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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.
61

Cineraria L. (Senecioneae, Asteraceae) - its taxonomy, phylogeny, phytogeography and conservation

Cron, Glynis Valerie 01 November 2006 (has links)
Student no:7719196 PhD thesis 2005 Faculty of Science, School of Animal, Plant and Environmental Sciences. / This study aimed to investigate the phylogeny of Cineraria L. to elucidate its position in the tribe Senecioneae (Asteraceae), to delimit its generic and species boundaries, explore species relationships (infrageneric structure) and produce a monograph of the genus. It also aimed to examine its distribution, phytogeographic affinities, levels of rarity and endemism in Cineraria, to identify some of the factors contributing to rarity in Cineraria and to highlight implications for conservation. Phylogenetic analyses were performed using morphological and molecular (DNA sequence) characters to elucidate relationships within the genus and between Cineraria and selected related genera in the subtribe Senecioninae. The phylogenetic species concept was applied - suites of diagnostic characters were used to characterise species. The phenetic approach, using Cluster Analysis and Principal Coordinates Analysis, was applied to investigate variation in two highly variable species, C. deltoidea Sond. and C. lobata L’Hér. Species distributions were mapped and the number of species per degree square was plotted for southern Africa to identify centres of diversity and endemism. Rare species were identified and categorised according to Rabinowitz’s criteria of geographic range, habitat specificity and local population size. Cineraria now has a more homogenous generic concept, characterised as herbs or subshrubs with palmately veined leaves, radiate, calyculate capitula, penicillate style apices and obovate, compressed cypselae with two distinct margins or wings and a substantial carpopodium. Eleven species have been removed from the genus and two new genera, Bolandia Cron and Oresbia Cron & B.Nord. have been established to accommodate three of the species. Two species have been reassigned to and another reinstated in Senecio L. The affinities of five species remain unresolved. Cineraria now comprises 35 species with four new subspecies and two new varieties recognised. Eight species have been placed in synonymy and five new species have been described during this revision. The status of C. deltoidea as a single, highly variable species, widespread throughout the eastern mountains of Africa, has been confirmed. Cineraria lobata has been shown to be a very variable species and the geographic and morphological variation has been formally (and informally) recognised. No infrageneric classification has been applied to Cineraria as a robust phylogeny of all the species has yet to be hypothesised. A southern African origin for Cineraria in the Western and/or Eastern Cape is postulated, based on the current distribution of the sister genus Bolandia and Cineraria mollis DC. iv Cineraria appears to have undergone rapid speciation fairly recently, as indicated by the lack of variation in the molecular data analysed, with reticulate evolution playing an important role in its evolutionary history (as seen by the lack of congruence between the chloroplast and nuclear DNA sequences). The centre of diversity of Cineraria is the KwaZulu-Natal Midlands, part of the Maputaland-Pondoland Centre of endemism in southern Africa. Cineraria has an afromontane affinity, and fifteen species endemic to specific mountains or regions of endemism and five near-endemics have been identified in Cineraria. Eleven species have been shown to be rare (in the sense of low abundance, restricted range and high habitat specificity), however only five are considered to be threatened as indicated by IUCN Red Data Criteria. However, at least seven species are Data Deficient and require further investigation. Causes of rarity in Cineraria are linked to narrow habitat specificity, particularly soil or rock type and/or altitudinal range.
62

Evolução e integração morfológica do crânio dos roedores da subfamília Sigmodontinae Wagner, 1843 (Rodentia, Cricetidae) / Morphological integration and evolution on Sigmodontinae rodent skulls Wagner, 1843 (Rodentia, Cricetidae)

Costa, Bárbara Maria de Andrade 19 December 2013 (has links)
A subfamília de roedores Sigmodontinae representa o clado com a maior diversidade e distribuição de mamíferos na região neotropical, sendo que a maior parte das espécies são endêmicas da América do Sul. Com inúmeras diferenças ecomorfológicas, o padrão de diversificação desses roedores, por um ponto de vista biogeográfico e filogenético, tem sido bastante debatido. Nesta tese, busco compreender a evolução dos caracteres cranianos dos sigmodontíneos, a partir do arcabouço teórico da genética quantitativa e integração morfológica. Dessa forma, tive como objetivo geral avaliar os padrões e as magnitudes de integração morfológica para compreender a associação dos caracteres e explorar suas potenciais consequências evolutivas no crânio dos Sigmodontinae. A partir de um banco de dados contendo 2897 indivíduos de 39 espécies da subfamília, testei a similaridade estrutural das matrizes de correlação e covariância ao compará-las entre todos os táxons medidos (representados por 35 medidas cranianas). Avaliei também se a história evolutiva do grupo teve influência sobre os padrões da estrutura de covariância fenotípica. Além disso, testei a presença de módulos no crânio desses roedores, a partir das hipóteses de desenvolvimento e função comum nos crânios dos mamíferos. Por fim, simulei seleção natural nesses crânios a fim de investigar as possibilidades evolutivas na associação dos caracteres cranianos nos diferentes táxons da subfamília. De uma maneira geral, os sigmodontíneos apresentaram um padrão das relações dos caracteres muito semelhante, enquanto a magnitude em que esses caracteres estão integrados variou bastante entre as espécies sendo que a amplitude dessa variação foi próxima a que já foi detectada entre outras ordens de mamíferos eutérios. Além disso, tanto os padrões quanto as magnitudes obtidas não estiveram, até um certo ponto, associadas a história evolutiva (filogenia) desses roedores. Dessa forma, observa-se que após um período de diversificação de aproximadamente 12 milhões de anos, a plasticidade na magnitude de integração acoplada ao fato que esta magnitude nunca se aproxima de 1 (portanto com algum grau de flexibilidade) pode fornecer uma explicação sobre como a grande diversidade morfológica craniana surgiu neste grupo de mamíferos, mesmo com a grande conservação nos padrões de integração. Mais ainda, os sigmodontíneos compartilham um padrão de modularidade craniana comum entre a maioria das espécies, relacionada com as hipóteses funcionais e de desenvolvimento testadas. O padrão de modularidade mostrou-se influenciado pela variação de tamanho, associado ao primeiro componente principal (CP1) de todas as espécies, assim como a magnitude geral de integração do crânio. Quanto maior a variância alométrica no CP1 maior a magnitude de associação entre os caracteres do crânio e, dessa maneira, menos modular é o crânio. Essa relação é importante para compreender o potencial da resposta evolutiva, pois, independente da direção da pressão seletiva, espécies com maior magnitude geral de integração dos caracteres são mais restritas evolutivamente, ou seja, tendem a responder à seleção na direção do eixo de maior variação (tamanho). Em contrapartida, espécies com menores magnitudes entre os caracteres cranianos são mais flexíveis a responder na direção em que seleção está atuando. Interessantemente, os sigmodontíneos apresentaram potenciais evolutivos tanto próximo dos mamíferos mais flexíveis (primatas e morcegos) quanto daqueles que possuem os maiores índices de restrição (marsupiais) / The Sigmodontinae subfamily of rodents represents the clade with the greatest diversity and distribution among mammals in the Neotropical region, with most of the species endemic to South America. With numerous ecomorphological differences, the diversification pattern of these rodents, from a phylogenetic and biogeographic point of view, has been intensely debated. In this thesis, I seek to understand the evolution of the cranial traits of the sigmodontine, using the theoretical framework of quantitative genetics and morphological integration. Thus, I aimed at evaluating the patterns and magnitudes of morphological integration, to understand the association of traits and to explore the potential evolutionary consequences of these associations for the Sigmodontinae skull. Using a collected database containing 2897 individuals of 39 species of the subfamily, I tested the structural similarity of covariance and correlation matrices by comparing them between all measured taxons (represented by 35 cranial measurements). I also evaluated if the evolutionary history of the group had an influence on the patterns of phenotypic covariance structure. Furthermore, I tested the presence of modules in these rodents skulls, employing shared developmental and functional hypothesis proposed for mammalian skulls. Finally, I simulated natural selection in these skulls in order to investigate the evolutionary possibilities in the association of cranial traits in different taxa of the subfamily. In general, the sigmodontine had very similar patterns of traits relationship, while the magnitude of trait association varied greatly among species, and the amplitude of this variation was close to what has already been detected within other Eutheria mammalian orders. In addition, both the patterns as well as the magnitudes obtained were not, to a large extent, associated with the evolutionary history (phylogeny) of these rodents. Thus, I observed that after a period of diversification of approximately 12 million years, this magnitude of integration plasticity coupled with the fact that the magnitude of association is never 1 (granting some degree of flexibility), may provide an explanation for how the wide diversity in cranial morphology appeared in this mammalian group, even with the wide conservation in the integration patterns. Moreover, the sigmodontine share a common pattern of cranial modularity among most species, which are related to the tested functional and developmental hypotheses. The modularity pattern appears to be influenced by variation in size, associated with the first principal component (PC1) of all species, as well as the overall magnitude of skull integration. The greater the variance in the allometric PC1, the greater the association between the skull traits and, thus, the skull is less modular. This relationship is important to understand the potential of the evolutionary response, seeing that, independent of the direction of selective pressure, species with higher general integration magnitude are more evolutionarily constrained, i.e, tend to respond to selection in the direction of the axis with the greatest variation (size). In contrast, species with smaller magnitudes between cranial characters are more flexible to respond in the direction in which selection is acting. Interestingly, the sigmodontine exhibited a potential to evolutionary responses that range from much flexible, both close to mammals (primates and bats ), as well as with those who have the highest levels of restriction (marsupials)
63

Padrões macroecólogicos de disparidade morfológica e distribuição de massa de mamíferos terrestres / Macroecological patterns of morphological disparity and body mass distribution in terrestrial mammals

Latorre, Daniel Varajão de 03 July 2015 (has links)
Entender a relação entre riqueza de espécies e diversidade de nichos ecológicos pode auxiliar a compreensão dos diferentes processos que governam a coexistência de espécies. Caracterizar o nicho de diversas espécies não é trivial, e o nicho é frequentemente estudado a partir de características morfológicas. A massa corpórea está relacionada com características metabólicas, fisiológicas, comportamentais e ecológicas das espécies e então é ideal para estudos ecológicos que envolvem muitas espécies e localidades. Em teoria, um aumento na riqueza de espécies poderia ocorrer tanto pela expansão do espaço de nicho total, quanto pelo empacotamento de nicho, ou mesmo por uma combinação de ambos. Neste trabalho utilizamos massa corpórea de mamíferos terrestres para investigar a ocupação do morfoespaço e a relação dessa ocupação com a riqueza de espécies tanto em assembleias locais, quanto em biotas continentais. No primeiro capítulo desta dissertação, investigamos a variação espacial da disparidade morfológica de mamíferos terrestres e sua relação com a riqueza de espécies. Utilizamos os dados de distribuição geográfica de 4146 espécies para determinar a composição de assembléias locais em um grid com células com 1º de lado. Para cada assembleia, calculamos quatro medidas de disparidade morfológica utilizando massa corpórea como um descritor da morfologia de mamíferos. Comparamos as medidas de disparidade de cada célula com o que seria esperado de acordo com dois modelos nulos (um global e outro regional) que diferem em relação ao pool utilizado para reamostragem. No segundo capítulo, investigamos o efeito da extinção da megafauna e os possíveis efeitos das extinções atuais na distribuição de massa de mamíferos terrestres. De acordo com trabalhos anteriores a distribuição de massa de mamíferos tornou-se bimodal 40 milhões de anos atrás e assim se manteve até o final do Pleistoceno, quando foi modificada pela extinção da megafauna, tornando-se unimodal. Ajustamos dois modelos concorrentes (bimodal e unimodal assimétrico) às distribuições de massa corpórea dos mamíferos de todo o globo e de cada continente separadamente em três momentos de tempo: Final do Pleistoceno, Holoceno e Antropoceno. Os resultados obtidos nos dois capítulos, apesar de observados em escalas muito distintas, sugerem um padrão de empacotamento de nichos nos Neotrópicos. Esse padrão não é influenciado pela extinção da megafauna, e se deve à diversificação de grupos específicos no continente sul americano. Grande parte das espécies dos grupos endêmicos são arborícolas sugerindo a importância das florestas tropicais na diversificação de mamíferos desse continente. Nossos resultados também sugerem que a perda das espécies ameaçadas de extinção no Antropoceno irão resultar em mudanças significativas na África e na Eurásia, dois continentes menos afetados pelas extinções do Pleistoceno / Understand the relation between species richness and ecological niche diversity might help to understand processes behind species coexistence. However, to quantify species niche is not easy and a ecomorfological approach is often used instead. Body mass is related to several life history traits such as metabolism, physiology, behaviour and ecology, thus being the ideal trait for studies comparing many different species and localities. In theory, increases in species richness could be attained by an expansion of total niche space or by niche packing, or even by a combination of both. Here we use terrestrial mammals body mass to investigate morphospace occupation and its relation to species richness in both local assemblages and continental biotas. In the first chapter, we investigate the spatial variation of morphological disparity of terrestrial mammals and its relation to species richness. We used species distributions of 4146 species to determine the composition of local assemblages in a grid of 1º cells. For each assemblage we measured four morphological disparity metrics using body mass as a surrogate of mammalian morphology. We compared the observed disparity measures for each cell with the expected distribution given by two null models (one global and other regional) that differ for the species pool used to perform resamples. In the second chapter we investigated the effect of megafauna extinctions and possible effects of ongoing extinctions on the body mass distribution of terrestrial mammals. Previous studies suggest that the body mass distribution of mammals became bimodal 40 million years ago and so remained until the end of the Pleistocene, when it was modified by megafauna extinction and became unimodal. We fitted two concurring models (a bimodal and a skewed unimodal) to the body mass distribution of global mammals and of each continent separately in tree time frames: Late Pleistocene, Holocene and Anthropocene. The results from both chapters, although from observation in different scales, suggest a pattern of niche packing on the Neotropics. This pattern is not biased by the recent megafauna extinction, but is due to the diversification of clades specific to the South American continent during its period of isolation. A high proportion of the species in these endemic groups is arboreal suggesting the importance of tropical forests in the diversification of mammals in this continent. Our results also suggest that the possible loss of endangered species in the Anthropocene will result in meaningful changes in Africa and Eurasia, two continents that where less affected by Pleistocene extinctions
64

O gênero Orthopyxis (Cnidaria, Hydrozoa) no Atlântico sul-ocidental: caracterização dos limites inter e intraespecíficos a partir de dados morfológicos e moleculares / The genus Orthopyxis of the southwestern Atlantic: evaluation of inter and intraspecific boundaries using morphological and molecular data

Cunha, Amanda Ferreira 21 October 2011 (has links)
Dentre os representantes de Campanulariidae, o gênero Orthopyxis é conhecido pela ampla plasticidade morfológica de suas espécies, bem como pela semelhança com o gênero Campanularia. Essas características levaram à descrição de muitas espécies nominais no Atlântico sul-ocidental e confusões com o gênero Campanularia, dificultando a identificação das espécies. Nesse contexto, este estudo teve os objetivos de (1) rever as ocorrências de Orthopyxis no Atlântico sul-ocidental, (2) compreender a variação morfológica intra-específica de Orthopyxis e delimitar suas espécies por meio de estudo morfométrico e molecular, e (3) compreender as relações entre os gêneros Orthopyxis e Campanularia no Atlântico sul-ocidental, levantando evidências morfológicas e moleculares que pudessem delimitá-los. A análise das sequências de DNA resultou no monofiletismo do gênero Orthopyxis e na delimitação das espécies O. sargassicola, O. integra e O. crenata, esta última um novo registro para o Atlântico sul-ocidental. As análises morfológicas permitiram identificar os caracteres informativos para a delimitação dessas linhagens, bem como a amplitude de variação dos caracteres morfológicos frequentemente utilizados para diagnose das espécies de Orthopyxis. Esse estudo aponta evidências morfológicas informativas para a delimitação dos gêneros, principalmente em relação ao cnidoma. O presente estudo do gênero Orthopyxis no Atlântico sul-ocidental poderá servir como modelo para o delineamento de outras pesquisas envolvendo a família Campanulariidae, ao mostrar que as espécies podem ser corretamente delimitadas a partir de análises morfológicas e moleculares. / Within the Campanulariidae, the genus Orthopyxis is known for its morphological plasticity and resemblance with the genus Campanularia. These characteristics have led to the description of numerous nominal species in the southwestern Atlantic, and also to considerable confusion with the genus Campanularia, making taxonomic identification very difficult. In this context, the goal of this study was to (1) review the occurrences of Orthopyxis in the southwestern Atlantic, (2) understand its intraspecific morphological variation and delimit species using morphological and molecular data, and (3) investigate the relationships between Orthopyxis and Campanularia to find morphological and molecular evidence for their delimitation. The molecular analyses resulted in a monophyletic Orthopyxis, and in the delimitation of O. sargassicola, O. integra, and O. crenata, the latter a new record for the southwestern Atlantic. The morphological analyses identified the characters that are most informative for the delimitation of these lineages, as well as the amplitude of morphological variation within the characters frequently used in the taxonomy of Orthopyxis.This study identified some morphological evidence for the delimitation of both genera, especially in relation to the cnidae. The present study of the genus Orthopyxis in the southwestern Atlantic can be used as a model for the delineation of future investigations of the family Campanulariidae, in the sense that species may be successfully delimited with an integrated morphological and molecular approach.
65

Morfologia e taxonomia de duas espécies de Notogynaphallia (Platyhelminthes, Tricladida, Terricola) do sul do Brasil

Lemos, Virgínia Silva 28 February 2003 (has links)
Made available in DSpace on 2015-03-05T16:20:41Z (GMT). No. of bitstreams: 0 Previous issue date: 28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho tem o objetivo geral de estabelecer o status taxonômico de duas espécies de Notogynaphallia, através de estudo morfológico e comparação com as espécies descritas para o gênero. Os espécimes foram coletados na Floresta Nacional de São Francisco de Paula, Rio Grande do Sul, Brasil, e, em laboratório, a morfologia externa foi estudada ao microscópio óptico, em espécimes vivos e fixados com formalina neutra. Fragmentos da região anterior, região pré-faríngea, faringe e do aparelho copulador foram separados para inclusão em paraplasto. Cortes seriados foram analisados ao microscópio óptico e o aparelho copulador, reconstruído. As duas espécies, Notogynaphallia pseudoceciliae sp. nov. e Notogynaphallia arturi sp. nov., apresentam corpo alongado com bordos paralelos e cinco estrias dorsais longitudinais escuras sobre fundo amarelado, sendo que Notogynaphallia arturi sp. nov. possui duas faixas laterais de pigmento castanho entre as estrias paramedianas e laterais. Em comparação com as espécies descrita / The general purpose of this dissertation is to verify the taxonomic status of two species of Notogynaphallia based on morphological studies and comparison with the described species of the genus. The specimens were collected at the National Forest of São Francisco de Paula, Rio Grande do Sul, Brazil, and, in the laboratory, the external morphology was studied from live and preserved animals. Fragments of the anterior region, pre-pharyngeal region, pharynx, and copulatory apparatus were embedded in Paraplast. Serial sections were analyzed by optical microscopy and the copulatory apparatus was reconstructed. The two species, Notogynaphallia pseudoceciliae sp. nov. and Notogynaphallia arturi sp. nov., show elongate bodies with parallel margins and the dorsum with five dark longitudinal stripes on a yellowish background. Additionally, N. arturi has two large lateral bands of brown pigment between the paramedian and lateral stripes. By comparing with the species described for the genus Notogynaphallia, we verified
66

Ecology of grazing lawns on tallgrass prairie

Shaffer, Monica January 1900 (has links)
Master of Science / Department of Biology / David C. Hartnett / A key feature of many grass-dominated ecosystems is the formation of grazing lawns, distinct patches characterized by intense grazing by mammalian herbivores and a dense short-statured grass canopy. A central concept of grazing lawns is the positive feedbacks between grazing animals and the grass resource. Intraspecific morphological plant trait changes and differences in plant species composition could both or individually play a role in the differences in characteristics of grazing lawns and neighboring tallgrass swards. I studied grazing lawns in North American tallgrass prairie to: a) test the ‘architectural shift hypothesis’ where continued grazing leads to changes in plant architecture resulting in more efficient foraging for grazers, creating a positive feedback that increases grazing and b) examine soil resource (nutrient and water) availability and grass nutritive quality on and off lawns to test the nutrient- and water-based pathways for grazing lawn maintenance. In a separate study (not reported here), we a) examined plant community structure on and off lawns to determine whether species composition differences account for the distinct grazing lawn characteristics and b) assessed effects of grazing lawn formation on tallgrass prairie plant species diversity. Several differences in morphological traits between dominant grasses on grazing lawns and tallgrass swards support the architectural shift hypothesis. For Sorghastrum nutans, Dichanthelium oligosanthes, and Pascopyrum smithii, leaf-to-stem ratio was twice as high on grazing lawns compared to surrounding matrix tallgrass vegetation and tiller branching was higher and culm internode lengths were shorter on grazing lawns for these species. However, Andropogon gerardii traits did not differ between grazing lawns and tallgrass vegetation. For all four species, above-ground tiller biomass and number of below-ground buds were both higher on grazing lawns. Overall, these morphological responses resulted in a higher grass canopy density (forage biomass per unit canopy volume) on grazing lawns and this increased grass canopy density in turn results in higher grazer foraging efficiency by increasing the amount of forage intake per bite and per unit time. D. oligosanthes, P. smithii, and S. nutans plants on grazing lawns had a significantly lower carbon-to-nitrogen ratio and higher nitrogen content than plants in the matrix tallgrass vegetation, while A. gerardii showed no significant difference in nitrogen content or in carbon-to-nitrogen ratio between grazing lawns and surrounding matrix tallgrass vegetation. With regards to the total grass canopy (all grass species combined), nitrogen content was significantly higher on grazing lawns compared to tallgrass vegetation for all three field seasons, 2016, 2017, and 2018. All measured soil nutrients, ammonium, nitrate, phosphorus, and sodium, were significantly higher on grazing lawns compared to soils of surrounding tallgrass swards, while water content showed no significant difference between grazing lawns and surrounding tallgrass vegetation. The results of this study strongly indicate that developmental and morphological shifts result in increased forage density and increased grazing efficiency on grazing lawns and that the frequent and intense activities of large grazers result in increased plant nitrogen content and lower C:N ratios in grasses on tallgrass prairie grazing lawns. Thus, at least two different mechanisms, plant architectural shifts and the nutrient-based pathway could both contribute to the positive feedbacks that encourage further grazing on lawns and grazing lawn maintenance on tallgrass prairie.
67

Performance, morphometric data and characteristics sleeve of sheep of race and santa inÃs brazilian somalis / AvaliaÃÃo do ganho de peso, desempenho, morfometria e caracterÃsticas de carcaÃa de ovinos das raÃas Santa InÃs e Somalis brasileiro, no Estado do CearÃ

Tatiana Gouveia Pinto Costa 20 August 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The objective present work was to evaluate the weight earnings, the morfometric and the characteristics of carcass of two genotype of lambs fedlot hair, Santa Ines and Somalis. Two experiments were accomplished: I - for weight earnings and morfometric of males and females, in confinement, and II - for evaluation of the characteristics of carcass of the males. In the experiment I, 10 males and 10 females of the race Santa Ines, and 10 males and 06 females of the race Somalis, were used, in a completely randomized design, in factorial outline 2x2 (two races and two sexes), which totaled four treatments. The adopted alimentary handling was the supply of pricked grass-elephant and concentrated (400g/head/day), distributed in the morning and in the afternoon. The experimental period had duration of 60 days, where every fifteen days the animals were heavy and accomplished the following weight measures: withers height (HW), crop height (CH),thorax height (TH), length of the body (LB), thoracic perimeter (TP), width of the thorax (WT), width of the croup (WC), croup length (CL), ileum width (IW) and width isqueum (IW). In the experiment II, a completely randomized design, where nine males Santa Ines and six Somalis were abated when they reached an average of 28 kg of alive weight. The appraised characteristics were, the alive discount weight (DW), hot carcass weigh (HCW), cold carcass weigh (CCW), hot carcass revenues (HCR) and cold (CCR), cooling loss (CL), internal length of the carcass (CLI) and the index of compactness of the carcass (ICC). In the cold carcass they were appraised the revenue of the following commercial cuts: neck, palette, whole loin, leg, chest, rack, rib and flank. There was significant difference (P<0.05) among the races and enter the sexes so much for the corporal weight as for most of the accomplished measures, of the 150 to the 210 days of age, and the race Santa Ines was superior the race Somalis, and the superior males the females. Among the carcass characteristics, the race Somalis presented smaller averages for PR and ML (P<0.05) than Santa Ines. There were not significant differences for the other carcass characteristics, as well as for the revenues of the cuts, among the appraised races. Santa Ines presented larger weights, weight measures, internal length of the carcass and it breaks for cooling than Somalis. With relationship to the revenue of the commercial cuts accomplished in the carcass the races sheeps Santa Ines and Somalis they were similar to each other / O objetivo presente trabalho foi avaliar o ganho de peso, a morfometria e as caracterÃsticas de carcaÃa de dois genÃtipos de ovinos deslanados, Santa InÃs e Somalis. Foram realizados dois experimentos: I â para ganho de peso e morfometria de machos e fÃmeas, em confinamento, e II â para avaliaÃÃo das caracterÃsticas de carcaÃa dos machos. No experimento I, foram utilizados 10 machos e 10 fÃmeas da raÃa Santa InÃs, e 10 machos e 06 fÃmeas da raÃa Somalis Brasileiros, em um delineamento inteiramente casualizado, em esquema fatorial 2x2 (duas raÃas e dois sexos), o qual totalizou quatro tratamentos. O manejo alimentar adotado foi o fornecimento de capim-elefante picado e concentrado (400g/ cabeÃa/dia), distribuÃdos pela manhà e à tarde. O perÃodo experimental teve duraÃÃo de 60 dias, onde a cada quinze dias os animais foram pesados e realizadas as seguintes medidas corporais: altura da cernelha (ACE), altura da garupa (AGA), altura do tÃrax (ATO), comprimento do corpo (CCO), perÃmetro torÃcico (PTO), largura do tÃrax (LTO), largura da garupa (LGA), comprimento da garupa (CGA), largura do Ãlio (LIL) e largura do Ãsquio (LIS). No experimento II, foi utilizado um delineamento inteiramente casualizado, onde nove machos Santa InÃs e seis Somalis foram abatidos quando atingiram uma mÃdia de 28 kg de peso vivo. As caracterÃsticas avaliadas foram, o peso vivo ao abate (PVA), peso da carcaÃa quente (PCQ), peso da carcaÃa fria (PCF), rendimentos de carcaÃa quente (RCQ) e fria (RCF), perda por resfriamento (PR), comprimento interno da carcaÃa (ML) e o Ãndice de compacidade da carcaÃa (ICC). Na carcaÃa fria foram avaliados o rendimento dos seguintes cortes comerciais: pescoÃo, paleta, lombo inteiro, perna, peito, carrÃ, costela e fraldinha. Houve diferenÃa significativa (p<0,05) entre as raÃas e entre os sexos tanto para o peso corporal como para a maioria das medidas realizadas, dos 150 aos 210 dias de idade, sendo que a raÃa Santa InÃs foi superior a raÃa Somalis, e os machos superiores as fÃmeas. Dentre as caracterÃsticas de carcaÃa, a raÃa Somalis apresentou menores mÃdias para PR e ML (p<0,05) do que a Santa InÃs. NÃo houve diferenÃas significativas para as demais caracterÃsticas de carcaÃa, como tambÃm para os rendimentos dos cortes, entre as raÃas avaliadas. A Santa InÃs apresentou maiores pesos, medidas corporais, comprimento interno da carcaÃa e quebra por resfriamento do que a Somalis. Quanto ao rendimento dos cortes comerciais realizados na carcaÃa as raÃas ovinas Santa InÃs e Somalis foram semelhantes entre si.
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Systematics, biogeography and studies of floral evolution in Gesneriaceae

Luna Castro, Javier Alejandro January 2017 (has links)
Understanding the processes that have affected the diversification of herbaceous plants is fundamental to understand how flowering plants evolve, how ecosystems form and to predict the effect of climate change and geological events in plant communities. Aiming to create a strong phylogenetic framework where biogeographic and morphological hypothesis can be tested a higher level dated phylogeny of Gesneriaceae was produced. Gesneriaceae is a good study group as it has variable floral morphology, a broad distribution throughout the tropics and subtropics - represented in all non-arid tropical and subtropical hotspots of biodiversity. There are evident differences between lineages in the numbers of species, and it is comparatively well studied compared with other asterid families. In this study a consolidated taxonomic hypothesis of Gesneriaceae is suggested based on a genus level phylogeny, the ages of the main lineages of the family are presented, the effect of geological events are explored, the geographic origin of lineages are suggested and an insight into the effect of floral morphology on the evolution of the family is given. Limiting the taxonomic scope and focusing on a single family should help us better understand how flowering plants diversify.
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Algas gracilarióides (Gracilariaceae, Rhodophyta) na costa brasileira: uma abordagem morfológica e molecular / Gracilarioid algae (Gracilariaceae, Rhodophyta) along the brazilian coast: a morphological and molecular approach

Costa, Emmanuelle da Silva 25 March 2013 (has links)
Devido à sua importância ecológica e econômica as algas gracilarióides são alvo de diversos estudos desenvolvidos por pesquisadores de todo o mundo. No entanto, ainda persistem dificuldades em relação à taxonomia do grupo, que se tornam ainda mais problemáticas no que diz respeito às espécies achatadas, ainda pouco estudadas quando comparadas às espécies cilíndricas. Essa dificuldade taxonômica é devida principalmente a um elevado número de espécies, algumas com ampla distribuição geográfica e a morfologia simples e plástica. Devido à grande dificuldade em se identificar as espécies de Gracilariaceae utilizando-se caracteres morfológicos, o uso de dados moleculares tem se mostrado taxonomicamente útil, e em alguns casos essencial, na discriminação das espécies. Neste trabalho foram geradas sequências inéditas de dois marcadores moleculares do tipo DNA \"barcodes\" (UPA e cox1) para diversas espécies, incluindo espécies de ocorrência na costa brasileira e algumas espécies de outras localidades mantidas em cultura no Banco de Germoplasma da USP. A morfologia para os táxons encontrados foi analisada e o gene rbcL foi sequenciado para permitir a comparação com outras sequências nos bancos de dados e para a construção de uma filogenia para o grupo. Foram geradas 289 sequências para 135 amostras. DNA \"barcodes\" foram gerados para todas as 50 amostras do banco de germoplasma. Em adição, o rbcL foi sequenciado para os agrupamentos de cox1/UPA totalizando 14 amostras. Treze espécies diferentes foram identificadas no banco de germoplasma combinando análises morfológicas anteriores e análises moleculares. Nossas análises indicaram que cox1 e UPA foram marcadores eficientes para a delineação das espécies de Gracilariaceae e tornaram o banco ainda mais útil para pesquisas futuras. Em relação às espécies de Gracilariaceae de ocorrência na costa brasileira, a utilização dos marcadores moleculares permitiu a identificação de alguns táxons, dos quais três são novas ocorrências para o Brasil: Gracilaria damaecornis, Gracilaria hayi e Gracilariopsis Silvana. Baseado em dados morfológicos e moleculares concluímos que Gracilaria tepocensis citada para a região Sul e Sudeste, não ocorre no Brasil tratando-se de Gracilaria isabellana, anteriormente citada para o Brasil como Gracilaria lacinulata. Concluímos também que os marcadores moleculares do tipo DNA \"barcode\" são eficientes na identificação das Gracilariaceae de talo cilíndrico cujos caracteres morfológicos diagnósticos pouco contribuem no reconhecimento: Gracilaria birdiae, Gracilaria caudata e Gracilaria córnea, ao contrário de estudos pretéritos que utilizaram outros marcadores moleculares mais conservados (SSU rDNA). A utilização de ferramentas moleculares na identificação e separação das Gracilariaceae de talo achatado mostrou-se bastante eficiente e necessária, uma vez que os caracteres morfológicos de valor taxonômico pouco contribuem na correta identificação. Dessa forma foi possível identificar 19 táxons de Gracilariaceae utilizando-se marcadores moleculares, dos quais 15 correspondem as Gracilariaceae de talo achatado / Due to its ecological and economic importance gracilarioid algae are targets of several studies developed by researchers around the world. However, there are still difficulties for the taxonomy of this group, which become even more problematic with regard to the flattened species, which are poorly studied species when compared to cylindrical. This taxonomic difficulty is primarily due to a high number of species, some with broad geographic distribution and a simple and plastic morphology. Due to great difficulty in identifying the species of Gracilariaceae using morphological characteristics, molecular data has shown to be taxonomically useful, and in some cases essential to discriminate species. In this study we generated novel sequences of two DNA \"barcodes\" (UPA and cox1) molecular markers for several species, including species occurring on the Brazilian coast and some species from other localities maintained in culture in the Germplasm Bank of USP. The morphology of the taxa was analyzed and the rbcL gene was sequenced to enable comparison with other sequences in the databases and to construct a phylogeny for the group. A total of 289 sequences were generated for 135 samples. DNA \"barcodes\" were generated for all 50 samples of the germplasm bank. In addition, the rbcL was sequenced for 14 representatives of the cox1/UPA groups. Thirteen different species were identified in the germplasm bank combining previous morphological and molecular analyses. Our analysis indicated that cox1 and UPA markers were efficient for the delineation of Gracilariaceae species and made the bank even more useful for future research. Regarding Gracilariaceae species occurring on the Brazilian coast, the use of molecular markers allowed the identification of some taxa, of which three are new records for Brazil: Gracilaria damaecornis, Gracilaria hayi and Gracilariopsis silvana. Based on morphological and molecular data Gracilaria tepocensis cited for the South and Southeast of Brazil does not occur, and is in fact Gracilaria isabellana previously cited for Brazil as Gracilaria lacinulata. We also conclude that the DNA \"barcode\" molecular markers are effective in identifying Gracilariaceae presenting cylindrical thallus whose diagnostic morphological characters little contribute for its recognition: Gracilaria birdiae, Gracilaria caudate and Gracilaria cornea, unlike other studies that used more conserved molecular markers (SSU rDNA). The use of molecular tools in the identification and separation of flattened Gracilariaceae proved to be very efficient and necessary, since the morphological characters contribute little for the correct identication. Thus, in this work it was possible to identify 19 taxa of Gracilariaceae using molecular markers, of which 15 corresponds flattened species
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Morphological and genetic diversity analysis in selected vernonia lines

Ramalema, Seganka Piet January 2007 (has links)
Thesis (M.Sc. (Crop science)) --University of Limpopo, 2007 / Vernonia (Vernonia galamensis) is a new potential industrial oilseed crop. The seeds of this crop contain unusual naturally epoxidised fatty acids which are used in the production of various industrial products. The objective of this study was to evaluate the genetic diversity of selected vernonia lines in Limpopo Province through morphological, seed oil content and RAPD DNA markers. Significant differences were observed for days to 50 % flowering (93 - 140 days), plant height (141.80 - 166.33 cm), number of productive primary heads (29 - 60 head/plant), number of productive secondary heads (12 - 30 head/plant), thousand seed weight (1.85 - 3.52 g) and seed yield (454.44 - 786.85 kg/ha) between lines. Further results from oil analysis showed differences in the contents of seed oil (22.4 - 29.05%), vernolic acid (73.09 - 76.83%), linoleic acid (13.02 - 14.05%), oleic acid (3.77 - 5.28%), palmitic acid (2.48 - 2.98%) and stearic acid (2.26 - 2.75%). Among 13 RAPD DNA primers screened, primer OPA10 amplified DNA samples and resulted in four distinct groupings among tested lines. Four promising lines were selected viz. Vge-16, Vge-20, Vge-27 and Vge-32 displaying greater seed yield, increased vernolic acid content and reduced number of days to 50 % flowering. / National Research Foundataion

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