oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 1 )

2019 ( 11 )

2018 ( 31 )

2017 ( 16 )

Custom range...

Search Results: 1 - 10 of 10828 matches for " Uilson Vanderlei Lopes "
All listed articles are free for downloading (OA Articles)
Page 1 /10828
Display every page Item
Characterization of the Sexual Self- and Cross-Compatibility in Genotypes of Cacao  [PDF]
Samuel Martins de Jesus Branco, Daniela Viana da Silva, Uilson Vanderlei Lopes, Ronan Xavier Corrêa
American Journal of Plant Sciences (AJPS) , 2018, DOI: 10.4236/ajps.2018.99131
Abstract: Cacao is a tree crop of high economic importance and the subject of several studies aiming the genetic improvement of the species with the incorporation of characteristics that are agronomically important to create superior genotypes. In this context, this study aimed to characterize 22 genotypes of cacao for sexual compatibility, which is a trait that is strongly associated with yield. Additionally, we identify genotypes incompatible with clone TSH-1188 through controlled intercrosses, due to the great importance of this clone in cocoa breeding. Fifteen genotypes were characterized as self-incompatible and other seven as self-compatible, considering the retention index (20%) of self-pollinated flowers. Nine genotypes were characterized for the first time: CCN-16, COCA-3310, COCA-3370/5, EB-1017, IMC-119, IMC-97, LCTEEN-37A, NA-45, and UF-612. Cacao genotypes showed flower retention index ranging from 0.0% to 55.1% after 15 days of self-pollinations. The number of retained flowers varied after self-pollination of cacao genotypes at 1, 5 and 15 days after pollination. CCN-51, Catongo, CCN-10 and P-4B, were the genotypes with minor losses of flowers after 15 days of pollination, while IMC-119 and TSH-516 had 100% of loss of flowers between 1 and 5 days after pollination. Moreover, the flower retention index 15 days after cross-pollination with TSH-1188 ranged from 0.0% to 87.5% among the tested genotypes. The results of cross-pollinations identified two genotypes that are incompatibles, EB-1017 and IMC-119. This result is important for future allelic studies of incompatibility in cacao, because it might indicate that these genotypes share the same self-incompatibility allele(s). We conclude, therefore, that this study enable the characterization of this working collection of cocoa germplasm for sexual compatibility and this information is important for subsequent crosses between cacao genotypes.
Cacao breeding in Bahia, Brazil - strategies and results
Uilson Vanderlei Lopes,Wilson Reis Monteiro,José Luis Pires,Didier Clement
Crop Breeding and Applied Biotechnology , 2011,
Abstract: Cacao was introduced in Bahia in 1756, becoming later the largest producer state in the country. In order to supportthe planting of cacao in the region, a breeding program was established by CEPEC at the beginning of the 1970s. For a long time,the program consisted in testing new hybrids (full-sibs) and releasing a mixture of the best ones to farmers. Lately, particularly afterthe witches′ broom arrival in the region, in 1989, recurrent breeding strategies were implemented, aiming mainly the developmentof clones. From 1993 to 2010, more than 500 progenies, accumulating 30 thousand trees, were developed by crossing many parentswith resistance to witches′ broom, high yield and other traits. In this period, more than 500 clones were put in trials and 39 clonesand 3 hybrids were released to farmers. In this paper the strategies and results achieved by the program are reviewed. Overall theprogram has good interface with pathology and genomic programs.
Microsatellite diversity and heterozygosity of parents of a cocoa breeding population
Milton Macoto Yamada,Fábio Gelape Faleiro,Acassi Batista Flores,Uilson Vanderlei Lopes
Crop Breeding and Applied Biotechnology , 2009,
Abstract: The purpose of this study was to determine the genetic diversity and heterozygosity of 26 clones used asparents of 27 families. The populations are being evaluated by the Comiss o Executiva do Plano da Lavoura Cacaueira(CEPLAC), in the state of BA. Nine of these clones are currently being recommended to farmers, while six others were used ascontrol. The seven microsatellite generated 52 alleles with a mean of seven alleles/locus and genetic distance ranging from0.17 to 0.90. This indicates a wide distribution of accessions and high variability. The heterozygosity ranged from 20% to86%, and more than 50% of the loci were heterozygous in 79% of the clones. Although the selection of the parents forpopulations was not based on genetic distances, the high genetic diversity and heterozygosity of parents indicate highlysegregating populations that make the selection of trees of interest possible, due to the variability.
Cacao breeding in Bahia, Brazil: strategies and results
Lopes, Uilson Vanderlei;Monteiro, Wilson Reis;Pires, José Luis;Clement, Didier;Yamada, Milton Macoto;Gramacho, Karina Peres;
Crop Breeding and Applied Biotechnology , 2011, DOI: 10.1590/S1984-70332011000500011
Abstract: cacao was introduced in bahia in 1756, becoming later the largest producer state in the country. in order to support the planting of cacao in the region, a breeding program was established by cepec at the beginning of the 1970s. for a long time, the program consisted in testing new hybrids (full-sibs) and releasing a mixture of the best ones to farmers. lately, particularly after the witches′ broom arrival in the region, in 1989, recurrent breeding strategies were implemented, aiming mainly the development of clones. from 1993 to 2010, more than 500 progenies, accumulating 30 thousand trees, were developed by crossing many parents with resistance to witches′ broom, high yield and other traits. in this period, more than 500 clones were put in trials and 39 clones and 3 hybrids were released to farmers. in this paper the strategies and results achieved by the program are reviewed. overall the program has good interface with pathology and genomic programs.
Genetic divergence in cocoa progenies for backcrossing program to witches' broom disease resistance
Yamada, Milton Macoto;Faleiro, Fábio Gelape;Lopes, Uilson Vanderlei;Flores, Acassi Batista;Pires, José Luis;Melo, Gilson Roberto Pires;
Revista Ceres , 2010, DOI: 10.1590/S0034-737X2010000100013
Abstract: backcrossing has been little used in cacao breeding, particularly due to the long time required to transfer genes and recover the genetic background of the recurrent parent. the objective of this study was to select individuals, resulting from the backcross cepec-42 x sic-19, genetically related to the recurrent parent sic-19 by using rapd molecular markers, among those with resistance to witches' broom. of the 31 plants that clustered with sic-19, 18 from the replanted material remained free of the disease in the field, with good vegetative aspect and, therefore can be used for backcross to reach the desired objective.
Marcadores microssatélites relacionados com a resistência à vassoura-de-bruxa do cacaueiro
Santos, Rogério Mercês Ferreira;Lopes, Uilson Vanderlei;Bahia, Rita de Cássia;Machado, Regina Celle Rebou?as;Ahnert, Dário;Corrêa, Ronan Xavier;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007000800010
Abstract: the objectives of this work were to evaluate cocoa tree resistance against witches'-broom, in plants originated from the crossing between tsh 1188 and ccn 51 (segregating population), by means of two methods of inoculation in field conditions, and to identify microsatellite markers specific for resistant and susceptible plants. the control plants bore identical symptoms as the plants of the segregating population in 90% of the cases under the two methods. the method of artificial inoculation in the field allows the detection of false resistance to the disease. of the 18 pairs of microsatellite primers amplified, 15 were polymorphic between genitors and six were polymorphic between the two groups of plants evaluated for resistance to witches'-broom. three previously characterized markers were confirmed as associated to qtl (quantitative trait loci) related to resistance to the witches'-broom, which is common in other populations. three new qtl for this characteristic, typical of this population, were also identified, which proves the utility of this population for cocoa breeding.
Caracteriza??o de uma popula??o de cacaueiro para mapeamento de genes de resistência à vassoura-de-bruxa e podrid?o-parda
Dantas Neto, Alfredo;Corrêa, Ronan X.;Monteiro, Wilson R.;Luz, Edna D. M. N.;Gramacho, Karina P.;Lopes, Uilson V.;
Fitopatologia Brasileira , 2005, DOI: 10.1590/S0100-41582005000400007
Abstract: cocoa (theobroma cacao) is a target for several diseases, the main one being black-pod, caused by phytophthora spp. however, witches' broom caused by crinipellis perniciosa is the most devastating cocoa disease in brazil. the search for sources of disease resistance is the first step in breeding programs. to this end, this study aimed to quantitatively characterize a progeny from the cross between the cocoa clones sic-864 and ccn-51, two contrastant genotypes for several traits, including resistance to witches' broom and black pod. the progeny was assessed under field conditions for the average number of pods per tree per year, the percentage of healthy pods, the percentage of pods with witches' broom, the percentage of pods with black pod, the average number of vegetative brooms per tree per year and the average number of cushion brooms per tree per year, for a period of four years. the descriptive statistics for productivity and resistance to diseases were computed considering the maximum, the mean and the minimum values, the standard deviation, the coefficient of variation and the distribution of frequency. the repeatability coefficient was computed to estimate the accuracy of the phenotypic measurements through the methods variance analysis, principal components and structural analysis. it was shown that this progeny segregates for resistance to witches' broom, black pod and other traits, thus illustrating its usefulness for studies of genetic mapping using molecular markers, aiming to identify genes of resistance and quantitative trait loci (qtls) different from those found in the scavina-6 clone, traditionally used in cocoa breeding programs.
Minimal Repair Redundancy for Coherent Systemin its Signatures Representation  [PDF]
Vanderlei da Costa Bueno
American Journal of Operations Research (AJOR) , 2011, DOI: 10.4236/ajor.2011.11002
Abstract: In this paper we discuss how to maintain the signature representation of a coherent system through a minimal repair redundancy. In a martingale framework we use compensator transforms to identify how the components minimal repairs affect the order statistics in the signature representation.
A Coherent System Component Importance under Its Signatures Representation  [PDF]
Vanderlei da Costa Bueno
American Journal of Operations Research (AJOR) , 2011, DOI: 10.4236/ajor.2011.13019
Abstract: In this paper we discuss how to measure the component importance for a system in its signature representation. The definition is given in terms of compensator transform and it can be considered as a new formalization of the ideas presented by Bergman [1] in the context of system signature.
Reliability Measure of a Relay Parallel System under Dependence Conditions  [PDF]
Vanderlei da Costa Bueno
American Journal of Operations Research (AJOR) , 2013, DOI: 10.4236/ajor.2013.31A009
Abstract:

In a relay system of dependent components, the failure to close reliability measure is given as a Girsanov transform of the failure to open reliability measure.

Page 1 /10828
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.