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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.
41

Shading in ecophysiology, production and cuttings red pitaya / Sombreamento na ecofisiologia, produÃÃo e propÃgulos de pitaia vermelha

Edmilson Igor Bernardo Almeida 10 April 2015 (has links)
nÃo hà / Em pomares comerciais de pitaia vermelha, no CearÃ, à comum a presenÃa de plantas com cladÃdios amarelados, principalmente nas Ãpocas mais quentes do ano. Diante disso, realizou-se um estudo com o intuito de avaliar a interferÃncia do sombreamento sobre o crescimento, anatomia, pigmentos fotossintÃticos, trocas gasosas e produÃÃo de pitaia vermelha. O delineamento experimental foi em blocos casualizados (DBC), com cinco tratamentos, cinco repetiÃÃes e duas plantas por parcela. Os tratamentos foram constituÃdos pelos nÃveis de sombreamento: pleno sol, 35, 50; 65 e 80% de sombreamento. As avaliaÃÃes foram divididas em duas etapas (180 e 365 dias), de modo a observar o efeito dos tratamentos sobre o crescimento inicial e o primeiro ciclo produtivo da cultura. A pitaia vermelha, inicialmente (aos 180 dias), apresentou melhor desempenho sob condiÃÃes de sombreamento, especialmente a 35% de sombra. No entanto, ao decorrer do seu ciclo, as plantas cultivadas a pleno sol foram as mais produtivas, com nÃmero de frutos, duas vezes superior Ãs sombreadas. Para as condiÃÃes edafoclimÃticas de Fortaleza (CE) recomenda-se a produÃÃo de mudas em condiÃÃes sombreadas de 35% e a implantaÃÃo do pomar de pitaia vermelha a pleno sol. / In commercial orchards red dragon fruit, CearÃ, is common the presence of plants with yellow cladodes, especially in the warmer seasons. Therefore, we carried out a study in order to evaluate the effect of shading on growth, anatomy, photosynthetic pigments, gas exchange and production of red pitaya. The experimental design was randomized blocks (DBC), with five treatments, five replicates and two plants per plot. The treatments were constituted by shading levels: full sun, 35, 50; 65 and 80% shading. The evaluations were divided into two stages (180 and 365 days) in order to observe the effect of treatments on initial growth and production cycle of the first crop. The red dragon fruit, initially (at 180 days), performed better under shade conditions, especially the 35% shade. However, the course of its cycle, plants grown in full sun were the most productive, with number of fruits, twice the shaded. To soil and climatic conditions of Fortaleza (CE) is recommended to grow seedlings in shaded conditions 35% and the implementation of the red dragon fruit orchard in full sun.
42

Macroecological patterns of plant species and anthropogenic activities

Correa Cano, María Eugenia January 2015 (has links)
The study of macroecology not only identifies patterns in the distribution and abundance of species at large spatial and temporal scales, it also gives insight into the processes underlying those patterns. The contribution of this work is not limited to helping develop the field of ecology per se, but also provides important insights into the understanding of large scale processes like climate change, the spread of introduced species, pest control and how increasing pressure from anthropogenic activities threatens biodiversity and ecosystem services. During the first decade following its formal inception, most of the progress in macroecology was made through studies of animal species, and research into plant species continues to lag far behind. This thesis contributes to the study of the macroecology of plant species by examining some selected macroecological patterns that have been studied only for animal species and by including an important issue that might have significant effects on diverse macroecological patterns, namely anthropogenic activities. The second and third chapters of the thesis address the generalised individuals-area relationship (GIAR) and the patch individuals-area relationship (PIAR), two macroecological relationships not previously explored for plant species. I show for the first time the existence of negative GIARs at the intraspecific and interspecific levels in plant species, similar to those documented for animal species. Unlike animal species, I did not find a broadly consistent intraspecific PIAR in plant species; more than half of the tested species showed negative PIARs. The resource concentration hypothesis may help explain those positive PIARs that were observed. The fourth chapter considers the effect of past human activities on current patterns of plant species richness at a landscape scale. Using a detailed database on the historical anthropogenic activities for Cornwall, U.K., I examine the relationship between species richness and the area covered by each historical land-use at two different spatial resolutions (10km x 10km and 2km x 2km). I find that at the 10km x10km scale human activities carried out since the 17th and 19th centuries explain an important proportion of the variation in current plant species richness. In contrast, a model at 2km x 2km scale with upland woods and the total land area of a grid cell explain only 5% of the variation. The fifth and sixth chapters focus on how artificial light at night (ALAN), which has increasingly come to attention as a significant anthropogenic pressure on species, is interacting with the distributions of plant species. In the fourth chapter, I consider the plant family Cactaceae to determine the proportion of the global distribution ranges of species that is being influenced by ALAN, and how this changes with the size of these distribution ranges and over a 21-year period (1992 to 2012). I found that >80% of cacti species are experiencing ALAN somewhere in their distribution range, and that there is a significant upward trend in ALAN in the ranges of the vast majority of species. For the sixth chapter, I consider similar issues for the threatened plant species of Britain, exploiting new remote sensing imagery of nighttime lighting at a very fine spatial resolution (c.340x340m2). Only 8% of Britain is free of artificial light at night and in consequence a high number of threatened plant species have a high proportion of their range under some influence of ALAN.
43

Estudo da funcionalidade de esp?cies comest?veis do semi?rido nordestino e estrat?gias para sua utiliza??o como ingredientes para fins aliment?cios

Souza, Rosane Li?ge Alves de 01 August 2014 (has links)
Made available in DSpace on 2014-12-17T15:01:58Z (GMT). No. of bitstreams: 1 RosaneLAS_TESE.pdf: 1312520 bytes, checksum: 82a532d76af3f2c9d016ea88510460fc (MD5) Previous issue date: 2014-08-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia f?cus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of caj? and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend caj?-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and caj? flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use / O semi?rido brasileiro configura-se por condi??es clim?ticas e de solo desfavor?veis e vegeta??o resistente a longos per?odos de estiagem. As esp?cies de cact?ceas nativas ou adaptadas ? regi?o, como o figo da ?ndia (Opuntia f?cus indica) e facheiro (Philosocereus pachycladus Ritter), t?m frutos comest?veis pouco conhecidas. Al?m destas esp?cies, a leguminosa algaroba ? uma mat?ria-prima com caracter?sticas ainda pouco investigadas do ponto de vista tecnol?gico e teor de subst?ncias bioativas. Desta forma, este trabalho objetivou realizar a caracteriza??o f?sico-qu?mica, bioativa e funcional da polpa das cact?ceas figo da ?ndia e facheiro e da farinha de algaroba. O estudo incluiu a determina??o do teor de compostos fen?licos, identifica??o e quantifica??o das betala?nas por HPLC-DADESI- MS, al?m da investiga??o da atividade antioxidante e inibi??o das enzimas alfa-amilase e alfa-glicosidase, utilizando extratos aquosos e etan?licos obtidos a partir das esp?cies avaliadas. Como estrat?gias de aproveitamento, elaborou-se suco misto do figo da ?ndia, biofilmes a partir do facheiro e barra de cereal a partir da farinha de algaroba. A caracteriza??o do figo da ?ndia revelou baixa acidez e elevada do?ura, quando comparada ao facheiro. O fruto do Philosocereus pachycladus Ritter, por sua vez, apresentou maior conte?do prot?ico e de cinzas. No entanto, a maior fra??o proteica e a??cares est? contida na farinha de algaroba. O conte?do de fibra alimentar total (FAT) revelou a potencialidade da farinha de Prosopis juliflora para atuar como reguladora da fun??o intestinal. O teor de fen?lico total para extratos aquosos e etan?licos variaram de 3,87 a 16,21 mg GAE/100g para a farinha de algaroba, 79,24 a 110,20 mg GAE/100g para o figo da ?ndia e facheiro 412,23 a 539,14 mg GAE/100g. O extrato etan?lico a 70% do figo da ?ndia apresentou elevada atividade antioxidante, por?m o meior percentual fen?lico foi observado no facheiro. Em rela??o ? inibi??o enzim?tica, o melhor desempenho foi observado em extratos do figo da ?ndia, os quais exibiram inibi??o moderada para as duas enzimas estudadas, enquanto que n?o foi identificada inibi??o glicol?tica para o extrato aquoso de facheiro. O presente trabalho mostra, pela primeira vez na literatura, resultados in?ditos sobre a funcionalidade do facheiro, que incluem a presen?a das betala?nas betacianina e isobetanina na polpa desse fruto. No que diz respeito aos produtos desenvolvidos, as caracter?sticas sensoriais que melhor descreveram o suco misto de figo da ?ndia e caj? foram do?ura, acidez, cor amarela-alaranjada, corpo, turbidez e aroma de caj?. A an?lise discriminativa da barrinha de cereal elaborada com e sem farinha de algaroba mostrou que apenas o atributo textura foi diferente estatisticamente (p < 0,05) para as formula??es testadas. Os resultados tamb?m indicam que a adi??o do extrato do facheiro n?o modificou visualmente as caracter?sticas dos biofilmes. De maneira geral, o presente estudo revela as caracter?sticas f?sico-qu?micas e bioativas desses vegetais abundantemente encontrados na caatinga brasileira, mas ainda pouco explorados sob pontos de vista tecnol?gico e comercial, bem como sugere alternativas de aproveitamento para tais esp?cies
44

Germinação de sementes e aspectos etnobotânicos de Melocactus violaceus Pfeiff no estado de Sergipe

Imidio, Andreza Messias 23 February 2017 (has links)
The Melocactus violaceus Pfeiff is a specie belonging to the Cactaceae family, endemic in Brazil and typical of the Restinga ecosystem on the Brazilian coast. Popularly known as the head of the monk, in Sergipe is one of the most recorded species in the Restinga of the state, but its status is vulnerable (VU) according to international criteria of Union for Nature Conservation due to the strong utilitarianism and fragmentation of its species occurs. Allied to these factors is the vegetative phase of the very long species, a decade until it begins to produce fruits, which further aggravates its vulnerability. The objective of this work was to identify the Melocactus violaceus in its habitat and its importance in the state of Sergipe through bibliographic review, germination tests in substrate and in vitro aiming the production of seedlings, and to develop ethnobotanical study. For the germination tests, the evaluated variables were the germination speed index (IVG) and the percentage of germination. The experiments of germination in substrate were carried out in laboratory and greenhouse. The substrate used was washed sand and 1: 1 vegetable soil with seeds previously soaked in different time intervals. In the laboratory, there were significant differences in IVG values and percentage of germination. In the greenhouse, there was a significant difference only for the IVG variable. For in vitro germination, the basic medium used was composed of the Murashige & Skoog salts formulation. This experiment was composed of two imbibition treatments: seeds imbibed in distilled water (T1) and seeds embedded in gibberellin (T2) at concentrations of 0; 0.5; 1.0; 2.0 and 4.0 mgL-1. In the results obtained in treatment 1 there were significant differences in Germination Percentage and IVG, however, in treatment 2 there was a significant difference only in IVG according to the Scott-Knott test at 5% significance. The substrate germination treatments for the M. violaceus seeds in the greenhouse showed better results in the germination percentage and in the IVG, with periods of imbibition of more than 30 minutes. The treatments with germination in vitro were efficient and reached more than 40% of germinated seeds, but in the treatments with gibberellin the evaluated concentrations of the phytorregulator did not present significant difference on the percentage of germination. The ethnobotanical study was developed with 60 people in the County of Pacatuba, Pirambu and Aracaju, on the knowledge and uses of M. violaceus. In each municipality, 20 people were interviewed through a semi-structured road map. The profiles of the interviewed population, the way of knowledge was divided in the communities, as well as the categories of use were identified. The categories of use identified were ornamental, medicinal, mystical and food. / O Melocactus violaceus Pfeiff é uma espécie pertencente à família Cactaceae, endêmica no Brasil e típica do ecossistema Restinga no litoral brasileiro. Conhecida popularmente como cabeça-de-frade, em Sergipe é uma das espécies mais registradas nas Restinga do estado, porém encontra-se com status de vulnerável (VU) segundo critérios da União Internacional de Conservação da Natureza devido ao forte utilitarismo e fragmentação de seu habitat nos locais onde a espécie ocorre. Aliada a esses fatores está a fase vegetativa da espécie muito longa, uma década até começar a produzir frutos, o que agrava ainda mais sua vulnerabilidade. Este trabalho teve como objetivos identificar o Melocactus violaceus em seu habitat e sua importância no estado de Sergipe através de revisão bibliográfica, realização de testes de germinação em substrato e in vitro visando à produção de mudas, e desenvolver estudo etnobotânico. Para os testes de germinação, as variáveis avaliadas foram o índice de velocidade de germinação (IVG) e o Percentual de germinação. Os experimentos de germinação em substrato foram realizados em laboratório e casa-de-vegetação. O substrato utilizado foi composto por areia lavada e terra vegetal na proporção de 1:1 com sementes previamente embebidas em diferentes intervalos de tempo. Em laboratório, houve diferenças significativas nos valores de IVG e na porcentagem de germinação. Em casa-de-vegetação, houve diferença significativa apenas para a variável IVG. Para a germinação in vitro, o meio básico utilizado foi composto pela formulação de sais de Murashige & Skoog. Este experimento foi composto por dois tratamentos de embebição: sementes embebidas em água destilada (T1) e sementes embebidas em giberelina (T2) nas concentrações de 0; 0,5; 1,0; 2,0 e 4,0 mgL-1. Nos resultados obtidos no tratamento 1 houve diferenças significativas nos valores de Porcentagem de Germinação e IVG, entretanto, no tratamento 2 houve diferença significativa somente no IVG de acordo com o teste Scott-Knott a 5% de significância. Os tratamentos de germinação em substrato para as sementes de M. violaceus na casa-de-vegetação apresentaram melhores resultados na porcentagem de germinação e no IVG, com períodos de embebição superiores a 30 minutos. Os tratamentos com germinação in vitro mostraram-se eficientes e alcançaram mais de 40% de sementes germinadas, porém nos tratamentos com giberelina as concentrações avaliadas do fitorregulador não apresentaram diferença significativa sobre a porcentagem de germinação. O estudo etnobotânico foi desenvolvido com 60 pessoas nos municípios de Pacatuba, Pirambu e Aracaju, sobre o conhecimento e usos do M. violaceus. Em cada município foram entrevistadas 20 pessoas através de um roteiro semiestruturado. Foram identificados os perfis da população entrevistada, a forma como o conhecimento está dividido nas comunidades, assim como as categorias de uso. As categorias de uso identificadas foram ornamental, medicinal, místico e alimentício.
45

Cryptic Dioecy in <em>Consolea</em> (Cactaceae): Sex Determination & Evolutionary Implications

Strittmatter, Lara I. 15 August 2006 (has links)
No description available.

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