Doutorado em Genética e Melhoramento de Plantas (EA)
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Navegando Doutorado em Genética e Melhoramento de Plantas (EA) por Por Orientador "Chaves, Lázaro José"
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Item Variação genética quantitativa e estrutura populacional de Hymenaea stigonocarpa (Mart. Ex Hayne) no cerrado(Universidade Federal de Goiás, 2016-05-30) Castro, Rodrigo Soares de; Telles, Mariana Pires de Campos; http://lattes.cnpq.br/4648436798023532; Diniz Filho, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351; Chaves, Lázaro José; http://lattes.cnpq.br/9990967290797379; Chaves, Lázaro José; http://lattes.cnpq.br/9990967290797379; Novaes, Evandro; Rodrigues, Flávia Melo; Moura, Nara Fernandes; Soares, Thannya NascimentoThis study aimed to analyze the quantitative genetic variation within and between natural subpopulations of Hymenaea stigonocarpa (Mart. Ex Hayne), fruit tree from the Cerrado region. Six mother trees were sampled in each of the 25 subpopulations from the states of Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais and Bahia, covering a large area of the Cerrado biome. In each tree they were collected twenty fruits, which served for evaluation of biometric data of fruits and seeds. Twenty seeds of each mother tree were sown in a nursery, with five seeds per plot in four randomized blocks, constituting a test of provenances and progenies of half sibs. Analysis of variance were performed using the hierarchical model for the characters of initial development. With the produced seedlings it was planted a germplasm collection in vivo in Escola de Agronomia of Universidade Federal de Goias.The major phenotypic variation coefficients in fruits and seeds were found in the characters number of seed (47,87%) weight of the pulp (47.74%) and fruit weight (44.06%). The analysis of variance of the physical characteristics of the fruits and seeds revealed the existence of significant variation for all characters in all levels analyzed: among subpopulations, between mother trees within subpopulations and between fruit within mother tree. Of the ten characters analyzed in six the greatest variation was found between fruit within mother tree. Significant variability was found between subpopulations and between progenies within subpopulations for most quantitative traits studied, showing a great genetic variability of the sampled material, which is important for sustainability of the species and future breeding program. The heritability estimates of traits were also high, indicating success in the selection of desirable traits in a breeding program for the species. The comparative analysis between the estimated value of the QST and FST index showed no significant difference for eight of ten characters analyzed, demonstrating that there is no evidence of the action of natural selection in the differentiation between the studied subpopulations and that the differentiation found can be explained by the action of genetic drift combined with gene flow restriction between subpopulations. The value of correlation coefficient between phenotypic and geographical matrix was 0.164 (p <0.05) by Mantel test, indicating a weak correlation between the phenotypic subpopulations means and the distances between them.Item Variabilidade genética quantitativa e estrutura populacional de Dipteryx alata Vog. do cerrado(Universidade Federal de Goiás, 2017-11-30) Mota, Elias Emanuel Silva; Soares, Thannya Nascimento; http://lattes.cnpq.br/5590256762396056; Chaves, Lázaro José; http://lattes.cnpq.br/9990967290797379; Chaves, Lázaro José; Novaes, Evandro; Soares, Thannya Nascimento; Nabout, João Carlos; Rodrigues, FabrícioThe objective of this study was to estimate genetic parameters for quantitative traits of Dipteryx alata; to infer about the influence of climatic, edaphic and geographic factors on the phenotypic divergence among subpopulations and to compare the population genetic structure of the species, based on quantitative and molecular data, to infer about the adaptive processes in the subpopulations. The germplasm collection consists of 600 plants in the field, in a randomized complete block design, with four replications and one plant per plot. Seedlings from the sowing in mid-October 2011 were transplanted to the field in March 2012. A phenotypic evaluation was also carried out in the 25 natural subpopulations, in which leaf and inflorescence data were collected from adult plants in six states of Central Brazil, sampling six plants per subpopulation. A composite sample of soil was also obtained with subsamples collected in the projection of the canopy of the plants. The evaluations of the plants from the germplasm collection, for the purposes of this study, began in March 2013, being the individual accessions characterized morphologically and agronomically. The quantitative data of the collection and the natural subpopulations were submitted to descriptive analysis, analysis of variance and correlation between the silvicultural characters. From the variance components, the genetic parameters of interest were also estimated. The comparison of the population genetic structure via microsatellite marker (FST) and quantitative data (QST) was performed based on the probability distributions of the values of the two estimates, which were generated by parametric bootstrap using 10000 resamples. There was significant variation between subpopulations and progenies within subpopulations, for most of the traits evaluated. There is genetic variability both among and within subpopulation, and its structuring is inherent to the evaluated variable. The traits, initial height, final height, initial diameter, final diameter, stem height and crown diameter showed higher heritability values, having a greater potential for genetic gain by selection and breeding. The geographic distances matrix showed low magnitude correlation only with the distances matrix of the phenotypic data of leaves and with the data matrix of the nutritional contents of leaves. The results of the Mantel tests suggested that the environmental factors (climate and soil), as well as the geographical distribution of the subpopulations are associated, even in small magnitude, with the phenotypic divergence among the subpopulations. Eighteen of the twenty seven characters evaluated for the species suggest that drift is the main cause of differentiation among subpopulations.