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Search Results: 1 - 10 of 306739 matches for " ?ngela de Fátima Barbosa;Ramalho "
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Sele??o recorrente fenotípica para florescimento precoce de feijoeiro 'Carioca'
Silva, Flávia Barbosa;Ramalho, Magno Antonio Patto;Abreu,ngela de Fátima Barbosa;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007001000010
Abstract: the objective of this work was to evaluate the efficiency of phenotypic recurrent selection for the number of days until blooming in common bean, and to verify if this selection affected other traits. one s0 population derived from the mixture of the f2 populations of 11 hybrid combinations evaluated for earliness was used. the plants of the s0 (cycle 0) which bloomed first were crossed to obtain cycle i. to go on with the selection the obtained seeds were used. the process was repeated until the fifth selection cycle. fifty-three s1:2 progenies of each cycle were used for evaluation of the genetic progress. the number of days to flowering, severity of angular leaf spot (phaeoisariopsis griseola), number of days to maturation, yield and grain type were evaluated. a selection gain of 2.2% per year was observed, which indicates that phenotypic recurrent selection reduced the number of days to flowering. the selection for the number of days to flowering had no correlated response with other evaluated traits, indicating that progeny selection for early flowering can be associated with the phenotypic expression of other traits, according to the breeder's interest.
Estimates of genetic parameters of late seed-coat darkening of carioca type dry beans
Araújo, Lilian Cristina Andrade de;Ramalho, Magno Antonio Patto;Abreu,ngela de Fátima Barbosa;
Ciência e Agrotecnologia , 2012, DOI: 10.1590/S1413-70542012000200003
Abstract: in order to facilitate commercialization of cultivars of carioca type dry beans, the grains must have the lightest possible cream color and this phenotype must be persistent (late seed-coat darkening). there are reports of genetic variability for this trait. the objectives of this study were to obtain information regarding genetic control of the trait, with emphasis on the estimate of heritability and if it varies according to days after harvest, to verify the effect of locations and/or crop season on seed-coat darkening of the grains and to estimate the genetic and phenotypic correlations of the trait with cooking time, tannin content and grain yield. f2:3 and f2:4 progenies derived from crossing of the cultivar brsmg madrepérola (late seed-coat darkening) and the line rp-2 (early seed-coat darkening) were used. it is concluded that seed-coat darkening is influenced by the environment, crop season or locations; nevertheless, the interaction progenies x environments and progenies x locations is predominantly simple, not expressively changing classification of the progenies. although the heritability of the darkening scores tends to increase with the storage time of the grain, the interaction progenies x time periods of assessment was not observed. grains with late seed-coat darkening present a lower tannin content and require less cooking time. the genetic correlation between a dark seed-coat and grain yield was practically null.
Controle genético da incompatibilidade do cruzamento entre cultivares andinas e mesoamericanas de feijoeiro comum
Arantes, Lúcio de Oliveira;Ramalho, Magno Antonio Patto;Abreu,ngela de Fátima Barbosa;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000300041
Abstract: crosses between andean and mesoamerican common beans are usually incompatible. there are doubts about the genetic control of the trait. singh & gutiérrez (1984) reported that two genes are involved in the trait control and that double recessive epistasis occurs. on the other hand, vilarinho (2004) presented results indicating that more than two genes are involved. the present study was carried out to clarify the genetic control of this trait. for this purpose, the andean cultivar 'jalo eep 558' was crossed with 'small white', which is mesoamerican, but compatible with the former one. the mesoamerican cultivar 'mulatinho da vagem roxa' was also crossed with 'small white'. the f1 generation of these two hybrids was crossed with each other. the resulting seeds were sown on the field and the occurrence of incompatibility was evaluated. segregation of 3 (normal) to 1 (incompatible) plants was observed, indicating that there are two genes, dl1 and dl2, as reported by singh & gutiérrez (1984), and that the genotype of the cultivars involved are: 'jalo eep 558' dl1dl1dl2dl2 ; 'mulatinho da vagem roxa' dl1dl1dl2dl2 ; 'small white' dl1dl1dl2dl2 .
Trinta e dois anos do programa de melhoramento do feijoeiro comum em Minas Gerais
Matos, José Wilacildo de;Ramalho, Magno Antonio Patto;Abreu,ngela de Fátima Barbosa;
Ciência e Agrotecnologia , 2007, DOI: 10.1590/S1413-70542007000600022
Abstract: the objective of the present work was to make critical analysis of the dry bean genetic breeding program in minas gerais in the last 32 years by lines x environments interactions and genetic progress evaluations. data from 169 experiments conducted from 1974 to 2004 in 16 locations and three seasons per year were used. the average of the cultivar carioca, test in all experiments, was used as indicator of environmental variation; and the average of the five best lines, under evaluation in each biennium, was used as indicator of phenotypic variation. the difference between these two averages was used as genetic deviation. genetic progress was estimated by linear regression coefficient between genetic deviation y (dependent variable) and biennium x (independent variable). the interactions among lines x seasons and lines x years were significant in most cases, however, their contributions to the total variation were inferior to the lines x locations. thus, it was necessary to conduct experiments in a larger number of locations. the common bean breeding program at ufla has been efficient and has selected lines with less risk for adoption for farmers.
Eight cycles of recurrent selection for resistance to angular leaf spot in common bean
Arantes, Lúcio de Oliveira;Abreu,ngela de Fátima Barbosa;Ramalho, Magno Antonio Patto;
Crop Breeding and Applied Biotechnology , 2010, DOI: 10.1590/S1984-70332010000300008
Abstract: the genetic progress (gp) was evaluated after eight cycles of recurrent selection for resistance to angular leaf spot in common bean and indirect gain for yield and grain type. the base population (cycle-0) was obtained from the diallel cross of seven lines with carioca grain and ten resistance sources. to obtain cycle i, the most resistant s0 plants of cycle 0 were intercrossed. the same procedure was adopted in the subsequent cycles. gp for resistance to the pathogen was estimated by the overall average of the progenies of each cycle in comparison with control carioca mg and for productivity in comparison to the controls carioca mg and pérola. lines of the first six cycles were used for grain type. no gp was detected for resistance to angular leaf spot. however, the indirect yield gain was 2.3% and 2.5% in the selection for grain type, with values similar to those obtained by direct selection for these traits.
Selection of common bean inbred lines with tolerance to high moisture at harvest Sele o de linhagens de feij o com tolerancia a alta umidade no momento da colheita
Lidiane Kely de Lima,Magno Antonio Patto Ramalho,ngela de Fátima Barbosa Abreu
Ciência e Agrotecnologia , 2013,
Abstract: The occurrence of precipitation / rain in harvest bean causes damage to the product and reduces the yield. The main alternative to mitigate this problem is to obtain cultivars presenting low germination of beans in the pods under conditions of high moisture. The purpose of this study was to verify if there is genetic variability among the common bean inbred lines that are in the phase of recommendation for the South of Minas Gerais, Brazil in regard to tolerance to moisture after harvest, and identify traits that may be routinely used in selection of tolerant lines to these conditions. Ninety-five lines in the phase of recommendation by the Genetic Breeding Program from UFLA were used. After harvest, a sample of plants from each plot was removed for assessments of seed germination in the pods in a moist chamber and water absorption by pod and seed. Eight days after harvest, another sample was removed to assess seed appearance using a scoring scale. The data were submitted to analysis of variance and estimates of the Pearson phenotypic correlations were obtained among traits. Lines differ in relation to tolerance to moisture at the time of harvest, with those of higher tolerance having lighter colored seeds. The main difficulty in selection of common bean lines for tolerance to high moisture at harvest is the repeatability of the environmental conditions among crop seasons. The alternative is assessing the amount of water absorbed by pods. A ocorrência de precipita o / chuva na colheita do feij o comum provoca danos ao produto e reduz o rendimento. A principal alternativa para mitigar este problema é a obten o de cultivares com baixa germina o de gr os nas vagens em condi es de alta umidade. Neste trabalho, objetivou-se vrificar se há variabilidade genética entre as linhagens do feijoeiro que est o em fase de recomenda o para o Sul de Minas Gerais quanto à tolerancia à umidade após a colheita e identificar caracteres que possam ser utilizados rotineiramente na sele o de linhagens tolerantes a essas condi es. Utilizaram-se 95 linhagens em fase de recomenda o pelo Programa de Melhoramento Genético da UFLA. Após a colheita, uma amostra de plantas de cada parcela foi retirada para avalia es de germina o dos gr os nas vagens em camara de nebuliza o e absor o de água pela vagem e pelo gr o. Oito dias após o arranquio foi retirada outra amostra para avaliar o aspecto do gr o utilizando escala de notas. Os dados foram submetidos à análise de variancia e obtidas as estimativas das correla es fenotípicas de Pearson entre os caracteres dois a dois. As
Genetic control of plant architecture in the common bean (Phaseolus vulgaris L.)
Teixeira, Flavia Fran?a;Ramalho, Magno Antonio Patto;Abreu,ngela de Fátima Barbosa;
Genetics and Molecular Biology , 1999, DOI: 10.1590/S1415-47571999000400019
Abstract: more erect plant architecture has been a goal in the development of bean cultivars. aiming to obtain more information about genetic control of traits related to plant architecture, this work was carried out between august 1995 and july 1997 in the southern and alto s?o francisco regions, in the state of minas gerais, brazil. initially, analyses were performed with individual plants of parents and different segregant generations from the crosses carioca-mg x h-4 and carioca x ft-tarum?. in these experiments, besides degree of erectness, other traits were evaluated: ramification degree, internode length, internode diameter and height of insertion of the first pod. mean and variance components and heritability at an individual level were estimated. later, families derived from f2 or f3 plants of the same crosses were evaluated for degree of erectness. genetic and phenotypic variance between family averages, heritabilities using variance components, and realized heritability were estimated. of the morphological traits, internode length varied the most. there was a predominance of additive effect in the control of this trait. evaluating plant architecture with individual plants for degree of erectness was not efficient. however, when families were used, genetic parameter estimates confirmed the possibility of successful selection, especially if evaluated for a few generations and/or environments, despite the strong environmental influence on trait expression.
Prediction of seed-yield potential of common bean populations
Abreu,ngela de Fátima Barbosa;Ramalho, Magno Antonio Patto;Santos, Jo?o Bosco dos;
Genetics and Molecular Biology , 2002, DOI: 10.1590/S1415-47572002000300013
Abstract: earliest possible prediction of seed-yield potential of autogamous crop populations increases breeding program efficiency by saving time and resources. alternatives for obtaining seed-yield predictions were compared by evaluating four common-bean populations in f1 and f2 generations together with the parents. mean components (m + a' and d) and variances were estimated. the potential of each population was predicted by using both these and the jinks and pooni (1976) procedure, which allows probability estimation of each population of originating lines surpassing a determined standard. estimate efficiency was determined by evaluating performances of 62 f5:7 families from each population. mean component m + a' estimates obtained for the f1 and f2 generations proved efficient in predicting seed yield of f7 generation lines as did d for estimate variance among f7 generation families. in addition, the jinks and pooni (1976) procedure proved efficient in early prediction of common bean population genetic potentials, especially when using the m + a' estimate.
Rea??o de linhagens de feijoeiro ao fungo Fusarium oxysporum f. sp. phaseoli em condi??es controladas
Pereira, M?nica Juliani Zavaglia;Ramalho, Magno Antonio Patto;Abreu,ngela de Fátima Barbosa;
Ciência e Agrotecnologia , 2011, DOI: 10.1590/S1413-70542011000500011
Abstract: among the pathogens that most contribute for reducing the productivity of beans in brazil is the fusarium oxysporum f. sp. phaseoli. the use of resistant cultivars is the most effective control for this pathogen. the aim of this study was to evaluate germoplasm bean (phaseolus vulgaris l.) lines of the federal university of lavras (ufla) as the reaction to the fusarium oxysporum f. sp. phaseoli and at the same time, to estimate the genetic and phenotypic parameters that could help in future programs of improvement for this character. three hundred and sixty seven lines were evaluated in ten experiments. the controls' carioca'(susceptible) and 'carioca mg'(resistant) were used in all experiments. the experimental design used was a entirely randomized one, with five replicates and plots of one plant per pot. the inoculations were carried out following the method of cutting and dumping of roots in the suspension of spores of the fungus and the assessments conducted at 21 days after inoculation based on the index of severity of the disease employing up notes of 1 (plants without symptoms) to 9 (dead plants). among the lines of germoplasm bank of the federal university of lavras (ufla) assessed, 36.5% were resistant to fusarium oxysporum f. sp. phaseoli. among the resistance, most of the lines were obtained before 1990: out of the 18 lines of the experiments of vcu evaluated in 2005/06, only four were susceptible. the estimate of heritability (h2) was high (h2 = 87%), indicating that, in principle, the character is of easy selection.
Envolvimento de agricultores no processo seletivo de novas linhagens de feijoeiro
Sena, Marcus Reis;Abreu,ngela de Fátima Barbosa;Ramalho, Magno Antonio Patto;Bruzi, Adriano Teodoro;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000200010
Abstract: this work had the objective of involving the farmers in the selection of new common bean inbred lines. ten experiments were carried out to evaluate nine inbreed lines and the commercial cultivar brsmg talism? in farm conditions of traditional common bean producers. the experimental design was a randomized complete blocks with three replications with plots of 10 rows of 5m each. angular leaf spot severity and yield were evaluated and it was required from farmers to evaluate about the grain type. inbred line op-s-30 presented the highest mean grain yield in all environments, angular leaf spot tolerance and grain type with good acceptance according to the farmers. besides the two inbred lines op-s-16 and op-s-80 presented higher performance. the results reinforced that the farmers and breeders really have very common objectives in relation to the desirable phenotypes for a common bean cultivar in the region.
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