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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An?lise da estrutura gen?tica populacional da pira?na (cephalopholis fulva: serranidae) ao longo da costa e ilhas oce?nicas brasileiras

Souza, Allyson Santos de 26 April 2011 (has links)
Made available in DSpace on 2015-03-03T14:00:59Z (GMT). No. of bitstreams: 1 AllysonSS_DISSERT.pdf: 3119890 bytes, checksum: 5de05e8e42f3274421226e677a37e4ea (MD5) Previous issue date: 2011-04-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Brazil has about 8,500 km of coastline and on this scale, fishing is a historically important source of animal protein for human consumption. The national fishing background shows a growth of marine fishery production until 1985 and within this period it was recorded a steady decline. From the year 2003 fishing statistics aim to some "recovery" of the total fisheries production, which probably is related to a change in industry practice. The target of commercial fishing became smaller species with low commercial value, but very abundants. The coney, Cephalopholis fulva (Serranidae), is one of these species that have been suffering a greater fishing pressure in recent years. In order to provide data about the current situation of the genetic diversity of these populations, several molecular markers have been being used for this purpose. The prior knowledge of genetic variability is crucial for management and biodiversity conservation. To this end, the control region sequences (dloop) of mtDNA from Cephalopholis fulva (Serranidae) from five geographical points of the coast of Brazil (Cear?, Rio Grande do Norte, Bahia and Esp?rito Santo) and the Archipelago of Fernando de Noronha (FN) were sequenced and their genetic diversity analyzed. The FST values were very low (0.0246 to 0.000), indicating high gene flow between the sampled spots. The indices h and indicate a secondary contact between previously allopatric lineages differentiated or large and stable populations with long evolutionary history. Tests of Tajima and Fu showed expansion for all populations. In contrast, the mismatch distribution and SSD indicated expansion just for coastal populations. Unlike other species of the Atlantic which have been deeply affected by events on later Pleistocene, the population-genetic patterns of C. fulva may be related to recent events occurred approximately 130,000 years ago. Moreover, the data presented by geographical samples of the specie C. fulva showed high genetic diversity, also indicating the absence of deleterious effects of over-exploitation on this specie, as well as evidence of complete panmixia between all sampled populations / Brasil possui cerca de 8.500 km de litoral e diante desta dimens?o, a pesca historicamente constitui uma importante fonte de prote?na animal para consumo humano. O hist?rico nacional na pesca mostra um crescimento da produ??o pesqueira marinha at? 1985 e a partir deste per?odo registrou-se um cont?nuo decr?scimo. A partir do ano de 2003 as estat?sticas pesqueiras apontam para certa ?recupera??o? da produ??o pesqueira total, o que provavelmente esta relacionada a uma mudan?a nas pr?ticas do setor. O alvo da pesca comercial passou a ser esp?cies menores e de baixo valor comercial, por?m muito abundantes. A pira?na, Cephalopholis fulva (Serranidae) ? uma destas esp?cies alvo que vem sofrendo uma maior press?o pesqueira nos ?ltimos anos. A fim de fornecer dados sobre a real situa??o da diversidade gen?tica destas popula??es, diversos marcadores moleculares v?m sendo utilizados para esta finalidade. O pr?vio conhecimento da variabilidade gen?tica ? crucial para o manejo e conserva??o da biodiversidade. Neste intuito, sequ?ncias da regi?o controle (d-loop) do DNAmt de Cephalopholis fulva (Serranidae) de cinco pontos geogr?ficos da costa brasileira (Cear?, Rio Grande do Norte, Bahia e Esp?rito Santo) e o Arquip?lago de Fernando de Noronha (FN) foram sequenciadas e sua diversidade gen?tica analisada. Os valores de FST se revelaram muito baixos (0.0246 a 0.000), indicando intenso fluxo g?nico entre os pontos amostrados. Os ?ndices h e indicam um contato secund?rio entre linhagens alop?tricas previamente diferenciadas ou a grandes e est?veis popula??es com longa hist?ria evolutiva; Os testes de Fu e Tajima indicaram expans?o para todas as popula??es. J? as diferen?as par-a-par e o SSD indicaram expans?o apenas para as popula??es costeiras. Diferentemente de outras esp?cies do Atl?ntico que foram profundamente afetadas por eventos Pleistoc?nicos mais tardios, os padr?es gen?tico-populacionais presentes em C. fulva parecem estar relacionados a eventos mais recentes ocorridos a cerca de 130.000 anos. Al?m disso, os dados apresentados pelas amostras geogr?ficas da esp?cie C. fulva demonstram elevada diversidade gen?tica, indicando ainda a aus?ncia de efeitos delet?rios da sobrepesca da esp?cie, bem como evid?ncias de panmixia plena tanto entre as ?reas continentais, como entre estas e o regi?es insulares

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