Submitted by (ana.araujo@ufrpe.br) on 2017-02-22T14:12:14Z No. of bitstreams: 1 Uiara Cavalcante Silva.pdf: 1481908 bytes, checksum: fd082dc957b87d6e76fa41b38fce3ac3 (MD5) / Made available in DSpace on 2017-02-22T14:12:14Z (GMT). No. of bitstreams: 1 Uiara Cavalcante Silva.pdf: 1481908 bytes, checksum: fd082dc957b87d6e76fa41b38fce3ac3 (MD5) Previous issue date: 2012-02-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / n Brazil three cotton species occur: G. barbadense, G. hirsutum and G. mustelinum, being the last wild and native of Brazil, found only in the semi-arid regions of Rio Grande do Norte and Bahia. The studied populations distribute themselves preferably near watercourses, like predominant vegetation of ciliary forest. The degradation of the environment by grazing of goats and anthropic activities, caused the reduction of these populations and consequently the variability. However, in spite of the low variability in these populations, this whole gene pool may in the future be useful in breeding programs. Therefore, the detailed knowledge of the structure of the existing variability is essential for a better use of this species as a resource of allelic variability. As commercial varieties have a narrow genetic base, due to the strong selection practiced for breeding and deriving mostly from only one species, G. hirsutum var. Latifolium, the use of new alleles is fundamental to increase allelic combinations, so that germplasm of wild species of the genus Gossypium, such as G. mustelinum, becomes an alternative for such an extension. In order to determine the variability and genetic structure of 16 natural populations of G. mustelinum, DNA extractions, PCR reactions with SSR markers were performed and the amplified alleles were used to estimate the allelic frequencies, the expected and observed heterosomy Genetic diversity analysis and Nei G statistics, as well as clustering analyzes, using the Nei and Neighbor-Joining distance. The distance between the genotypes was calculated based on the proportion of alleles using the MICROSAT program and the genotypes grouped from the UPGMA method in MEGA 4. To determine if the diversity of each of the populations was presented in an organized spatial structure, the matrix Genetic distance was compared to the physical distance matrix using the Mantel test. The results showed that the greatest diversity is found among populations, with a high level of intrapopulation inbreeding, probably due to the effects of genetic drift, evidenced by the high number of exclusive alleles. / No Brasil ocorrem três espécies de algodoeiro: G. barbadense, G. hirsutum e G. mustelinum, sendo a última silvestre e nativa do Brasil, encontrada, apenas no semi-árido dos Estados do Rio Grande do Norte e Bahia. As populações estudadas distribuem-se preferencialmente próximas de cursos de água, como vegetação predominante de mata ciliar. A degradação do ambiente por pastejo de caprinos e atividades antrópicas, provocou a redução dessas populações e consequentemente da variabilidade. Entretanto, apesar da reduzida variabilidade existente nessas populações, todo esse conjunto gênico poderá, futuramente, ser útil nos programas de melhoramento. Para tanto, o conhecimento detalhado da estruturação da variabilidade existente é essencial para melhor utilização dessa espécie como recurso de variabilidade alélica. Como as variedades comerciais apresentam base genética estreita, devido a forte seleção praticada para o melhoramento e derivarem em sua maioria de apenas uma espécie, a G. hirsutum var. latifolium, a utilização de novos alelos é fundamental para aumentar as combinações alélicas, de maneira que germoplasma de espécies silvestres do gênero Gossypium, como G. mustelinum, se torna uma alternativa para tal ampliação. Com o objetivo de determinar a variabilidade e estrutura genética de 16 populações naturais de G. mustelinum, foram feitas extrações de DNA, reações de PCR com marcadores SSR e os alelos amplificados foram empregados para estimar as frequências alélicas, a heterosigozidade esperada e observada, a análise de diversidade genética e as estatísticas G de Nei, como também, as análises de agrupamento, usando a distância de Nei e Neighbor-Joining. A distância entre os genótipos foi calculada com base na proporção de alelos usando o programa MICROSAT e os genótipos agrupados a partir do método de UPGMA no MEGA 4. Para determinar se a diversidade de cada uma das populações se apresentava numa estrutura espacial organizada, a matriz de distância genética foi comparada com a matriz de distância física usando o teste de Mantel. Os resultados demonstraram que a maior diversidade encontra-se entre as populações, com elevado nível de endogamia intrapopulacional, provavelmente devido aos efeitos de deriva genética, evidenciado pelo elevado número de alelos exclusivos.

To increase genetic diversity with elite upland cotton, introgression populations with wild species of cotton, Gossypium mustelinum and G. tomentosum, were created. To accomplish this objective, F1, F2, BC1F1, and BC1F2 generations were developed along with random mating populations (BC1rm1 and BC1rm2) and grown in a randomized complete block design with four replications in College Station, Texas during 2003 and 2004, and in Mexico during 2005 for G. mustelinum introgression populations. These generations were tested with microsatellite markers from chromosome 11 in order to measure the effects of selection and recombination. Later generations (BC2F1, BC2rm1, BC2F2, BC3F1, BC3rm1 and BC3F2) and composite generations were evaluated in a randomized complete block design with four replications during 2004 and 2005 for agronomic properties. Introgression barriers for G. mustelinum were found to include daylength sensitivity and hybrid breakdown, which was only apparent in Mexico. Backcross generations had improved fiber quality. Random mating populations did not have increased variance and means differed little from BC1F1 levels. Microsatellite markers showed decreased frequency of G. mustelinum alleles and decreasing heterozygosity, but no increase in map distances in random mating populations. Upper-half mean length and upper quartile length by weight were highly heritable, as measured with parent-offspring regression. Most other agronomic traits had moderate heritabilities. Composite generations were found to be favorable for selection and breeding. For G. tomentosum populations, hybrid breakdown was also a problem with low yields for F2 and BC1F2 generations, but day length sensitivity was not. Little or no increase in variance was found in random mating populations when compared to BC1F1 levels. G. tomentosum populations did not show improvements in fiber length as seen in G. mustelinum populations, but did have increased strength in BC1F1 and F1 generations over TM-1. Mapping distances increased in the random mating populations for G. tomentosum, and the frequency of alien alleles did not decrease in random mating populations. Generation means approached recurrent parental values for most traits within three backcrosses. Composite generations were found to be the most useful for breeding and selection.

Made available in DSpace on 2014-12-17T15:18:11Z (GMT). No. of bitstreams: 1 MilenaFA.pdf: 1164866 bytes, checksum: 847b20831744976f00087ef23a650106 (MD5) Previous issue date: 2009-02-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Gossypium mustelinum Miers ex Watt is the only cotton species native from Brazil. It is endemic of the semi-arid region from North-east of the country, where it occur near from resilient water sources. The threats to the in situ conservation of the populations are caused by human interference in its habitat, mainly by excessive cattle graze and deforestation. Establish efficient strategies of in situ conservation depend on the accomplishment of a diagnosis of how the specie is found in its natural environment, and the knowledge about the genetic structure of the populations. The objectives of this work were i) to determine the in situ conditions of two populations present in rivers from basin of Rio Paragua?u at the Bahia State, ii) to evaluate the structure and genetic variability presented in both populations, iii) to establish in situ and ex situ conservation strategies. It were realized collection in november 2007, when was realized in situ characterization of G. mustelinum. SSR markers were used for analyze 218 genotypes deriving from two populations of the G. mustelinum, localized at Toc? river and the Capivara river. The allelic frequencies, the heterozigosity and the F statics were estimated. All the plants were classified as wild and natives, and there was no evidence of the use the plants or its parts. The populations showed different conservation conditions in situ. Few plantlets were found in sites with excessive cattle feed, an indication that the damages in young plants should be high enough to compromise the renovation of the populations. On the other hand, populations were well preserved when the anthropic damages was low or inexistent. The 14 SSR primer pairs amplified 17 loci with a medium number of 5 alleles per locus (a total of 85 alleles). The high level of endogamy estimated (FIS=0,808) and the low observed heterozygosity (H0=0,093) were indicatives that the populations reproduce mainly by selfing, geitonogamy and crosses between related individuals. The genetic diversity was high (HE=0,482) and the differentiation between the populations was very high (FST=0,328). At least two sites from both populations of G. mustelinum must be preserved to achieve suitable in situ conservation. Actions that preserve the gallery forest and keep the cattle away should implemented, and could be as simple as erecting a fence. It is not possible anticipated if the in situ preservation will be possible. Therefore collections and ex situ preservation of representative specimens are essential to conserve the genetic diversity of native G. mustelinum / Gossypium mustelinum Miers ex Watt ? a ?nica esp?cie de algod?o nativa do Brasil. ? uma esp?cie end?mica do semi-?rido nordestino do pa?s, ocorrendo pr?ximo a fontes de ?gua mais duradouras. Os riscos para conserva??o in situ das popula??es est?o associados a interfer?ncia humana em seu habitat, principalmente devido ao excessivo pastejo por bovinos e caprinos, al?m do desmatamento em matas ciliares. Estabelecer estrat?gias eficazes de conserva??o in situ depende da realiza??o de um diagn?stico da esp?cie em seu ambiente natural, e do conhecimento acerca da estrutura gen?tica das popula??es. Os objetivos deste trabalho foram: i) determinar as condi??es in situ de duas popula??es presentes em rios da bacia do Rio Paragua?u no estado da Bahia, ii) avaliar a estrutura e variabilidade gen?tica presente em ambas as popula??es, iii) e estabelecer estrat?gias de conserva??o in situ e ex situ. Foram realizadas coletas em novembro de 2007, quando foi realizada a caracteriza??o in situ de G. mustelinum. Marcadores SSR foram usados para analisar 218 gen?tipos de duas popula??es, localizadas nos rios Toc? e Capivara. As freq??ncias al?licas, a heterozigozidade e as estat?sticas F foram estimadas. Todas as plantas foram classificadas como selvagens e nativas, e nenhuma evidencia de explora??o antr?pica foi observada. As popula??es apresentavam diferentes condi??es de conserva??o in situ. Poucas plantas foram encontradas em locais onde havia pr?tica de pecu?ria extensiva, um ind?cio de que os danos causados a plantas jovens sejam maiores, comprometendo a renova??o das popula??es. Em contraste, popula??es foram encontradas em adequadas condi??es de preserva??o quando os danos causados pela a??o antr?pica eram pequenos ou inexistentes. Os 14 pares de primers SSR amplificaram 17 locos com n?mero m?dio de 5 alelos por loco (85 alelos no total). O alto ?ndice de endogamia estimado (FIS=0,808) e a baixa quantidade de heterozigotos (Ho=0,093) indicam que as popula??es propagam-se preferencialmente por autofecunda??o, geitonogamia e cruzamentos entre indiv?duos aparentados. A diversidade gen?tica total foi alta (HE=0,482) e a diferencia??o entre as popula??es foi muito elevada (FST=0,328). No m?nimo duas sub-popula??es devem ser preservadas em cada rio para uma adequada conserva??o in situ. A??es de preserva??o das matas ciliares e que impe?am o acesso do gado ?s popula??es devem ser implementadas, erguendo cercas pr?ximas as plantas. N?o ? poss?vel prever se as sugest?es propostas para preserva??o in situ ser?o implementadas. Coletas devem ser intensificadas e a??es para preserva??o ex situ devem ser realizadas para conserva??o da diversidade gen?tica presente nesta esp?cie nativa do Brasil