Thesis (M.A.)--Trinity Evangelical Divinity School, 1995. / Abstract. Includes bibliographical references (leaves 114-118).

How specialist bees distinguish their host plants from co-blooming non-hosts is not well understood, but it is thought that they may be physiologically limited in their ability to recognize the majority of visual and olfactory cues presented by flowering plants. Species in the genus Diadasia collect pollen from just one of five plant families: Cactaceae, Malvaceae, Onagraceae, Asteraceae, and Convolvulaceae. Assuming a common ancestor for all Diadasia specialized on just one plant, this indicates host-switches in the past, and an ability to recognize more than one flowering plant. I hypothesized that host plants of Diadasia share the same visual and olfactory cues, thus enabling past host-switching to novel plant families, and that co-blooming non-hosts are highly dissimilar in terms of scent and visual appearance. I determined the compounds associated with the scent of Malvaceae and Cactaceae host flowers of North American Diadasia. I also evaluated visual cues for these flowers by measuring their full spectrum of reflected wavelengths, as well as select morphometric characters. I determined whether host flowers, regardless of taxa, were more similar to each other than non-hosts that were co-blooming and attractive to other bee species. Finally, I performed electroantennographic and behavioral experiments to assess the relative importance of these cues (visual and olfactory) in natural settings. Diadasia host plants share some chemical and visual characteristics that may in part explain the radiation of this group onto these particular hosts. First, host plants share a suite of scent compounds that are among the least variable across species. Many of these elicited antennal responses and did not decrease visitation when applied to host flowers. In contrast, some compounds produced by non-host flowers are detectable to Diadasia, but Diadasia are repelled by them when they are applied to host flowers. Diadasia host flowers do not share a color profile in common, but there is more reflectance in the bee-uv range as compared to other regions of the light spectrum. Also, Diadasia host flowers have a more contrasting central area that is relatively larger than in non-hosts.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-05-25T13:03:29Z No. of bitstreams: 1 Morganna Pollynne Nobrega Pinheiro.pdf: 1645144 bytes, checksum: 5febf32ecd170831a3811cfa9b927d78 (MD5) / Made available in DSpace on 2016-05-25T13:03:29Z (GMT). No. of bitstreams: 1 Morganna Pollynne Nobrega Pinheiro.pdf: 1645144 bytes, checksum: 5febf32ecd170831a3811cfa9b927d78 (MD5) Previous issue date: 2015-05-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A growing number of studies reports the identification and characterization of genes associated with flower bud and the isolation of its regulatory regions. These strands are helping to unravel a number of issues concerning the regulation and cellular interactions, thus generating a great impact on improving various plant species. In cotton (Gossypium hirsutum) these studies have contributed substantially in obtaining of genetically modified GM plants, holders of genes for resistance to herbicides and lepidopteran, and are becoming the possibility of increasing the control efficiency against target pests that act directly in floral structures and / or even enhance the expression of the coloring effect of the fibers. Different techniques are available for functional genomics analysis, among the most adopted is the construction of expressed sequence tags (ESTs) libraries that allows to identify which RNAs are expressed in an organism at a given time. Using this methodology in a previous study, were characterized by in silico analyzes genes involved in reproductive functions of cotton, some of whom expressed in male and female gametophytes. At that moment, from RT-PCR assays and qRT-PCR, six genes (GhASH, GhFIB010, GhGLUC, GhMYB, GhOVU and GhUDP) were investigated for the temporal expression during ontogeny flower bud, at stages 2-4 6-8, 10, 12, 14-16, and 18-20 mm. All of the genes investigated were active in floral buds of different sizes and in different expression levels, however, the highest level observed was 10 mm, except for gene GhASH with the highest expression in 10 to 16 mm. In these stages the cotton bud is in intense cellular activity including reduced cell wall formation of the complete embryonic sac, appearance and degeneration of the antipodes suggesting that these genes that may be involved in the formation and development or ovules, pollen, pollen tube, as well as on fibers. The gene was GhASH which also had the highest level of expression in all stages compared to other genes. Due to the regulation of these genes involved precursor steps, prior to anthesis and possibly runs through the final process of maturation, we proceeded further a study of tissue expression in organs flowering cotton (bracts, sepals, petals, ovules, anthers and fibers with 8, 10 and 18 DPA) to understand the interrelationships of the genes involved in the reproductive phase and its performance during development. It was found that all genes showed equivalent expression with its features, described in the databases. Analyses of gene activity for genes GhASH, GhOVU and GhGLUC proposed performances in training and / or development of all floral organs especially in pollen grains, pollen tube and anthers. For genes involved in fiber GhMYB, GhFIB010, GhUDP expression was observed for all studied growth stage, suggesting that are directly involved in elongation phase of the fibers, this phase has been widely investigated since the length of the cotton fiber is a key feature in determining the quality and yield. Additional studies to functional characterization of promising genes and isolation of their regions upstream become necessary in order to contribute to the progress and molecular breeding of this oilseed. / É crescente o número de pesquisas que reportam a identificação e caracterização de genes associados ao botão floral, bem como no isolamento de suas regiões regulatórias. Estas vertentes vêm auxiliando na elucidação de várias questões relativas à regulação e das interações celulares, gerando assim um grande impacto no melhoramento de várias espécies vegetais. Em algodão (Gossypium hirsutum) estes estudos têm contribuido substancialmente na obtenção de plantas geneticamente modificadas (GM), detentoras de genes para resistência a herbicidas e lepidópteros, e reveste-se na possibilidade de aumentar a eficiência de controle contra pragas alvo que atuam diretamente em estruturas florais e/ou ainda, potencializar o efeito de expressão na coloração das fibras. Diferentes técnicas estão disponíveis para a análise de genômica funcional, entre as mais adotadas está a construção de bibliotecas de curtas sequêcias expressas (ESTs) que permite identificar quais RNAs mensageiros estão sendo expressos num organismo em um determinado momento. Com o uso desta metodologia em estudo anterior, foram caracterizados por análises in silico genes envolvidos em funções reprodutivas do algodoeiro, alguns dos quais expressos nos gametófitos masculino e feminino. Nesse momento, a partir de ensaios de RT-PCR e qRT-PCR, seis genes (GhASH, GhFIB010, GhGLUC, GhMYB, GhOVU e GhUDP) foram investigados quanto à expressão temporal durante a ontogenia do botão floral, nos estádios de 2-4, 6-8, 10, 12, 14-16 e 18-20 mm. Todos os genes investigados apresentaram atividade nos diferentes tamanhos dos botões florais e com níveis diferenciados de expressão, contudo, o maior nível foi observado no tamanho de 10 mm, com exceção do gene GhASH que apresentou maior expressão nos botões de 10 a 16 mm. Nestes estádios o botão encontra-se em atividade celular intensa incluindo redução da parede celular, formação dos sacos embrionários completos, surgimento e degeneração das antípodas, sugerindo que esses genes podem estar envolvidos na formação e ou desenvolvimento de óvulos, grãos de pólen, tubo polínico, como também em fibras. O gene GhASH também apresentou o maior nível de expressão em todos os estádios do botão floral quando comparado aos demais genes. Em função da regulação desses genes envolverem etapas precursoras, que antecedem a antese e que, possivelmente perpassa o processo final de maturação, procedeu-se adicionalmente um estudo de expressão tissular em órgãos floríferos do algodão (brácteas, sépalas, pétalas, óvulos, anteras e fibras com 8, 10 e 18 DPA) de modo a entender as interrelações dos genes envolvidos na fase reprodutiva e sua atuação durante o desenvolvimento. Verificou-se que todos os genes apresentaram expressão equivalente com suas funcionalidades descritas nos bancos de dados. As análises da atividade gênica para os genes GhASH, GhOVU e GhGLUC propuseram atuações na formação e/ou desenvolvimento de todos os órgãos florais sobretudo em grãos de pólen, tubo polínico e anteras. Para os genes envolvidos nas fibras, GhMYB, GhFIB010, GhUDP, a expressão foi observada para todas as três fases fenológicas estudadas, sugerindo assim que estejam envolvidos diretamente na fase de elongação das fibras, fase que tem sido bastante investigada, uma vez que o comprimento das fibras de algodão é uma característica chave de determinação da qualidade e rendimento. Estudos adicionais para caracterização funcional dos genes promissores e isolamento de suas regiões upstream tornam-se necessários a fim de contribuir com os avanços do melhoramento genético e molecular dessa oleaginosa.

Submitted by (edna.saturno@ufrpe.br) on 2016-06-15T15:14:54Z No. of bitstreams: 1 Ana Cecilia Ribeiro de Castro.pdf: 1325909 bytes, checksum: 2a37e84a4a4736120bd0856f109fd038 (MD5) / Made available in DSpace on 2016-06-15T15:14:54Z (GMT). No. of bitstreams: 1 Ana Cecilia Ribeiro de Castro.pdf: 1325909 bytes, checksum: 2a37e84a4a4736120bd0856f109fd038 (MD5) Previous issue date: 2007-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In order to describe Heliconia psittacorum x Heliconia spathocircinata ‘Golden Torch’ nutritional deficiency symptoms, evaluate macronutrients omission effects on growth, first flower stem characteristics and longevity, greenhouse experiments were conducted under the lacking element technique. The lacking macronutrients treatment reduced growth, shoot tillering and dry weight production compared to the complete nutrient solution treatment. Nutrient symptons occurred as follows: N,K, P, Mg and S. Deficiency symptoms were general chlorosis at – N treatment; slight chlorosis at – P and – S; dark green leaves and necrosis at – K; border chlorosis and necrosis at – Mg. The lack of Ca did not show any visual symptoms.The omission of each macronutrient in the nutritive solution reduced its respective concentration in the plant. Among the evaluated leaves, the concentration tended to a greater reduction in the third leaf. Based on the third leaf macronutrients contents on g kg-1 at the first emitted shoot, the following values were found for complete solution treatment and lacking nutrients treatments, respectively: N =16,28 e 7.87; P = 1,49 e 0, 68; K = 32,68 e 3,26; Ca = 8,76 e 3,38; Mg = 1,75 e 0.70; S = 6,00 e 1,82, at 90 days e N = 24,40 e 5,32; P = 1,32 e 0,46; K = 12,88 e 3,50; Ca = 4,58 e 0,97; Mg = 0,98 e 0,62; S = 4,44 e 1,00, at blooming period. The Heliconia psittacorum x H. spathocircinata ‘Golden Torch’ inflorescence produced under N omission showed a pale orange color and floral stem deformation. N, P and K omission affected stem length, stem diameter, inflorescence length and postharvest longevity, which are considered to be important market characteristics. Macronutrients deficiency reduced floral stem production. Greater postharvest longevity is to be found at higher floral stem dry matter. Carbohydrate ratio in underground parts has positive correlation with floral stem dry matter. / Com o objetivo de descrever os sintomas de deficiências nutricionais, avaliar o efeito da omissão de macronutrientes no crescimento, características da primeira haste floral e longevidade pós-colheita de Heliconia psittacorum x Heliconia spathocircinata cultivar Golden Torch foram conduzidos experimentos em casa de vegetação, mediante técnica do elemento faltante. Os sintomas de deficiência surgiram na seguinte ordem de ocorrência: N, K, P, Mg e S. Os sintomas foram: clorose generalizada em – N; clorose em – P e em – S; folhas verde-escuras e necrose em – K e; clorose ao longo dos bordos com necrose em – Mg. A omissão de Ca não acarretou sintomas visíveis. As omissões dos macronutrientes reduziram o crescimento, perfilhamento e produção de massa seca nas folhas e parte subterrânea das plantas quando comparadas as do tratamento completo. A omissão de cada macronutriente na solução nutritiva ocasionou a redução do seu respectivo teor na planta. Entre as folhas avaliadas, houve tendência à redução destes teores de forma mais acentuada na 3ª folha. Com base nos teores em g kg-1 dos macronutrientes na 3ª folha do primeiro perfilho emitido, encontraram-se os seguintes valores nos tratamentos completo e com omissão, respectivamente:N = 16,28 e 7.87; P = 1,49 e 0, 68; K = 32,68 e 3,26; Ca = 8,76 e 3,38; Mg = 1,75 e 0.70; S = 6,00 e 1,82, na fase vegetativa e N = 24,40 e 5,32; P = 1,32 e 0,46; K = 12,88 e 3,50; Ca = 4,58 e 0,97; Mg = 0,98 e 0,62; S = 4,44 e 1,00, na floração. A omissão de N, P e K reduziram o comprimento e o diâmetro da haste, bem como, o comprimento e longevidade pós-colheita da inflorescência características importantes para comercialização. As inflorescências produzidas no tratamento com omissão de N apresentaram coloração laranja pálido e deformação nas hastes florais. As deficiências de macronutrientes diminuiram, ainda, a produção de hastes florais. Foi observada uma maior durabilidade pós-colheita em Hastesflorais com maior massa seca e diâmetro. O teor de carboidrato na parte subterrânea teve correlação positiva com a massa seca encontrada na haste floral.

The response of tropical forests to anthropogenic climate change is critically important to future global carbon budgets, yet remains highly uncertain. Here, we investigate how precipitation, temperature, solar radiation and dry-and wet-season lengths are related to annual tree growth, flower production, and fruit production in three moist tropical forest tree species using long-term datasets from tree rings and litter traps in central Panama. We also evaluated how growth, flower, and fruit production were interrelated. We found that growth was positively correlated with wet-season precipitation in all three species: Jacaranda copaia (r = 0.63), Tetragastris panamensis (r = 0.39) and Trichilia tuberculata (r = 0.39). Flowering and fruiting in Jacaranda were negatively related to current-year dry-season rainfall and positively related to prior-year dry-season rainfall. Flowering in Tetragastris was negatively related to current-year annual mean temperature while Trichilia showed no significant relationships of reproduction with climate. Growth was significantly related to reproduction only in Tetragastris, where it was positively related to previous year fruiting. Our results suggest that tree growth in moist tropical forest tree species is generally reduced by drought events such as those associated with strong El Nino events. In contrast, interannual variation in reproduction is not generally associated with growth and has distinct and species-specific climate responses, with positive effects of El Nino events in some species. Understanding these contrasting climate effects on tree growth and reproduction is critical to predicting changes in tropical forest dynamics and species composition under climate change.

Doctor of Philosophy / Department of Plant Pathology / Dorith Rotenberg / Frankliniella occidentalis, the western flower thrips, transmits the plant-pathogenic virus, Tomato spotted wilt virus (TSWV), through a circulative-propagative transmission strategy. The virus infects and replicates in the insect, traversing membrane barriers as it moves from the midgut to the salivary glands for subsequent inoculation of a plant host. Based on well-characterized virus-vector systems, many molecular interactions occur as the virus completes an infection cycle in the vector, and knowledge of transcriptome-wide response of thrips to TSWV has been limited. My research goals were to gain insight into i) the molecular responses that occur in thrips vectors of orthotospoviruses, ii) the role of antiviral defense in viruliferous thrips, and iii) plant transgenic-based strategies for studying thrips gene function and crop-pest control. To this end, my specific research objectives were to: 1) generate, assemble, and annotate a RNA-Seq-derived transcriptome for F. occidentalis using the thrips genome, and to quantify global gene expression in response to TSWV activity in larval, pre-pupal, and adult developmental stages, 2) conduct a time-course experiment to determine the effect(s) of challenging TSWV-exposed and non-exposed thrips with dsRNAs of F. occidentalis Dcr-2 or AGO2 by hemocoel injection, and 3) construct transgenic plants expressing a thrips-gene specific dsRNA hairpin to target a vital gene. My research has catalogued insect response to TSWV activity in thrips during development and provides candidate sequences for functional analysis of genes involved in insect development and defense. Successful silencing of the antiviral RNAi pathway in thrips revealed increased mortality and decreased offspring production in both virus-exposed and non-exposed insects. Arabidopsis plants were developed to express dsRNA of vacuolar ATP synthase (V-ATPase) and preliminary feeding bioassays to explore the effect of these transgenics on thrips fitness indicate a need for further description of thrips dsRNA uptake. In total, my research contributes new basic knowledge underpinning the complex and dynamic relationship between thrips vectors and the plant viruses they transmit.

Magister Artium - MA / This mini-thesis is concerned with histories of flower selling in Cape Town. Since the late 19th century, images and imaginings of the flower sellers in Adderley Street and to a lesser degree in other areas of the city attained an outstanding place in visualisations and descriptions of Cape Town. The flower sellers were thereby characterised in a particularly gendered, racialised and class-specific way as predominantly female, coloured and poor. This characterisation dominated to an extent that it is possible to speak of a discursive figure of the 'Cape Town flower sellers'. In tourism-related media and in personal memoirs, the 'Cape Town flower sellers' often came to represent both the city and the inhabitants of Cape Town. The images and imaginings of the 'Cape Town flower sellers' can partly be traced back to representations of 'flower girls' in fictional stories, paintings, photographs and film in Europe, particularly in Great Britain. In Cape Town, this European discourse about flower selling developed in a specific way within colonial, apartheid and post-apartheid contexts. / South Africa

Cool collabsible är ett projekt som har handlat om att skapa ett hopfällbart utomhusbord. Arbetet har utförts tillsammans med aka buna design consult. Projektet har fokuserats på att hitta en funktion, teknik och material för att sedan transformera detta till ett innovativt utomhusbord. Genom ett utförligt arbete med att definiera målgruppen skapades ramar som format ett bord till den typiska brukaren. Resultatet blev ett hopfällbart bord som hämtat sin inspiration från naturen. Ett bord som fälls upp likt en blomma som slår ut. Genom att koppla en upplevelse till en statisk produkt skapas ett mervärde till bordet, vilket medför att det kommer sticka ut från dagens marknad. / Cool collapsible is a project that involves creating an innovative collapsible outdoor table. This thesis work has been performed in collaboration with aka buna design consult in Salzburg, Austria. Aka buna design consult is a design consultant who works with different product lines, cool collapsible is an internal project where the idea is about creating a product field with different collapsible products. As an exchange student and manage to established a contact and resulted in this thesis. The project has focused on finding a function, technology or materials to then transform it into an innovative outdoor table. By extensively worked to define the target group, created a framework for a table format for the typical user. The result was a collapsible table that got its inspiration from nature. A table, that folds up like a flower blooming. By adding an experience of a static product creates a different relation to the table so that it will stand out from today's market.

The relationship between beetles and flowers is often mutually beneficial. Flowers provide not only edible rewards and favourable micro-environments, but may also be sites for mating and egg-laying activities. Even though beetles consume various parts of flowers, including pollen, and can sometimes cause considerable damage, they are in fact important pollinators of many flowers. Pollen was once considered indigestible but is actually a highly nutritious food source for many animals (including insects, birds and mammals) which use a variety of methods to digest it. Six basic methods are discussed in detail: mechanical damage, piercing and sucking, external digestion, enzymatic action, osmotic shock and pseudogermination. In this study I investigated the mechanism and efficiency of pollen digestion of two different kinds of pollen, that of maize Zea mays and sunflower Helianthus annuus, by the spotted maize beetle Astylus atromaculatus (Melyridae) an economically important pest in South Africa Histological observations were made of the gut contents and faeces of spotted maize beetles that fed on maize and sunflower. A high percentage of maize pollen grains (88%) was found to be empty and ruptured in the anterior midgut of these beetles, while sunflower pollen, although the contents were removed from most of the grains (84%), remained intact. Osmotic shock was apparently involved in digestion of maize pollen while another method, such as enzymatic action, may be used for the digestion of sunflower pollen by this beetle. Digestion efficiency of pollen, which corrects for the number of initially empty grains, was determined for the spotted maize beetle (67% for sorghum, 72% for sunflower and 74% for maize) and was found to be high in comparison to values for various mammals, birds and insects consuming pollen of other plant species. Kroon et al. (1974) proposed osmotic shock as a prerequisite for pollen digestion in honeybees and this hypothesis was accepted into the literature without question. I investigated the effect of osmotic shock on maize pollen by looking at behaviour of pollen grains under varying osmotic concentrations. Given that rainwater can sometimes cause irreversible damage to pollen grains, distilled water was used to simulate rain and sucrose solutions the stigmatic exudates of flowers. A small number of studies have focused on differences between cultivars, therefore in vitro studies were carried out subjecting maize pollen of different cultivars to different sucrose and glucose:fructose concentrations, using distilled water as a control. Results of this study indicated that maize pollen might burst in distilled water and sugar solutions of various concentrations did not decrease the amount of rupturing compared to that in water. Few studies have looked at pollen of a single plant species being digested by different animals. I compared the efficiency and mechanism of maize pollen digestion by honeybees (Apis mellifera) and spotted maize beetles. Digestive efficiency was high (80%) in beetles compared to that of bees (21 %). Maize pollen bursts early in the midgut of maize beetles but remained intact in honeybees: this suggests that osmotic shock is not as important for bees as previously suggested. / Dissertation (MSc (Entomology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

Please read the abstract in the section 00front of this document / Dissertation (MSc (Ornamental Horticulture))--University of Pretoria, 2006. / Plant Production and Soil Science / unrestricted