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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11845

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Data inicial: 2000Data final: 2009Autor: search.filters.author.Cruz, Cosme DamiãoAutor: search.filters.author.Barros, Everaldo Gonçalves de

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Agora exibindo 1 - 4 de 4
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    Caracterização de linhagens endogâmicas recombinantes e mapeamento de locos de características quantitativas associados a ciclo e produtividade do feijoeiro-comum
    (Pesquisa Agropecuária Brasileira, 2003-12) Ragagnin, Vilmar Antônio; Moreira, Maurílio Alves; Cruz, Cosme Damião; Corrêa, Ronan Xavier; Barros, Everaldo Gonçalves de; Faleiro, Fábio Gelape; Schuster, Ivan
    O objetivo deste trabalho foi caracterizar 154 linhagens endogâmicas recombinantes por meio da avaliação de características quantitativas, morfológicas, moleculares e de resistência a doenças e mapear locos de características quantitativas associados a ciclo e produtividade do feijoeiro-comum. Adotando o valor do limite de detecção (LOD) de 4,0 e uma freqüência máxima de recombinação de 0,40, foram mapeados 43 marcadores em nove grupos de ligação cobrindo uma distância de recombinação total de 247,8 cM. A distância entre marcadores adjacentes variou entre 0 e 28 cM, com média de 7,3 cM. Os grupos de ligação variaram em tamanho de 2,3 a 61,2 cM. Os genes de resistência à ferrugem e à antracnose ficaram localizados no mesmo grupo de ligação. Foram mapeados locos associados às oito características quantitativas estudadas, e a explicação da variância fenotípica pelos marcadores variou de 14,03% a 40,14%. Os resultados encontrados lançam bases para o desenvolvimento de mapas específicos saturados e de utilidade em programas de melhoramento do feijoeiro-comum.
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    Simulation of population size and genome saturation level for genetic mapping of recombinant inbred lines (RILs)
    (Genetics and Molecular Biology, 2007) Silva, Luciano da Costa e; Cruz, Cosme Damião; Moreira, Maurilio Alves; Barros, Everaldo Gonçalves de
    Various population sizes and number of markers have been used to obtain genetic maps. However, the precise number of individuals and markers needed for obtaining reliable maps is not known. We used data simulation to determine the influence of population size, the effect of the degree of marker saturation of the genome, and the number of individuals required for mapping of recombinant inbred lines (RILs). Three genomes with 11 linkage groups were generated with saturation levels of 5, 10 and 20 cM. For each saturation level populations were generated with 50, 100, 154, 200, 300, 500 and 800 individuals with 100 replications for each population size. A total of 2100 populations was generated and mapped. Small marker numbers and small population sizes produced maps with more than 11 linkage groups. As population size and marker saturation increased, marker inversion and non-linked markers decreased, moreover, between-marker distance estimates were improved. In this study, a minimum size of 200, 300 and 500 individuals were necessary for obtaining reliable maps when they were evaluated over the saturation levels of 5, 10 and 20 cM, respectively.
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    Genetic distance and its association with heterosis in cacao
    (Brazilian Archives of Biology and Technology, 2003-06) Cruz, Cosme Damião; Dias, Luiz Antônio dos Santos; Marita, Jane; Barros, Everaldo Gonçalves de; Salomão, Tânia Maria Fernandes
    The efficiency of cacao breeding program can be increased by choosing superior crosses to be made between divergent clones. We assessed the genetic distance among five clones with RAPD data (genetic distance - GD) and with yield component data (Mahalanobis distance - MD). The clones were evaluated in a diallel, during five years, for five yield components. A total of 130 RAPD bands were scored. GD and MD were used to determine the correlation between genetic distances among clones and the performance of their hybrids. The correlation between GD and MD was 0.67 (P=0.03). Both distances were related to heterotic performance of hybrids for wet seed weight/plant and wet seed weight/fruit. The average hybrid performance for the same two yield components was correlated with only MD. Hence, genetic distances measured by RAPD and yield components can be used as a guide to the choice of the superior crosses.
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    Inheritance of isoflavone contents in soybean seeds
    (Euphytica, 2006-08-01) Chiari, Lucimara; Naoe, Lucas Koshy; Piovesan, Newton Deniz; José, Inês Chamel; Cruz, Cosme Damião; Moreira, Maurilio Alves; Barros, Everaldo Gonçalves de
    We studied the genetic basis of isoflavone content inheritance in soybean seeds. The progenitors BARC-8 (low isoflavone content), IAC-100 (high isoflavone content), the F1 and F2 populations derived from reciprocal crosses, and backcross populations were analyzed for isoflavone content and composition. Six isoflavones were detected: daidzin (DZ), genistin (GT), glycitin (GC), malonyldaidzin (MDZ), malonylgenistin (MGT) and malonylglycitin (MGC). DZ, GT, MDZ and MGT contents were influenced by the cytoplasm and the nuclear genes of the maternal parent. For this reason, a genetic model was considered that included the cytoplasmic effect and epistasis between nuclear and cytoplasmic genes. Except for GT, the additive effect was the most important one. For GT content the cytoplasmic effect was the most important. Except for MDZ, the epistatic effects were significant for all the isoflavone forms. Our data indicate that genetic improvement for these traits should explore the additive genetic variances in superior lines or the cytoplasmic effect and the epistatic interactions between cytoplasmic and nuclear genes to obtain the largest selection gains.