23 research outputs found

    Análise morfoanatômica comparativa da folha de Bauhinia forficata (Link) e B.variegata (Linn). (Leguminosae:Caesalpinioideae)

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    Orientadora: Cleusa BonaMonografia (Bacharelado) - Universidade Federal do Paraná. Setor de Ciencias Biológicas. Curso de Graduaçao em Ciencias BiológicasResumo : Análise morfoanatômica comparativa da folha de Bauhinia forficata (Link) e B. variegata (Linn). (Leguminosae: Caesalpinioideae). Este trabalho foi desenvolvido por indicação da Farmacopéia Brasileira, com o propósito de subsidiar o controle de qualidade das espécies medicinais. Foram analisadas e descritas de forma comparativa a morfologia, a venação foliar e a estrutura anatômica das folhas de Bauhinia forficata (Link) e B. variegata (Linn). O material botânico das espécies foi coletado no Campus Centro Politécnico da Universidade Federal do Paraná, Curitiba, Paraná, Brasil e em jardins e terrenos baldios da mesma cidade. As amostras de limbo, pecíolo e pulvino foram fixadas em FAA 50 e conservadas em álcool 70, sendo parte do material processado para inclusão em historresina. O seccionamento do material foi feito em micrótomo de rotação ou a mão livre e as lâminas foram montadas de forma permanente ou semipermanente. Foram realizadas análises em microscopia fotônica e eletrônica de varredura. As espécies B. forficata e B. variegata apresentam várias características distintas. A folha de B. forficata é alongada, com lobos unidos em torno da metade do limbo, ápices agudos, superfície adaxial lisa e mucro entre os lobos. Enquanto que, B. variegata possui folha mais larga que longa, com lobos unidos na porção terminal do limbo e ápices obtusos. Nos pulvinos de B. variegata ocorrem camadas de colênquima, ausentes em B. forficata. O formato e a bainha de fibras dos pecíolos, em secção transversal, são distintos entre as espécies, assim como a distribuição dos estômatos e tricomas no limbo e a forma do bordo. B. variegata possui maior quantidade de idioblastos com drusas e compostos fenólicos. As características morfológicas e anatômicas de B. forficata e B. variegata contribuem para a identificação e diferenciação das espécies, sendo importantes para o controle de qualidade do material destinado à pesquisa e a industria farmacêutica

    Deep in the Jelly: Histochemical and Functional Aspects of Mucilage-Secreting Floral Colleters in the Orchids Elleanthus brasiliensis and E. crinipes

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    Colleters are trichomes or emergencies that produce a sticky exudate consisting of a mixture of mucilage, lipids, terpenes, and phenolic compounds. Colleters occur in at least 60 families of angiosperms; however, reports of them are scarce for the Orchidaceae. Elleanthus brasiliensis is distinguished by the presence of an abundant gelatinous secretion that covers almost all of its inflorescences. We aimed to describe the histology of colleters in inflorescences of E. brasiliensis and Elleanthus crinipes, and to analyze the chemical composition of their secretion to better understand the functions of these secretory structures. Due to the low frequency of colleters and lack of visible secretion in E. crinipes, histochemical tests and chemical analyses were not performed for this species. Colleters are of a brush type and their secretion has, at the same time, hydrophilic and lipophilic components. Histochemical tests further revealed the presence of pectin, mucilage, lipids, terpenes, phenolic compounds, and proteins. The GC-MS analysis confirmed the presence of γ-sitosterol and palmitic, linoleic, and stearic acids in the secretion of E. brasiliensis. Infrared analysis indicated the possible presence of polysaccharides in the secretion. The occurrence of colleters in both species studied and in other orchids described in the literature suggests that these structures are common in the inflorescences of tropical orchids. In these environments, the hydrated polysaccharides in the secretion form a dense matrix that can act as a physical barrier, and terpenes may help to protect against herbivores and pathogenic microorganisms. This information broadens our knowledge of the morphological and chemical diversity of the secretions produced by orchid colleters

    Trichomes related to an unusual method of water retention and protection of the stem apex in an arid zone perennial species

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    It is well known that trichomes protect plant organs, and several studies have investigated their role in the adaptation of plants to harsh environments. Recent studies have shown that the production of hydrophilic substances by glandular trichomes and the deposition of this secretion on young organs may facilitate water retention, thus preventing desiccation and favouring organ growth until the plant develops other protective mechanisms. Lychnophora diamantinana is a species endemic to the Brazilian 'campos rupestres' (rocky fields), a region characterized by intense solar radiation and water deficits. This study sought to investigate trichomes and the origin of the substances observed on the stem apices of L. diamantinana. Samples of stem apices, young and expanded leaves were studied using standard techniques, including light microscopy and scanning and transmission electron microscopy. Histochemical tests were used to identify the major groups of metabolites present in the trichomes and the hyaline material deposited on the apices. Non-glandular trichomes and glandular trichomes were observed. The material deposited on the stem apices was hyaline, highly hydrophilic and viscous. This hyaline material primarily consists of carbohydrates that result from the partial degradation of the cell wall of uniseriate trichomes. This degradation occurs at the same time that glandular trichomes secrete terpenoids, phenolic compounds and proteins. These results suggest that the non-glandular trichomes on the leaves of L. diamantinana help protect the young organ, particularly against desiccation, by deposition of highly hydrated substances on the apices. Furthermore, the secretion of glandular trichomes probably repels herbivore and pathogen attacks7CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302776/2010- 9; 302657/2011-82010/51454-3; 2010/02085-

    Deep in the Jelly: Histochemical and Functional Aspects of Mucilage-Secreting Floral Colleters in the Orchids Elleanthus brasiliensis and E. crinipes

    Get PDF
    Colleters are trichomes or emergencies that produce a sticky exudate consisting of a mixture of mucilage, lipids, terpenes, and phenolic compounds. Colleters occur in at least 60 families of angiosperms; however, reports of them are scarce for the Orchidaceae. Elleanthus brasiliensis is distinguished by the presence of an abundant gelatinous secretion that covers almost all of its inflorescences. We aimed to describe the histology of colleters in inflorescences of E. brasiliensis and Elleanthus crinipes, and to analyze the chemical composition of their secretion to better understand the functions of these secretory structures. Due to the low frequency of colleters and lack of visible secretion in E. crinipes, histochemical tests and chemical analyses were not performed for this species. Colleters are of a brush type and their secretion has, at the same time, hydrophilic and lipophilic components. Histochemical tests further revealed the presence of pectin, mucilage, lipids, terpenes, phenolic compounds, and proteins. The GC-MS analysis confirmed the presence of γ-sitosterol and palmitic, linoleic, and stearic acids in the secretion of E. brasiliensis. Infrared analysis indicated the possible presence of polysaccharides in the secretion. The occurrence of colleters in both species studied and in other orchids described in the literature suggests that these structures are common in the inflorescences of tropical orchids. In these environments, the hydrated polysaccharides in the secretion form a dense matrix that can act as a physical barrier, and terpenes may help to protect against herbivores and pathogenic microorganisms. This information broadens our knowledge of the morphological and chemical diversity of the secretions produced by orchid colleters

    Morphoanatomy and phytochemistry of species of Lychnophorinae subtribe (Asteraceae: Vernonieae) as subsidies for the phylogenetic analyses of group

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    Orientadores: Beatriz Appezzato da Glória, Fernando Batista da CostaTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Asteraceae é uma das maiores famílias entre as angiospermas, possuindo de 24.000 a 30.000 espécies, o que representa, aproximadamente, 10% da flora mundial. Atualmente são reconhecidas 21 subtribos pertencentes à Vernonieae. Entre elas, Lychnophorinae tem uma distribuição quase restrita ao Brasil, ocorrendo nos campos rupestres e cerrados do Planalto Central. A subtribo apresenta 18 gêneros e 104 espécies, distribuídos entre os mais variados hábitos: ervas perenes, arbustos, subarbustos, arvoretas, árvores e caulirosuletum. Estudos filogenéticos recentes indicam que a subtribo é monofilética. As linhagens mais basais e mais derivadas são bem sustentadas, contudo, as relações entre os demais clados persistem apenas parcialmente resolvidas. Por esse motivo, nesse estudo são investigadas espécies da subtribo em relação à morfoanatomia e à química dos principais metabólitos de caules aéreos e folhas, buscando-se novos caracteres que possam ser úteis para um melhor entendimento evolutivo do grupo, inclusive possíveis sinapomorfias. Para tanto, foram eleitas espécies chaves dentro de Lychnophorinae, representantes das principais linhagens. Para as análises estruturais e histoquímicas, amostras de caules e de folhas foram processadas de acordo com as técnicas usuais em anatomia vegetal. Para as análises fitoquímicas, os extratos foram analisados por cromatografia liquida e espectrometria de massas. As reconstruções dos estados ancestrais dos caracteres foram efetuadas em uma filogenia baseada em dados morfológicos e moleculares. Em Lychnophorinae, os principais locais de síntese dos metabólitos secundários são: tricomas glandulares, idioblastos epidérmicos e tecidos parenquimáticos das folhas e dos caules. As análises fitoquímicas evidenciaram a presença de flavonoides, derivados do ácido trans-cinâmico, lactonas sesquiterpênicas e poliacetilenos. A reconstrução dos estados ancestrais dessas substâncias na filogenia da subtribo indicam possíveis sinapomorfias químicas. No decorrer das análises morfoanatômicas foram observadas duas importantes novidades em Lychnophorinae. A primeira relata a ocorrência de fitomelanina em caules aéreos e folhas de Lychnophorinae. As reconstruções dos estados ancestrais dos caracteres sugerem que o ancestral comum mais recente das Lychnophorinae já apresentava fitomelanina no caule espessado. A segunda novidade morfoanatômica diz respeito a um modo não usual de retenção de água sobre ápices caulinares, onde uma substância hialina é resultado da degradação parietal de tricomas não glandulares, tendo natureza hidrofílica. Essa substância possivelmente apresenta a função de proteger os órgãos jovens contra dessecação. Durante as investigações anatômicas de caules e folhas de Lychnophorinae, nós observamos características peculiares, frequentemente relatadas como xéricas, e procuramos entender se tais características mostravam algum padrão que agrupava as espécies. Nós realizamos análises multivariadas levando em consideração tais características. Os resultados indicaram quatro grupos funcionais em Lychnophorinae e sinalizaram que as espécies agrupadas, ocupavam os mesmos nichos, os quais refletiam condições específicas nos diferentes ambientes. Finalmente, após a conclusão das análises anatômicas, as características foram mapeadas na filogenia de Lychnophorinae e geraram importantes informações, como a identificação de oito possíveis sinapomorfias. As informações geradas nesse estudo sugerem que a evolução da diversidade morfológica e anatômica em Lychnophorinae pode ter sido direcionada por pressões adaptativas, derivadas de fatores ecofisiológicos dos ambientes restritos em que habitam a maioria das espéciesAbstract: Asteraceae is one of the largest flowering plants families, with 24,000-30,000 species, representing approximately 10% of the world's flora. Currently, 21 subtribes are recognized in Vernonieae. Among them, Lychnophorinae is nearly endemic to Brazil, occurring in campos rupestres areas and savannas of Central Plateau. The subtribe has 18 genera and 104 species distributed among the various habits: perennial herbs, shrubs, subshrubs, treelets, trees and caulirosuletum. Recent phylogenetic studies show that the subtribe is monophyletic. The most "basal" and more "derived" strains are well supported, however, relationships between the remaining clades persist partially unresolved. Therefore, in this study, species of the subtribe are investigated in relation to morphoanatomy and chemistry of the main metabolites of aerial stems and leaves, searching for new characters that might be useful for a better understanding of the group evolution, including possible synapomorphies. To this aim, key species were chosen in Lychnophorinae, representing the principal lineages. For structural and histochemical analyzes, samples of leaves and stems were processed according to usual plant anatomy techniques. For phytochemical analysis, the extracts were analyzed by liquid chromatography and mass spectrometry. Reconstructions of ancestral states of the characters was performed using parsimony in a phylogeny based on morphological and molecular data. In Lychnophorinae, the major sites of synthesis of secondary metabolites are: glandular trichomes, epidermal idioblasts and parenchyma of the leaves and stems. The phytochemical analysis revealed the presence of flavonoids, derivatives of trans-cinnamic acid, sesquiterpene lactones and polyacetylenes. The reconstruction of ancestral states of these substances in the phylogeny of the subtribe indicate possible chemical synapomorphies. During the morphoanatomic analyzes two important events in Lychnophorinae were observed. The first reports the occurrence of phytomelanin aerial stems and leaves of Lychnophorinae. Reconstructions of ancestral states of the characters suggest that the most recent common ancestral of Lychnophorinae presented phytomelanin in thickened stem. The second morphoanatomical novelty relates to a method of unusual water retention of apexes, where a substance hyaline is a result of parietal degradation of non glandular trichomes, and it has hydrophilic nature. This substance probably has the function to protect young organs from desiccation. During the anatomical investigations of stems and leaves of Lychnophorinae, we observed frequently reported as xeric peculiar characteristics, and seek to understand whether these characteristics showed some pattern that grouped species. We performed multivariate analysis taking into account the peculiar characteristics. The results indicated four functional groups Lychnophorinae and signaled that grouped species occupy the same niche, which reflect specific conditions in different environments. Finally, after completing the anatomical analyzes, the features were mapped on the phylogeny of Lychnophorinae and generated important information such as the identification of eight possible synapomorphies. The information generated in this study suggest that the evolution of morphological and anatomical diversity in Lychnophorinae may have been driven by adaptive pressures, derived from ecophysiological factors of restricted environments in which most species inhabitDoutoradoBiologia VegetalDoutora em Biologia Vegeta

    Trichomes Related To An Unusual Method Of Water Retention And Protection Of The Stem Apex In An Arid Zone Perennial Species

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)It is well known that trichomes protect plant organs, and several studies have investigated their role in the adaptation of plants to harsh environments. Recent studies have shown that the production of hydrophilic substances by glandular trichomes and the deposition of this secretion on young organs may facilitate water retention, thus preventing desiccation and favouring organ growth until the plant develops other protective mechanisms. Lychnophora diamantinana is a species endemic to the Brazilian 'campos rupestres' (rocky fields), a region characterized by intense solar radiation and water deficits. This study sought to investigate trichomes and the origin of the substances observed on the stem apices of L. diamantinana. Samples of stem apices, young and expanded leaves were studied using standard techniques, including light microscopy and scanning and transmission electron microscopy. Histochemical tests were used to identify the major groups of metabolites present in the trichomes and the hyaline material deposited on the apices. Non-glandular trichomes and glandular trichomes were observed. The material deposited on the stem apices was hyaline, highly hydrophilic and viscous. This hyaline material primarily consists of carbohydrates that result from the partial degradation of the cell wall of uniseriate trichomes. This degradation occurs at the same time that glandular trichomes secrete terpenoids, phenolic compounds and proteins. These results suggest that the non-glandular trichomes on the leaves of L. diamantinana help protect the young organ, particularly against desiccation, by deposition of highly hydrated substances on the apices. Furthermore, the secretion of glandular trichomes probably repels herbivore and pathogen attacks.7Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [302776/2010- 9, 302657/2011-8]FAPESP [2010/51454-3, 2010/02085-5
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