop Breeding and Applied Biotechnology, 2004-03-12) Teixeira-Cabral, Terezinha Aparecida; Sakiyama, Ney Sussumu; Zambolim, Laércio; Barros, Everaldo Gonçalves de; Silva, Dalza Gomes daEighteen clones of differential coffee tree hosts for Hemileia vastatrix Berk. et Br. were characterized with RAPD markers. The genetic distances were estimated and the genealogical origin of the clones compared to data of markerbased clusters. Thirty-five primers identified 158 polymorphic loci of RAPD markers. The cluster based on the matrix of genetic dissimilarity values was compatible with information on the genealogical origin cited in literature. Specific markers for a number of clones were identified, and a combination of 12 RAPD markers allowed the characterization of the studied clones.Item Isolation, characterization and amplification of simple sequence repeat loci in coffee(Crop Breeding and Applied Biotechnology, 2008-10-09) Cristancho, Marco-Aurelio; Gaitán, Álvaro-LeónSimple sequence repeat (microsatellite) loci in coffee were identified in clones isolated from enriched and random genomic libraries. It was shown that coffee is a plant species with low microsatellite frequency. However, the average distance between two loci, estimated at 127kb for poly (AG), is one of the shortest of all plant genomes. In contrast, the distance between two poly (AC) loci, estimated at 769kb, is one of the largest in plant genomes. Coffee (AC)n microsatellites are frequently associated with other microsatellites, mainly (AT)n motifs, while (AG)n microsatellites are not normally associated with other microsatellites and have a higher number of perfect motifs. Dinucleotide repeats (AG) and (AC) were found in ATrich regions in coffee. Sequence analysis of (AC)n microsatellites identified in coffee revealed the possible association of these repeated elements with miniature inverted-repeat transposable elements (MITEs). In addition, some of the evaluated SSR markers produced transposon-like amplification patterns in tetraploid genotypes. Of 12 SSR markers developed, nine were polymorphic in diploid genotypes while 5 were polymorphic in tetraploid genotypes, confirming a greater genetic diversity in diploid species.