Doutorado em Genética e Melhoramento de Plantas (EA)
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Navegando Doutorado em Genética e Melhoramento de Plantas (EA) por Assunto "Barbatimão"
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Item Diversificação e radiação recente de Stryphnodendron adstringens (Leguminosae) no cerrado: consequências genéticas frente às mudanças climáticas(Universidade Federal de Goiás, 2019-09-27) Braga, Ramilla dos Santos; Telles, Mariana Pires de Campos; http://lattes.cnpq.br/4648436798023532; Telles, Mariana Pires de Campos; Jardim, Tatianne Piza Ferrari Abreu; Chaves, Lázaro José; Lima, Jacqueline de Souza; Pinto, Rafael BarbosaThe species Stryphnodendron adstringens (barbatimão) is considered a valuable genetic resource of the Brazilian Cerrado, mainly due to its medicinal properties. It has been exploited in an extractive manner in its natural habitat, requiring studies of conservation and management plans. Species of this genus had recent diversification in the Cerrado, becoming interesting models for evaluating intraspecific genetic patterns in the biome. In this context, the objective of this work was to evaluate the phylogeographic patterns of S. adstringens, in order to infer about the hypotheses of diversification of their lineages in time and space. Beyond to measure the impact of future climate changes on the geographic distribution of the genetic variation of this species. For this, the DNA polymorphism of chloroplastid (psbA-trnH and trnL-F) and nuclear (ETS) regions was quantified in individuals from 17 localities in the Cerrado. Haplotype and nucleotide diversity levels were evaluated to verify the population genetic differentiation. Coalescence analyses were performed to estimate historical demographic parameters and to identify divergence time among populations of S. adstringens. The environmental suitability of S. adstringens in the past, present and historical refuge was used to identify spatial patterns on population genetic diversity. Current and future genetic clusters were simulated from climatic scenarios. Low genetic diversity was found for cpDNA and ETS and the geographical distribution of haplotypes reflects an incomplete lineage sort. There are discordant patterns of interpopulation genetic differentiation between regions of the genome, with greater effect for cpDNA. Historical demographic equilibrium was evidenced for S. adstringens, contrary by ENM, indicating retraction of range. Most recent common ancestor was dated to 1.7 Ma ago, dividing into two main clades with most of the diversification events dating to the Middle Pleistocene. The spatial structure is stronger for ETS, suggesting the existence of isolation by distance and environmental isolation due to temperature variations. Populations closer to the edge of the historic refuge have greater genetic diversity that can be associated with multiple historical refuges and ecological transition from forest to savanna environments. Genetic clusters modeled under current and future climatic conditions, indicate losses and homogenization of genetic variation for the species. The data corroborate the recent population diversification of S. adstringens in the Cerrado, reinforcing the phylogenetic pattern in species of this genus. Beyond, low levels of genetic diversity, reflecting the effects of glacial and interglacial periods in the Pleistocene, suggesting multiple refuges formation. The impact of climate change and the disorderly exploitation of the natural populations of this genetic resource indicate the need for management and conservation plans of the species.Item Variabilidade genética e conservação de Stryphnodendron adstringens (leguminosae)(Universidade Federal de Goiás, 2020-03-23) Gonçalves, Ariany Rosa; Telles, Mariana Pires de Campos; http://lattes.cnpq.br/4648436798023532; Telles, Mariana Pires de Campos; Chaves, Lázaro José; Soares, Thannya Nascimento; Pinto, Rafael Barbosa; Franceschinelli, Edivani VillaronBarbatimão (Stryphnodendron adstringens) is a Cerrado’s native tree that has multiple uses, especially medicinal. In view of its ethnobotanical and socioeconomic importance, it is pertinent that this genetic resource be characterized, in order to outline more effective strategies for its use and conservation. In this context, this work had the general objective of evaluating the magnitude and distribution of genetic variability among subpopulations of S. adstringens, aiming at the conservation of the species. The presence of genetic clusters and levels of genetic differentiation and gene flow were evaluated in order to test the hypothesis of isolation by distance (IBD). In addition, the influence of climatic components on the distribution of the genetic variability of barbatimão in future scenarios was tested. For this, nine microsatellite loci were genotyped with 605 individuals from 19 local populations in the Cerrado. Based on the results, it was found that barbatimão has a moderate genetic diversity ( e = 0.594) and a high genetic structure among the subpopulations ( ST = 0.165; p < 0.01), with low levels of inbreeding in most of the subpopulations ( IS = 0.029, p > 0.05). Clonality was detected in ten subpopulations, most frequently in the TERGO subpopulation, characterizing the mixed reproductive system of the species. It was found that geographic distance has a significant influence on the genetic differentiation of subpopulations, as in a model of isolation by distance (rm = 0.569, p < 0.01). Temperature, precipitation and altitude are components that influence the distribution of genetic variability, and consequent structuring, in S. adstringens (R²aju = 0.081, p <0.001). In addition, the simulations warned of changes in the composition of genetic groups in the face of climate change in the future. A genetic discontinuity was identified in the Araguaia River region, possibly isolating CHGMT from other subpopulations, which was corroborated by Bayesian analyses. Low gene flow rates were detected, with a reduction in the connection between subpopulations in the recent context, which were not able to neutralize the effects of genetic drift. There was evidence of a recent bottleneck in four subpopulations, which showed lower levels of genetic diversity. Based on the degree of irreplaceable, six priority subpopulations were indicated for the conservation in situ of barbatimão, or for the collection of seeds as a way to complement the ex situ conservation of S. adstringens genetic resources and guarantee the long-term genetic variability of the species.Item Caracterização parcial e tamanho do genoma de Stryphnodendron adstringens (Leguminosae)(Universidade Federal de Goiás, 2019-01-25) Souza, Ueric José Borges de; Telles, Mariana Pires de Campos; http://lattes.cnpq.br/4648436798023532; Telles, Mariana Pires de Campos; Borba, Tereza Cristina de Oliveira; Rodrigues, Flávia Melo; Taquary, Adriana Maria Antunes; Pinto, Rafael BarbosaUsing the massively parallel sequencing data generate from two individuals of the Stryphnodendron adstringens, it was possible to structure this thesis in two chapters. The first describes the assembly and annotation of the S. adstringens chloroplast genome and their comparison between species belonging to the mimosoid clade from Caesalpinoideae-Leguminosae subfamily. The second chapter describes the estimate genome size, assembly and annotation of repetitive elements and genes in the nuclear genome of the S. adstringens. Genomic libraries were sequenced using the Illumina HiSeq 2500 platform. Approximately 10 million reads were filtered and used to assemble the chloroplast genome using a combination of de novo and reference-guided strategies. The complete chloroplast genome of S. adstringens was assembled in a single circular molecule containing 162,169 base pairs, contained 111 different genes, with 77 protein-coding genes, 30 transfer tRNA and 4 ribosomal rRNA. A total of 137 microsatellites and 42 repeats structures were identified, with the highest proportion in the LSC (Large Single Copy) region. The average nucleotide variability among the five chloroplast genomes of Mimosoid species was estimated to be 0.01771. The Ka/Ks ratio indicated positive selection for three genes analyzed, rps16, psbH and clpP. The comparison of the structural characteristics in chloroplast genome among Mimosoid species demonstrated that gene coding regions are highly conserved. The phylogenetic reconstruction based on 73 protein-coding genes indicated that the Leguminosae- Caesalpinoideae subfamily was paraphyletic. The size of the nuclear genome of S. adstringens was estimated as 1C = 0.684 pg, which corresponds to a haploid genome of 669 Mpb. The nuclear genome was made of 63.320 contigs with a total size of approximately 495 Mbp. A total of 20.124 microsatellite regions were identified in the nuclear genome, with AT/TA repeats being the most frequent (44.16%). It was possible to identify that 44.58% of the nuclear genome of S. adstringens is composed of transposable elements. The most common class were retroelements, among these, the long terminal repeats (LTR) the most abundant family. 31,636 genes and 95,811 transcripts were predicted with an average of 3.03 per gene. From the total number of predicted transcripts, 60,798 were classified functionally, according to Gene Ontology. Around 1,521 transcripts (1.58%) were similar with protein sequences involved in the tannin biosynthesis pathways. This work represents a great advance in the knowledge on the structure and organization of the nuclear and chloroplast genomes of S. adstringens. In addition, the results obtained provide genomic resources for future genetic and biotechnological investigations on the species.