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 Alcides Carvalho and the selection of Catuaí cultivar: interpreting the past and drawing lessons for the future(Crop Breeding and Applied Biotechnology, 2018) Andrade, Vinícius Teixeira; Guerreiro Filho, Oliveiro; Ramalho, Magno Antônio PattoThe coffee cultivar Catuaí is among the most successful cultivars in Brazilian agriculture; it has been on the market for more than 40 years. It was obtained by Dr. Alcides Carvalho, a researcher of the Instituto Agronômico de Campinas (IAC), from the cross between ‘Caturra’ and ‘Mundo Novo’ carried out in 1949 for the purpose of joining plant vigor with small plant size. Our aim was to report the activities that culminated in the recommendation of 16 lines of ‘Catuaí’, consisting of eight lines with red fruit and eight with yellow fruit, analyzing the data of several experiments. The decision regarding what to recommend was made in the F1:2 generation, based on two harvests. It became clear that Dr. Alcides should be taken as an example by all breeders, above all in his persistence, scientific rigor, and belief that farmers can be an important ally of breeders.Item Resistance to bacterial halo blight in Arabica coffee lines derivative from the genotype C1195-5-6-2 under natural infection conditions(Crop Breeding and Applied Biotechnology, 2018) Andreazi, Elder; Sera, Gustavo Hiroshi; Sera, Tumoru; Fonseca, Inês Cristina de Batista; Shigueoka, Luciana Harumi; Santos, Willian Gabriel dos; Pereira, Carlos Theodoro MottaThe aim of this study was to identify resistance to bacterial halo blight in Arabica coffee lines carrying Coffea racemosa genes. Eighteen Arabica coffee lines derivative from the genotype C1195-5-6-2, and the cultivars IAPAR 59 and IPR 99 were evaluated for resistance to bacterial halo blight in two trials carried out in field conditions, in Londrina, PR, Brazil. The cultivars Mundo Novo IAC 376-4 and Catuaí Vermelho IAC 81 were included as susceptible controls. Ten lines and the cultivar IAPAR 59 showed resistance to bacterial halo blight. The cultivar IPR 99 presented intermediate reaction, and the controls were very susceptible. This is the first study to show that lines derivative from the genotype C1195-5-6-2, which has C. racemosa genes, could be a source of resistance to bacterial halo blight in coffee breeding programs.Item Prediction of genetic gains from selection in Arabica coffee progenies(Crop Breeding and Applied Biotechnology, 2011-09-08) Oliveira, Antonio Carlos Baião de; Pereira, Antonio Alves; Silva, Felipe Lopes da; Rezende, Juliana Costa de; Botelho, César Elias; Carvalho, Gladyston RodriguesGains from selection for yield were estimated in Arabica coffee progenies carrying rust-resistance genes. The experiment in augmented block design was installed in Três Pontas, state of Minas Gerais. Three blocks were established with six plants per plot, spaced 3.50 x 0.90 m, in 96 regular (F2 progenies) and two control treatments. The plant response to rust was evaluated on a grade scale in 2008. Yield (bags per hectare) was estimated in the growing seasons 2005 to 2008. Significant differences between treatments for yield were observed in all harvests, except 2005. The presence of genetic variability among progenies allowed significant gain from selection for yield. Under the experimental conditions of this study, selection for yield can be performed in the first high-yield year, without major losses compared to genetic gain from selection for yield when based on the mean of four harvests.Item Coffea arabica clones resistant to coffee leaf miner(Crop Breeding and Applied Biotechnology, 2016-03) Guerreiro Filho, Oliveiro; Mendonça, Alex Paulo; Nonato, Juliana Vieira Almeida; Andrade, Vinícius Teixeira; Fatobene, Bárbhara Joana dos Reis; Braghini, Masako Toma; Prela-Pantano, AngelicaBrazilian arabica coffee production is based on a set of highly productive cultivars sexually propagated. All of them are susceptible to coffee leaf miner, Leucoptera coffeella, and most of them are also susceptible to coffee leaf rust, Hemileia vastatrix. Aiming to reduce the selection process of cultivars with multiple resistances to both biotic constraints, the Coffea arabica clones 760, 1059, 1064 and 1215 were evaluated under field conditions. The mean yield of four C. arabica clones was not statistically different from the experimental controls; however, the yield of clone 1059 was 21% higher than the control cultivar Obatã IAC 1669-20. Leaf miner resistance level in all the evaluated clones remained the same as the mother plant’s. However, the same did not occur for resistance to H. vastatrix, due to the emergence of new pathogen races. In summary, it is potentially feasible the adoption of clone 1059 as a new clonal cultivar resistant to coffee leaf miner.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.