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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
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/16769 |
| Date | 27 February 2009 |
| Creators | Alves, Milena Ferreira |
| Contributors | CPF:69250618620, http://lattes.cnpq.br/2493954146850909, Freire, Eleusio Curvelo, CPF:02316153453, http://lattes.cnpq.br/2400072395820099, N?brega, M?rcia Barreto de Medeiros, CPF:41943554404, Hoffmann, L?cia Vieira, Barroso, Paulo Augusto Vianna |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Gen?tica e Biologia Molecular, UFRN, BR, Gen?tica e Biologia Molecular |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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