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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.
161

Vespas e abelhas são equivalentes quanto aos seus padrões de visitação floral ?

Klein, Ricardo Pablo January 2018 (has links)
Interações ecológicas mutualísticas são aquelas que trazem benefícios para todos os organismos envolvidos. A visitação floral fornece alimento para os animais visitantes, enquanto possibilita a reprodução sexuada em plantas. Enquanto isso, a teoria da síndrome de dispersão supõe que existem certos atributos florais (incluindo recompensas) capazes de atrair certos polinizadores e afastar outros. O declínio de abelhas tem sido reportado em todo o mundo, e encontrar espécies ecologicamente equivalentes é crucial para a preservação da biodiversidade. Vespas possuem funções ecológicas semelhantes às abelhas apesar de não dependerem exclusivamente de pólen e néctar para sobreviver. O objetivo deste projeto de pesquisa foi avaliar as diferenças da visitação floral entre abelhas/plantas e vespas/plantas. O primeiro capítulo possui uma abordagem de redes de interação. O segundo capítulo apresenta uma abordagem multivariada onde avaliamos as diferenças entre as plantas de acordo com os himenópteros visitantes florais. Nós realizamos as coletas em unidades de conservação do município de Porto Alegre. Em cada área de estudo, foram definidas transecções em três ambientes distintos: campo, mata e borda entre estes. As amostragens em cada transecção ocorreram entre horários de 9h e 17h. Durante este período, foram observadas as plantas em floração, entre 20 cm a 4 m de altura, e seus himenópteros visitantes florais coletados com o auxílio de rede entomológica durante 10 minutos em cada planta. As métricas de rede foram calculadas do programa R com o pacote Bipartite. Vespas e abelhas são visitantes florais distintos quanto a seus padrões de redes de interação. Vespas seriam capazes de manter apenas a metade da diversidade vegetal através da polinização após eventos hipotéticos de extinção de abelhas. Através da abordagem multivariada, as plantas visitadas por vespas e por abelhas não formaram grupos distintos. Quanto maior a abertura da corola da flor, menor é a visitação floral de vespas. Concluímos que vespas podem ser polinizadores auxiliares para a manutenção da diversidade vegetal, apesar de serem capazes de manter menor diversidade vegetal em cenários de extinção de abelhas. Além disso, os atributos florais de vespas e abelhas não são diferentes entre si, apontando para o fato de que vespas podem ser polinizadores de um maior número de plantas do que o previsto. / Mutualistic ecological interactions are those that bring benefits to all involved organisms. Floral visitation provides food for visiting animals, while allowing sexual reproduction in plants. Meanwhile, the dispersion syndrome theory assumes that there are certain floral attributes (including rewards) that can attract certain pollinators and drive away others. The decline of bees has been reported worldwide and finding ecologically equivalent species is crucial to the preservation of biodiversity. Wasps have ecological functions like bees although they do not depend exclusively on pollen and nectar to survive. The objective of this research was to evaluate the differences in floral visitation between bees/plants and wasps/plants. The first chapter has an interaction network approach. The second chapter presents a multivariate approach where we evaluate differences between plants according to the floral visiting wasps and bees. We carried out sampling in conservation units of the municipality of Porto Alegre. In each study area, transects were defined in three distinct environments: grassland, forest and edges between them. Sampling at each transection occurred between 9 and 17 h. During this period, flowering plants from 20 cm to 4 m tall were observed, and their floral visiting Hymenoptera collected with the aid of an entomological net for 10 min on each plant. The network metrics were calculated with R software with the Bipartite package. Wasps and bees are distinctive floral visitors given their different patterns of interaction networks. Wasps maintain half of the plant diversity after the hypothetical events of bee extinction. Under a multivariate approach, plants visited by wasps and bees did not form distinct groups. The widder the corolla of the flower, the less is the floral visitation of wasps. We conclude that wasps can be secondary pollinators for the maintenance of plant diversity, although they are able to maintain lower plant diversity in bee’s extinction scenarios. In addition, the floral attributes of wasps and bees are not different from each other, pointing to the fact that wasps may be pollinators of a larger number of plants than predicted.
162

Idosos e Florais de Bach: em busca do restabelecimento da auto-estima / Elderly and Bach Flowers Remedies: in search of restoring self-esteem

Cozin, Sheila Katia 30 September 2009 (has links)
A preocupação em compreender o indivíduo de forma holística está gradativamente aumentando na área da saúde. Neste cenário os Florais de Bach consolidam-se, buscando suprir as necessidades emocionais dos indivíduos, incluindo a auto-estima, degradada em muitos idosos pela falta de auto-confiança e auto-respeito que vivenciam. Acreditando que as essências florais são capazes de estimular comportamentos e atitudes positivas e aumentar a percepção e compreensão dos sentimentos, optou-se por avaliar a efetividade dos Florais de Bach na melhora da auto-estima de idosos. Desenvolveu-se um estudo experimental, tipo ensaio clínico, triplo-cego, com idosos atendidos em dois ambulatórios de geriatria de São Paulo. Para avaliação da auto-estima utilizou-se o instrumento de Dela Coleta e para caracterização dos idosos uma anamnese de dados sócio-culturais-demográficos. De Abril/2008 a Julho/2009 abordou-se para avaliação da auto-estima 665 idosos. Desses, 15,9% (106) apresentou escore de auto-estima referente à baixa/média auto-estima, porém somente 80 preencheram também os outros critérios de inclusão do estudo. Ao fim, com as desistências, obteve-se 67 idosos, 35 alocados no Grupo Experimental e 32 no Grupo Placebo. Estes idosos participaram de três atendimentos em Terapia Floral, um a cada 45 dias nos quais se avaliou a auto-estima e se registrou os relatos de evolução dos problemas e sentimentos relacionados à auto-estima. Em todos os atendimentos os idosos escolheram seis Florais de Bach através da técnica de escolha das fotos das flores correspondentes. A cada idoso forneceu-se dois frascos com solução base, sendo que aos do Grupo Experimental acrescentou-se as essência florais escolhidas. Somente no último atendimento os idosos souberam dos significados das flores escolhidas durante o estudo, e todos os participantes receberam mais dois frascos, agora com os Florais escolhidos, permitindo o contato de todos os participantes ao tratamento. Para a verificação estatística da efetividade dos Florais sobre a auto-estima realizou-se o Teste de Tukey-HSD, observando-se que não houve diferença estatística entre os Grupos Experimental e Placebo. Houve melhora da auto-estima em ambos os grupos de estudo, porém no Grupo Experimental observou-se tendência progressiva de melhora enquanto que no Grupo Controle a auto-estima sofreu melhora imediata e manteve-se inalterada. Acredita-se que o relacionamento terapêutico estabelecido durante os atendimentos foi capaz de melhorar a auto-estima dos idosos do Grupo Placebo, porém somente os Florais forneceram subsídios ao individuo trabalhar sua auto-estima efetivamente. Reforçando isto, somente no Grupo Experimental observou-se evolução positiva do bem-estar geral relatado pelos idosos. Sugere-se que o tempo de exposição ao tratamento foi muito curto para observação da uma melhora maior no Grupo Experimental e o instrumento utilizado não foi o mais adequado para esta população, visto que não abrangia questões especificas da auto-estima em idosos. Percebeu-se que a Flor de Bach mais relevante foi a Red Chestnut, a única Flor que nos três atendimentos esteve entre as preferidas dos idosos de ambos os grupos. Esta flor evidencia duas das principais queixas dos idosos: o excesso de preocupação, principalmente com os filhos, netos e com a condição financeira / The concern in understanding the individual in a holistic way is gradually increasing in the health field. In this scenario, the Bach Flower Remedies consolidate in an attempt to supply the emotional needs of individuals, including the self-esteem, degraded in many older people due to the lack of self-confidence and self-respect that they experience. Believing that flower essences are able to stimulate positive behaviors and attitudes and increase awareness and comprehension of feelings, we decided to evaluate the effectiveness of the Bach Flower Remedies in the improvement of the self-esteem of older people. We developed an experimental study, clinical trial, triple-blind, elderly assisted by two geriatric clinics in Sao Paulo. To assess self-esteem it was used the instrument of Dela Coleta and the characterization of an old history of socio-cultural and demographic. From April/2008 to July/2009 addressed to assessing self-esteem 665 people. Of these, 15.9% (106) had scores of self-esteem on the low / medium self-esteem, but only 80 also met the other criteria for inclusion in the study. The end, with the dropouts, we got 67 seniors, 35 allocated in the experimental group and 32 in the placebo group. These seniors participated in three appointments to Flower Therapy, one every 45 days during which we evaluated the self-esteem and registered reports of developments on issues related to feelings and self-esteem. At every appointment the elderly chose six Bach Flowers using the technique of choice of photos matching flowers. For every elderly were provided two bottles of base solution, and to the experimental group was added to the flower essence chosen. Only at the last treatment, the elderly had known the meaning of the flowers chosen for the study and all participants received two more bottles, now with the flowers chosen, allowing contact of all participants to treatment. For statistical verification of the effectiveness of Flowers on self-esteem was held to the Tukey-HSD, resulting in that there was no statistical difference between the Experimental and Placebo Groups. There was improvement in self-esteem in both study groups, but in the experimental group there was a trend of gradual improvement while in the placebo group self-esteem has improved immediately and remained unchanged. It is believed that the therapeutic relationship established during the sessions was able to improve self-esteem of older people in the placebo group, but only Bach flowers provided subsidies to improve individuals self-esteem effectively. Reinforcing this, only in the experimental group it showed positive development of well-being reported by the elderly. It is suggested that the exposure time to treatment was too short for the observation of a greater improvement in the experimental group and the instrument used was not the most appropriate for this population, as they did not cover specific issues of self-esteem in the elderly. It was noticed that the more relevant Bach flower was Red Chestnut, the only one that in all appointments was among the favorite flowers of the elderly in both groups. This flower shows the principal complaints of the elderly: over-concern, especially with the children, grandchildren and the financial condition
163

Phylogeny, molecular dating and floral evolution of Magnoliidae (Angiospermae) / Phylogénie, datation moléculaire et évolution florale des Magnoliidae (Angiospermes)

Massoni, Julien 11 April 2014 (has links)
Les relations de parentés profondes au sein des Angiospermes ont été longtemps incertaines. A la fin des années 90, les études phylogénétiques à grande échelle ont contribué à l’obtention de l’arbre actuel des Plantes à fleurs, dans lequel Eudicotylédones, Monocotylédones et Magnoliidae forment les trois plus grands clades. Contrairement aux Monocotylédones et aux Eudicotylédones, la monophylie des Magnoliidae (Canellales, Laurales, Magnoliales et Piperales) n’a été soutenue que plus récemment. Les Magnoliidae contiennent actuellement 20 familles et environ 10 000 espèces majoritairement présentes sous les tropiques. Avant cette thèse, de nombreuses parties de ce groupe avaient été étudiées en détail mais l’histoire évolutive du groupe dans son ensemble était encore mal connue. Le premier chapitre est une étude phylogénétique des relations entre les familles et les ordres de Magnoliidae. Pour réaliser cette étude, j’ai échantillonné 199 espèces du groupe et 12 marqueurs moléculaires issus des trois génomes. J’ai ensuite mené des analyses phylogénétiques avec les méthodes de parcimonie, d’inférence bayésienne et de maximum de vraisemblance. Les résultats confirment avec un plus fort soutien la présence de deux clades dans ce groupe : Canellales + Piperales et Laurales + Magnoliales. De plus, les relations entre les 20 familles sont généralement bien soutenues, les Lactoridaceae et les Hydnoraceae étant incluses dans les Aristolochiaceae (Piperales). Dans le second chapitre, j’ai révisé l’âge et la position de 10 fossiles identifiés comme appartenant aux Magnoliidae. Le but de cette étude était de fournir de nouveaux points de calibration fiables afin de conduire de nouvelles analyses de datation moléculaire. Parmi les nombreux fossiles du groupe, nous avons choisi ces espèces car elles avaient été placées phylogénétiquement par des études antérieures. Le schéma de calibration résultant de ce travail inclut six contraintes fiables d’âges minimum. Le troisième chapitre est une étude de datation moléculaire utilisant ce schéma de calibration et le même jeu de données moléculaires que le chapitre 1. Les résultats tendent à repousser l’âge des Magnoliidae (127.1-198.9 Ma), et des quatre ordres Canellales (126.3-141.0 Ma), Piperales (88.2-157.7 Ma), Laurales (111.8-165.6 Ma) et Magnoliales (115.0-164.2 Ma). Dans ce même chapitre, j’ai également étudié le mode de diversification du groupe. Les variations importantes du nombre d’espèces entre les différentes parties de l’arbre s’expliquent le mieux par des modèles de diversification incluant 6 à 14 transition du taux net de diversification. Enfin, dans le dernier chapitre de la thèse, j’ai retracé l’histoire évolutive de 26 caractères floraux pour reconstruire les fleurs ancestrales de nœuds-clés des Magnoliidae. Pour ce faire, j’ai tiré parti de la phylogénie du premier chapitre et utilisé les mêmes espèces dans ma matrice morphologique. Les résultats montrent que l’ancêtre commun le plus récent des Magnoliidae présentait des fleurs bisexuées et actinomorphes avec un périanthe différencié de deux cycles trimères à tépales libres et probablement trois étamines libres. Ce travail de thèse apporte des résultats importants sur l’évolution des Magnoliidae et soulève de nombreuses questions telles que l’impact des crises géologiques sur la diversification du groupe ou l’influence des pollinisateurs et de l’environnement sur l’évolution de la morphologie florale. / Deep phylogenetic relationships in the angiosperms had long been uncertain. However, by the end of the 1990s, large-scale studies contributed to the current well resolved picture of the tree of flowering plants, in which eudicots, monocots, and magnoliids are the three largest clades. Whereas monocots and eudicots have been recognized since the very first phylogenetic analyses, the monophyly of magnoliids (Canellales, Laurales, Magnoliales, and Piperales) is a more recent result. Magnoliidae, as now circumscribed, consist of 20 families and ca. 10,000 species mostly distributed in the tropics. Before the present thesis, several parts of the magnoliid tree had been well studied, but little was known about the evolutionary history of Magnoliidae as a whole. The first chapter of this thesis is a phylogenetic study conducted to clarify the relationships among families and orders of Magnoliidae. To do so, I sampled 199 species of Magnoliidae and 12 molecular markers from the three genomes and conducted phylogenetic analyses using parsimony, maximum likelihood, and Bayesian methods. The results confirm, with a greater level of support, two clades in Magnoliidae: Canellale + Piperales, and Laurales + Magnoliales. In addition, the relationships among the 20 families are generally well supported, and Lactoridaceae and Hydnoraceae are nested within Aristolochiaceae (Piperales). In the second chapter, the ages and phylogenetic positions of 10 fossils attributed to Magnoliidae were reviewed in detail. The goal of this study was to provide new reliable calibration points in order to conduct molecular dating analyses. These fossils were selected from the rich fossil record of the group because of their previous inclusion in phylogenetic analyses with extant taxa. The resulting calibration scheme provides six solid, internal minimum age constraints. The third chapter includes molecular dating analyses using the present calibration scheme and the same molecular dataset of Chapter 1. This study tends to push back in time the ages of the crown nodes of Magnoliidae (127.1-198.9 Ma), and of the four orders, Canellales (126.3-141.0 Ma), Piperales (88.2-157.7 Ma), Laurales (111.8-165.6 Ma), and Magnoliales (115.0-164.2 Ma). In the same chapter, I investigated the mode of diversification in the group. The strongly imbalanced distribution of species appears to be best explained by models of diversification with 6 to 14 diversification rate shifts. Finally, in the last chapter, I traced the evolution of 26 floral characters to reconstruct the ancestral flowers in key nodes of Magnoliidae. I used the phylogeny of Chapter 1 and an exemplar approach. Our results show that the most recent common ancestor of all Magnoliidae was a tree bearing actinomorphic, bisexual flowers with a differentiated perianth of two alternate, trimerous whorls of free perianth parts (outer and inner tepals) and probably three free stamens. This work provides key results on the evolution of Magnoliidae and raises several new questions such as the impact of geological crises on diversification of the group or the influence of pollinators and the environment on the evolution of floral morphology.
164

Abelhas visitantes florais de Vernonia polyanthes Less (Asteraceae), em Valen?a-RJ / Floral visitor bees of Vernonia polyanthes Less (Asteraceae) in Valen?a-RJ

ALVES, Luis Henrique Soares 26 February 2010 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-10T18:35:49Z No. of bitstreams: 1 2010 - Luis Henrique Soares Alves.pdf: 520241 bytes, checksum: 165a3d93ee175bf9fd585ae8e76ab2da (MD5) / Made available in DSpace on 2017-04-10T18:35:49Z (GMT). No. of bitstreams: 1 2010 - Luis Henrique Soares Alves.pdf: 520241 bytes, checksum: 165a3d93ee175bf9fd585ae8e76ab2da (MD5) Previous issue date: 2010-02-26 / CAPES / Vernonia polyanthes Less. popularly known as ?assa-peixe?, ?assa-peixe branco? or ?cambar??, belongs to the ?Asteraceae? family and it?s very used by the popular medicine on the treatment of coughs, bronchitis, bruises, hemorrhoids, colds and uterine infections. V. polyanthes is very visited by many species of bees, principally by native ones, that look for food resources. Besides the native bees that are responsible for even 90% of pollination of the native vegetables, Apis mellifera looks for food resources in those vegetables too. This specie, was introduced in Brazil during the colonial period. We don?t known yet about the consequences of the introduction of this specie over the native bees communities, once there is little work accomplished with that purpose. This work has an objective of knowing the principal flora visitors of V. polyanthes and the interactions between the bees communities. The work was done in Valen?a municipal district-RJ, in an area with 15 beehives of A. mellifera. Four collections were accomplished with entomological net with 10 minutes of duration in each hour from 08 a.m to 04 p.m, once a week from June to August 2009. It were collected 771 bees from 03 families and 22 species. The more abundant species were A. mellifera, T. spinipes and S. quadripunctata. The social bees represented 98% of the total in relation to lonely ones with only 2%. From the 22 species, A. mellifera and T. spinipes were dominant in the exploration of resources over the other bee species. A great similarity about the exploration of food resources happened between A. mellifera, T. spinipes and S. quadripunctata, possibly for being happening a competition between those species. The low diversity of bees could be influenced by abundant quantity of A.mellifera. This work has found one of the biggest number of melipon?neos species collected in the state of Rio de Janeiro. / Vernonia polyanthes Less. conhecida popularmente por assa-peixe, assa-peixe-branco, cambar?, pertence ? fam?lia Asteraceae e ? muito utilizada pela medicina popular no tratamento de tosses, bronquite, contus?es, hemorr?idas, resfriados e infec??es uterinas. V. polyanthes ? muito visitada por v?rias esp?cies de abelhas, principalmente por abelhas nativas, que buscam recursos alimentares. Al?m das abelhas nativas, que s?o respons?veis por at? 90% da poliniza??o dos vegetais nativos, APIS MELLIFERA BUSCA RECURSOS ALIMENTARES NESSE VEGETAL. Essa esp?cie foi introduzida no Brasil durante o per?odo colonial e ainda n?o se sabe as conseq??ncias da introdu??o dessa esp?cie sobre as comunidades de abelhas nativas, uma vez que s?o poucos os trabalhos realizados com essa finalidade. Esse trabalho possui como objetivo conhecer os principais visitantes florais de V. polyanthes e as intera??es entre as comunidades de abelhas. O trabalho foi realizado no munic?pio de Valen?a-RJ, em uma ?rea com 15 colm?ias de A. mellifera. Foram realizadas quatro coletas com rede entomol?gica com 10 minutos de dura??o em cada hora, das 08 ?s 16 horas uma vez por semana, entre junho e agosto de 2009. Foram coletadas 771 abelhas pertencentes a tr?s fam?lias e 22 esp?cies. As esp?cies mais abundantes foram A. mellifera, T, spinipes e S. quadripunctata. As abelhas sociais representaram 98% do total em rela??o ?s abelhas solit?rias com 2%. Das 22 esp?cies, A. mellifera e T. spinipes foram dominantes na explora??o de recursos sobre as demais esp?cies de abelhas. Ocorreu uma grande similaridade na explora??o de recursos alimentares entre A. mellifera, T. spinipes e S. quadripunctata, possivelmente por estar ocorrendo uma poss?vel competi??o entre essas esp?cies. A baixa diversidade de abelhas pode ter sido influenciada pela abund?ncia de A. mellifera. Esse trabalho encontrou um dos maiores n?meros de esp?cies de melipon?neos coletadas no estado do Rio de Janeiro.
165

A arte japonesa e a Ikebana na produção de Toshiro Kawase / The Japanese art and the Ikebana in Toshiro Kawases production

Freire, Adriana Bomeny 22 August 2014 (has links)
Esta pesquisa visou possibilitar o conhecimento da Ikebana como uma manifestação estética significativa, integrante da história da arte japonesa e que vem se disseminando pelo mundo. Para compreensão da sua estética, será demonstrado como exemplo o trabalho do artista contemporâneo Toshiro Kawase, o estudo do Zen e suas características. Toshiro Kawase é um artista especializado na arte da Ikebana, e suas obras resultaram em dois livros de âmbito internacional: Inspired Flower Arrangements (1990) e The Book of Ikebana (2000). A arte japonesa é baseada nos sentimentos e na simplicidade de expressão, que motivaram este povo a utilizar a natureza como suporte para executar memoráveis obras de arte. Ao longo da história, no oriente e no ocidente da mesma forma, a beleza das flores adicionou graça e charme na vida das pessoas. A pesquisa analisa a arte japonesa e sua ligação inseparável com a religião, abordando principalmente os aspectos do sagrado, o conceito do belo e a real função do artista de Ikebana. / This research intends to show Ikebana by being an esthetic manifestation of art, that been walking side by side with all stages of Art History. To understand the esthetic of Ikebana, will be demonstrated by example, the contemporary artist Toshiro Kawase, the Zen study and its characteristics. Toshiro Kawase is an artist specialized in Ikebanas Art, and his production inspired two international books: Inspired Flower Arrangements (1990) and The Book of Ikebana (2000). The Japanese art is based on emotions and expression simplicity that motivated this people to use the nature like a support to execute memorable works of art. In all parts of history of the art, in occident and in the orient at the same way, the beauty of flowers added grace and charm in peoples life. The question is: Why do Ikebanas art appeared only in Japan or related to Japanese? This research, analyses the Japanese art and its unbreakable link with religiosity, often the sacred aspect, the definition of beauty and the real functionality of the artist. This research also presents aspects of the principal objective of art, and how to do its communication purposing the perpetuation of his human experiences.
166

Borya mirabilis steps in the recovery of a critically endangered Australian native plant

Reiter, Noushka Hedy, noushka.reiter@dse.vic.gov.au January 2009 (has links)
Borya mirabilis is one of the world's most critically endangered plants. The research in this thesis has illuminated key aspects of: its reproductive biology; interspecies and intraspecies molecular relationships, mycorrhizal status, tissue culture potential and disease threats. Each of these aspects has fundamental management implications for the active management of B. mirabilis. Floral observations of B. mirabilis and related species affirmed the uniqueness of the Boryaceae amongst the Asparagales. B. mirabilis had an unusually high number of floral abnormalities compared with other species of Borya observed. B. mirabilis is fly-pollinated. Pollen of Borya species showed little difference in the characteristics of mature pollen between species, with viable pollen being prolate and unicolpate with a single colpa-style aperture and a unique patterning of the pila. The structural immaturity of B. mirabilis pollen correlated with evidence from pollen growth experiments, where B. mirabilis pollen had extremely low germination rates, with those grains that did germinate being slow to do so and with slow-growing pollen tubes compared to those of fertile Borya species. Examination of the ovules of B. mirabilis showed that morphologically they were viable compared to viable Borya species. The field population of B. mirabilis was crossed, with one seed produced (the first recorded seed for th is species). Cross-pollination using the pollen of the closely related B. constricta and B. sphaerocephala with B. mirabilis ovules proved unsuccessful. Examination of the chromosome number of B. mirabilis showed that it had approximately 66 chromosomes and is probably hexaploid, relative to the diploid number of 26 in B. constricta. This may explain its low fertility. Interspecies and intraspecies relationships of the Boryaceae and Borya mirabilis were investigated using sequences of chloroplast and nuclear DNA. The closest similarities to B. mirabilis were B. constricta and B. sphaerocephala. B. mirabilis may have emerged from alloploidy of these species in the past. Because of the consistent similarities of B. mirabilis and B. constricta chloroplast sequences, it is proposed that both shared a common ancestor with a chromosome number of 2n=22. A malfunction n meiosis may have resulted in ovules with 2n=44. The high similarity of the nuclear ribosomal ITS region DNA suggests that the nuclear DNA was derived from B. sphaerocephela. B. mirabilis may be an allopolyploid, from fertilisation of a diploid ovule of B. constricta with haploid pollen of B. sphaerocephala, resulting in a reproductively isolated polyploidy of low fertility. The wild population of B. mirabilis was determined to have a small amount of genetic variation. The genetic variation in the field population w as not fully reflected in the ex-situ population. An effective means of micro-propagation of B. nitida for use in B. mirabilis has been established, providing an effective means of mass production of the species. The research has determined: a suitable explant (shoot tips) for regeneration; an effective means of reducing contamination in tissue culture (PPM); what medium is required to micro-propagate the species (LMHM); an appropriate gelling agent (Phytagel); and a practical method for inducing roots on the shoots grown in tissue culture. B. mirabilis has been established as mycorrhizal. The predominant mycorrhizal association is a nodular arbuscular mycorrhiza, present in the form of coils in root nodules over wetter months and as spores in these nodules over dryer months. A significant increase in the health of the ex-situ population of B. mirabilis was recorded after addition of soil containing fine roots of the wild population. Of the plants associated with the wild population, Callitris rhomboidea had the most morphologically similar vesicular arbuscular mycorrhizal relationship. But molecular identification was not achieved due to recalcitrance of DNA in PCR attempts. Potential translocation sites for some of the ex-situ population of B. mirabilis were examined for Phytophthora infestation. Reid's Lookout and Mackey's Peak were infected with P. cinnamomi. Vegetation at Mackey's Peak displayed characteristic infection symptoms, resulted in isolates of P. cinnamomi from baiting and would directly receive runoff from both the walking track and the existing infested B .mirabilis site. At the Reid's Lookout site, both walking track and proposed translocation site were infested with P. cinnamomi, yet did not display the associated symptoms in the vegetation. The Pine Plantation translocation site was uninfected at the level of sampling undertaken. Its vegetation did not display any characteristic infection symptoms and was not isolated when soil samples were baited. It was therefore chosen for translocation and so far the plants are healthy and actively growing. This research has provided critical knowledge to aid the recovery team in its current and future endeavours to manage this species and bring it back from the brink of extinction.
167

Environmental factors controlling the distribution of forest plants with special reference to floral mixture in the boreo-nemoral ecotone, Hokkaido Island / 森林植物の分布と環境要因、特に北海道の森林フロラの混在様式に関する生態学的研究

Uemura, Shigeru 30 June 1992 (has links)
Effects of climatic factors on the plant distribution were examined by means of direct gradient analysis, and the relationship of forest flora, life form and phytogeographical distribution was examined. Subsequently, leaf phenology of forest plants were analyzed to evaluate the adaptive significance in relation to the environments in forest understory. In the boreo-nemoral forest ecotone, Hokkaido Island, northern Japan, co-ccurrence of northern and southern plants in a certain forest site is more notable in the understory than in the crown, and this dates back to the late-uaternary period, where the decrease in temperature associated with the glacial period forced the understory flora to adapt their life form or leaf habits to snowcover and light conditions of the interior forests. / Hokkaido University (北海道大学) / 博士 / 環境科学
168

Analyse fonctionnelle de la protéine WSCP chez Arabidopsis thaliana

Boex-Fontvieille, Edouard 17 September 2010 (has links) (PDF)
Les protéines WSCP (Water-soluble Chlorophyll binding Proteins) de classe II sont des protéines solubles capables de fixer la chlorophylle et ses dérivés chez les Brassicaceae. Ces protéines font partie de la famille des inhibiteurs de protéases et elles présentent la particularité d'être induites en conditions de stress abiotiques à la lumière. Leurs fonctions in planta sont à ce jour très peu documentées. Cette thèse présente l'étude de la fonction physiologique d'une WSCP chez la plante modèle Arabidopsis thaliana. Nous avons montré dans un premier temps que la protéine WSCP n'est pas induite en conditions de stress pendant la photomorphogénèse. En revanche, elle est exprimée dans les plantules à l'obscurité (étiolées) et dans le tissu de transmission des fleurs, lieu de passage des tubes polliniques. Dans la fleur, nous avons mis en évidence la régulation de WSCP par les facteurs de transcriptions HEC et NTT impliqués dans le développement floral. Par une approche de génique inverse, nous avons montré un rôle de WSCP dans le contrôle de la mort cellulaire du tissu de transmission. En conséquence, la progression des tubes polliniques est altérée et la mort cellulaire non spécifique influence le développement des graines. Chez les plantules étiolées, le transcrit WSCP est exprimé au niveau de la crosse apicale, structure dont la fonction est de protéger les plantules au cours de l'émergence hors du sol. De manière intéressante, les facteurs NTT et HEC sont également exprimés dans les plantules étiolées mais régulent l'expression du gène WSCP de façon différente. De plus, la protéine WSCP s'accumule en présence de l'hormone de stress éthylène dans la crosse apicale et l'activité du promoteur du gène WSCP augmente en conditions de stress mécaniques. Prises ensembles, ces expériences laissent présager d'un rôle protecteur de la protéine WSCP au cours de la skotomorphogénèse.
169

Plant-Herbivore Interactions and Evolutionary Potential of Natural Arabidopsis lyrata Populations

Puentes, Adriana January 2012 (has links)
In this thesis, I combined field, greenhouse and common-garden experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions and the genetic architecture of fitness-related traits in the insect-pollinated, self-incompatible, perennial herb Arabidopsis lyrata. More specifically, I examined (1) whether damage to leaves and inflorescences affects plant fitness non-additively, (2) whether trichome production is associated with a cost in terms of reduced tolerance to leaf and inflorescence damage, (3) whether young plant resistance to a specialist insect herbivore varies among populations, and (4) whether the evolution of flowering time, floral display and rosette size is constrained by lack of genetic variation or by genetic correlations among traits. A two-year field experiment in a Swedish population showed that damage to rosette leaves and to inflorescences can affect both current and future plant performance of A. lyrata, and that effects on some fitness components are non-additive. A two-year field experiment in another Swedish population indicated that trichome-producing plants are not less tolerant than glabrous plants to leaf and inflorescence damage. In a greenhouse experiment, acceptability of young plants (5-6 weeks old) to ovipositing females and damage received by Plutella xylostella larvae varied considerably among twelve A. lyrata populations. Both oviposition and leaf damage were positively correlated with rosette size, but trichome density in the trichome-producing morph was apparently too low at this developmental stage to influence resistance to P. xylostella. In a common-garden experiment, flowering time, floral display and rosette size varied among four Scandinavian A. lyrata populations, and displayed significant additive genetic variation in some populations. Yet, strong genetic correlations between flowering start and number of flowers, and between petal length and petal width suggest that these traits may not evolve independently. Taken together, the results indicate the need to consider possible long-term and non-additive effects of herbivore damage to different plant parts, that there is no trade-off between trichome production and tolerance to herbivory, that the importance of morphological defenses against herbivory may change through plant ontogeny, and that considerable genetic variation for traits such as flowering time and floral display can be maintained in natural plant populations.
170

Toward functional characterization of <i>Triticum aestivum WFCA</i>-coding sequences

Hoffman, Travis L. 06 July 2012
<p>Flowering is a critical step in the plant life cycle. If flowering occurs too early or too late, seed production suffers. Flowering is regulated through numerous flowering repressors. As long as these repressors persist, the plant will remain in a vegetative growth stage. Some plants possess two separate genetic pathways, the autonomous pathway and the vernalization pathway, that promote the transition to flowering through stable downregulation of flowering repressors. Once the plant achieves floral competence, it will flower under inductive environmental conditions.</p> <p>In <i>Arabidopsis</i>, <i>FCA</i> is a key autonomous pathway gene, acting with <i>FY</i> to promote the floral transition. Recently, gene sequences resembling <i>FCA</i> were cloned from hexaploid wheat (<i>Triticum aestivum</i>) and designated as <i>WFCA</i>. WFCA shows numerous similarities to the FCA peptide, especially regarding three key regions: two RNA Recognition Motifs and the WW domain. This study seeks to determine if <i>WFCA</i> genes function similar to <i>FCA</i> by determining if they are able to complement the <i>fca-1</i> mutant of <i>Arabidopsis thaliana</i>.</p> <p>T1 progeny from an <i>Arabidopsis fca-1</i> plant transformed with <i>WFCA</i> were grown without vernalization and assayed for the final leaf number (FLN). The late flowering <i>fca-1</i> control plants bolted with an average FLN of 14.8 while the T1 population had an average FLN of 14.3. Although the numerical difference is slight, the results are statistically significant, and suggest that <i>WFCA</i> genes may have some degree of flowering promotion activity in <i>Arabidopsis</i>. The lack of strong complementation may be due to divergence of the <i>WFCA</i> genes from their <i>Arabidopsis</i> counterparts. With increasing evidence for divergence in flowering promotion between monocot and dicot species, the development of a robust monocot model system appears to be critical to provide a good framework to assist studies of the particular nuances of the monocot flowering process.</p>

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