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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.
261

Comunidade de meiofauna e associações de nematoda em praias arenosas Amazônicas de macromaré: variações espaciais e sazonais

MELO, Tatianne Pereira Gomes de 27 October 2016 (has links)
Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-08-07T14:31:51Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_EstruturaComunidadeMeiofauna.pdf: 2502402 bytes, checksum: e282f91d26ec554bb9c6298d52ddb6f9 (MD5) / Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-08-08T14:15:45Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_EstruturaComunidadeMeiofauna.pdf: 2502402 bytes, checksum: e282f91d26ec554bb9c6298d52ddb6f9 (MD5) / Made available in DSpace on 2017-08-08T14:15:45Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_EstruturaComunidadeMeiofauna.pdf: 2502402 bytes, checksum: e282f91d26ec554bb9c6298d52ddb6f9 (MD5) Previous issue date: 2016-10-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Levando em consideração comunidades bentonicas, poucos estudos são direcionados à comunidade de meiofauna de regiões tropicais sob o regime de macromaré. Essa tese é dividida em dois capítulos. No capítulo 1 foram analisadas as variações espaciais e temporais na estrutura da meiofauna e das associações de Nematoda em praias com diferentes hidrodinâmicas na Ilha de Algodoal (Pará). As coletas foram realizadas ao longo de um ano (setembro/2011, dezembro/2011, março/2012 e junho/2012) em três praias da ilha: Caixa d’Agua, Farol e Princesa. A meiofauna foi composta por 14 taxons, sendo Nematoda e Tardigrada os grupos dominantes. A densidade média da meiofauna na praia da Princesa diferiu significativamente da praia do Farol sendo tal resultado atribuído a maior oferta de alimento na praia estuarina semi-exposta do Farol e a menor disponibilidade alimentar além da maior ação das ondas na praia oceânica exposta da Princesa. Todos os descritores de Nematoda (densidade, riqueza, equitatividade e diversidade) foram mais elevados na praia estuarina protegida da Caixa d’Agua e mais baixos na praia oceânica. Em relação as estações nas praias, as maiores abundâncias ocorreram na zona intermaré média e as menores na zona intermaré superior, porém a riqueza, equitatividade e diversidade apresentaram valores máximos na zona intermaré inferior. Foram identificados 131 gêneros de Nematoda. A nematofauna mostrou diferençaa significativa entre meses e estações em todas as praias. As variáveis ambientais mais bem relacionadas com os gêneros de Nematoda foram conteúdo de água, temperatura do substrato e fração de areia. No capítulo 2 foi feito um levantamento taxonômico e uma análise para identificar padrões de diversidade da meiofauna e dos Nematoda em praias arenosas de macromaré, considerando graus de morfodinâmica e latitudes: revisão literária. Até o presente momento foram identificados 46 gêneros de Nematoda nas praias dissipativas, 103 na praia dominada por maré semi-exposta; 82 na praia dominada por maré protegida; 80 na praia modificada por maré e 82 na praia ultradissipativa. Quanto as latitudes foram registradas 139 gêneros na região tropical e 107 na região temperada. / Considering benthic communities few studies are related to meiobenthic communities of tropical regions with macrotidal regime. This thesis is divided in two chapters. In chaper 1 the space temporal variations of meiofauna structure and Nematoda associations were analysed in beaches with different hydrodynamics at Algodoal Island. (Para). The samplings were made during one year (September/2011, December 2011, March/2012 and June/2012) in three beaches of the island: Caixa d’Agua, Farol and Princesa. The meiofauna was composed by 14 taxons, with Nematoda and Tardigrada as dominant groups. The mean density of meiofauna at Princesa beach was significantly different from Farol beach. The result was attributed to the higher disponibility of food in the intermediate beach (Farol) and the lower disponibility of food and higher waves action in the oceanic dissipative beach (Princesa). All Nematoda descripts (density, richness, eveness and diversity) presented higher values in the protected estuarine beach Caixa d’Agua and lower in the oceanic beach. Considering stations in the beaches, higher densities occured in the middle intertidal zone and lower values in the upper intertidal zone, however richness, eveness and diversity presented maximum values on the lower intertidal zone. 131 Nematoda genera were identified. The nematofauna was significantly different between months and stations in all beaches. Water content, subtrate temperature and proportion of sand were the enviromental variables more related to Nematoda genera. In chapter 2 was verified a taxonomic review and analysys were done to identify the diversity patterns of meiofauna and Nematoda from macrotidal sandy beaches, considering different morphodynamic states and different latitudes: a literature review. Until now 46 Nematoda genera were identified in dissipative beaches, 103 in beach dominated by semi-exposted tide, 82 in protected beach, 80 in beach modified by tide and 82 in ultradissipative beaches. Concerning latitudes, 139 genera were recorded in tropical region and 107 in temperate region.
262

Efeito isolado e combinado de Pratylenchus brachyurus e Fusarium verticillioides no desenvolvimento de dois híbridos de milho

Rosa Junior, Oelton Ferreira 26 October 2010 (has links)
This study evaluated the effect of Pratlenchus brachyurus and Fusarium verticillioides, and their relationship, on growth and development of two mayze hybrids (30F80 and 30K73). The experiment was conducted in greenhouse conditions at Pioneer Hi-bred Research Center in Itumbiara, GO, Brazil. The experimental design was randomized blocks with 15 treatments and 10 replications. Treatments included a non-inoculated control; inoculation of Fusarium in the seed and in the soil; three populations levels of Pratylenchus at sowing and at 30 days after planting (50, 100 and 500 nematodes/plot), with and without the inoculation of Fusarium in the soil; and three populations leves of Pratylenchus inoculated 30 days after sowing with Fusarium inoculated in seed at sowing. At plant maturity the following variables were evaluated: plant height and ear length, stalk diameter, root fresh and dry matter, stalk fresh and dry matter, reproduction factor and fusariosis severity on the stalk. Fusarium stalk colonization was evaluated in a scale from 1 to 9. The 30F80 hybrid had lower plant height and ear length, stalk diameter, stalk and root fresh matter when the seeds were inoculated with the suspension of Fusarium and sowing immediately after inoculation. The maize hybrids 30F80 and 30K73, showed the lowest root length, stalk fresh and dry matter, and root fresh and dry matter mainly when the soil was inoculated with Fusarium and sown in the same day, and the inoculation with 500 juveniles and/or adults of Pratylenchus, was done 30 days after sowing. The maize hybrid 30K73 obtained lower plant height and ear length when seeds were inoculated with the suspension of Fusarium and sown in the same day. Maize seeds inoculated with Fusarium verticillioides at planting decreased plant height, ear length, and root and shoot fresh weight on both hybrids. Stalk diameter of 30K73 hybrid and root length of hybrid 30K73 were also reduced. Soil inoculation of Fusarium verticillioides at planting and Pratylenchus brachyurus inoculated 30 days after planting (500 nematodes/plot) decreased root elongation and stalk, and root dry weights on both hybrids. However, plant height was only reduced on 30K73 hybrid. Future research is needed to better understand the relationship between Pratylenchus brachyurus and Fusarium verticillioides on maize growth and development. / O objetivo deste estudo foi avaliar o efeito de Pratylenchus brachyurus e/ou Fusarium verticillioides e sua relação no desenvolvimento de dois híbridos de milho (30F80 e 30K73). O experimento foi conduzido em casa de vegetação no Centro de Pesquisa da Pioneer Sementes de Itumbiara-GO. O delineamento experimental foi inteiramente ao acaso com 15 tratamentos/por híbrido (totalizando 30 tratamentos) e 10 repetições. Os tratamentos foram: testemunha (sem inoculações), inoculação de fungo nas sementes e no solo; inoculação de três populações de nematóide na semeadura e 30 dias após a semeadura (50, 100 e 500 nematóides/vaso), com e sem inoculação do fungo no solo; e três níveis populacionais de nematóides inoculados 30 dias após a semeadura, com o fungo inoculado na semente. Após a maturação (estádio R7), foram avaliadas as características: altura de planta e de espiga, diâmetro de colmo, matéria fresca e seca de raiz, matéria fresca e seca de colmo, fator de reprodução do nematóide e severidade de fusariose no colmo do milho. Observou-se que o híbrido de milho 30F80 obteve uma menor altura de planta e de espiga, diâmetro de colmo, matéria fresca de colmo e de raíz, quando as sementes foram inoculadas com a suspensão de conídios de Fusarium verticillioides e semeadura realizada no mesmo dia dessa inoculação. Os híbridos de milho 30F80 e 30K73 apresentaram o menor comprimento de raiz, matéria fresca e seca de colmo, e matéria fresca e seca de raiz, principalmente quando o solo foi inoculado com Fusarium verticillioides, semeou-se no mesmo dia e a inoculação do nematóide na população de 500 juvenis e/ou adultos de Pratylenchus brachyurus realizada 30 dias após a semeadura. O híbrido de milho 30K73 obteve uma menor altura de planta e de espiga quando as sementes foram inoculadas com a suspensão de conídios de Fusarium verticillioides e semeadura realizada no mesmo dia dessa inoculação. Sementes de milho inoculadas com o fungo na semeadura diminuiram a altura de planta e de espiga e peso fresco de raiz e de parte aérea nos dois híbridos de milho. Diâmetro de colmo no híbrido 30F80 e comprimento de raiz no híbrido 30K73 também foram reduzidos. A inoculação do solo com o fungo na semeadura e nematóide inoculado 30 dias após (500) proporcionou menor comprimento de raiz e peso seco e fresco de raiz e colmo nos dois híbridos. Contudo, altura de planta foi reduzida somente no híbrido 30K73. Outros estudos de interações entre microrganismos, em especial de Pratylenchus brachyurus e Fusarium verticilliodes, deverão ser realizados, a fim de melhor entender o efeito desta combinação no prejuízo das plantas. / Mestre em Agronomia
263

Endohelminths from six rare species of turtles (Bataguridae) from Southeast Asia confiscated by international authorities in Hong Kong, China

Murray, Rebecca Ann 30 September 2004 (has links)
Specimens of 6 species of threatened, vulnerable, and endangered turtles (Cuora amboinensis, Cyclemys dentata, Heosemys grandis, Orlitia borneensis, Pyxidea mouhotii, and Siebenrockiella crassicollis) belonging to family Bataguridae, were confiscated in Hong Kong, China on 11 December 2001 by international authorities. Endohelminth studies on these turtle species are scarce, and this study provided a rare opportunity to examine a limited number of specimens for endohelminths. Ten different parasite species were collected and there were 16 new host records. This is the first record of a parasite from P. mouhotii. The parasite prevalences found in this study provide a basis for a better understanding of the phylogenetic relationships of the family Bataguridae to other families, especially Testudinidae. Based on known life cycles, parasites found provided an indication of food preferences of these 6 turtle species that support previous studies of the turtles' feeding habits. However, the results of the parasite survey from O. borneensis provided additional feeding habit information. The list of endohelminths herein is intended to provide a foundation for future parasite studies of the 6 species of Asian turtles.
264

Endohelminths from six rare species of turtles (Bataguridae) from Southeast Asia confiscated by international authorities in Hong Kong, China

Murray, Rebecca Ann 30 September 2004 (has links)
Specimens of 6 species of threatened, vulnerable, and endangered turtles (Cuora amboinensis, Cyclemys dentata, Heosemys grandis, Orlitia borneensis, Pyxidea mouhotii, and Siebenrockiella crassicollis) belonging to family Bataguridae, were confiscated in Hong Kong, China on 11 December 2001 by international authorities. Endohelminth studies on these turtle species are scarce, and this study provided a rare opportunity to examine a limited number of specimens for endohelminths. Ten different parasite species were collected and there were 16 new host records. This is the first record of a parasite from P. mouhotii. The parasite prevalences found in this study provide a basis for a better understanding of the phylogenetic relationships of the family Bataguridae to other families, especially Testudinidae. Based on known life cycles, parasites found provided an indication of food preferences of these 6 turtle species that support previous studies of the turtles' feeding habits. However, the results of the parasite survey from O. borneensis provided additional feeding habit information. The list of endohelminths herein is intended to provide a foundation for future parasite studies of the 6 species of Asian turtles.

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