21 research outputs found

    Variation in plant-animal interactions along an elevational gradient of moist forest in a semiarid area of Brazil

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    Pollination and dispersal are critical ecological processes that directly affect the reproductive success of plants and are important for understanding the structure of plant communities. We compiled data on pollination and dispersal syndromes of 406 plant species distributed among different elevations in Area de Protecao Ambiental da Serra de Baturite (APASB) in northeastern Brazil. We aim to determine how the dispersal and pollination of the flora in the mountainous rainforest of APASB are affected by climate, relief and growth form. We hypothesized that plant community is comprised of different ecological groups based on biotic and abiotic syndromes. Melittophily was the most common (57%) pollination syndrome followed by non-specialized and ornithophily (7%). We found that 64% of species exhibited zoochory, 19% exhibited anemochory and 17% exhibited autochory. Pollination syndromes differed significantly only between types of growth form. Dispersal syndromes differed between topology, growth form and elevation. Six ecological groups were formed based on the interaction between dispersal-pollination and growth form, with predominantly zoochory in woody and anemochory in non-woody plants. Water availability may be the principal factor responsible for variation among dispersal syndromes. The proportion of ruderal species in the non-woody component explains the differences in syndromes between growth forms3012734CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP552213/2011-0; 479263/2011-6; 563537/2010-8PROCAD 157/2007PP1-0033-00025.01.00/1

    Evolution of exceptional species richness among lineages of fleshy-fruited Myrtaceae

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    Background and Aims: The angiosperm family Myrtaceae comprises 17 tribes with more than half of the estimated 5500 species being referred to the fleshy-fruited and predominantly rainforest associated Syzygieae and Myrteae. Previous studies suggest that fleshy fruits have evolved separately in these lineages, whereas generally shifts in fruit morphology have been variously implicated in diversification rate shifts among angiosperms. A phylogenetic hypothesis and estimate divergence times for Myrtaceae is developed as a basis to explore the evidence for, and drivers of, elevated diversification rates among the fleshy-fruited tribes of Myrtaceae. Methods: Bayesian phylogenetic analyses of plastid and nuclear DNA sequences were used to estimate intertribal relationships and lineage divergence times in Myrtaceae. Focusing on the fleshy-fruited tribes, a variety of statistical approaches were used to assess diversification rates and diversification rate shifts across the family. Key Results: Analyses of the sequence data provide a strongly supported phylogenetic hypothesis for Myrtaceae. Relative to previous studies, substantially younger ages for many of the clades are reported, and it is argued that the use of flexible calibrations to incorporate fossil data provides more realistic divergence estimates than the use of errorless point calibrations. It is found that Syzygieae and Myrteae have experienced elevated diversification rates relative to other lineages of Myrtaceae. Positive shifts in diversification rate have occurred separately in each lineage, associated with a shift from dry to fleshy fruit. Conclusions: Fleshy fruits have evolved independently in Syzygieae and Myrteae, and this is accompanied by exceptional diversification rate shifts in both instances, suggesting that the evolution of fleshy fruits is a key innovation for rainforest Myrtaceae. Noting the scale dependency of this hypothesis, more complex explanations may be required to explain diversification rate shifts occurring within the fleshy-fruited tribes, and the suggested phylogenetic hypothesis provides an appropriate framework for this undertaking

    Evolution of exceptional species richness among lineages of fleshy-fruited Myrtaceae

    No full text
    Background and Aims The angiosperm family Myrtaceae comprises 17 tribes with more than half of the estimated 5500 species being referred to the fleshy-fruited and predominantly rainforest associated Syzygieae and Myrteae. Previous studies suggest that fleshy fruits have evolved separately in these lineages, whereas generally shifts in fruit morphology have been variously implicated in diversification rate shifts among angiosperms. A phylogenetic hypothesis and estimate divergence times for Myrtaceae is developed as a basis to explore the evidence for, and drivers of, elevated diversification rates among the fleshy-fruited tribes of Myrtaceae. Methods Bayesian phylogenetic analyses of plastid and nuclear DNA sequences were used to estimate intertribal relationships and lineage divergence times in Myrtaceae. Focusing on the fleshy-fruited tribes, a variety of statistical approaches were used to assess diversification rates and diversification rate shifts across the family. Key Results Analyses of the sequence data provide a strongly supported phylogenetic hypothesis for Myrtaceae. Relative to previous studies, substantially younger ages for many of the clades are reported, and it is argued that the use of flexible calibrations to incorporate fossil data provides more realistic divergence estimates than the use of errorless point calibrations. It is found that Syzygieae and Myrteae have experienced elevated diversification rates relative to other lineages of Myrtaceae. Positive shifts in diversification rate have occurred separately in each lineage, associated with a shift from dry to fleshy fruit. Conclusions Fleshy fruits have evolved independently in Syzygieae and Myrteae, and this is accompanied by exceptional diversification rate shifts in both instances, suggesting that the evolution of fleshy fruits is a key innovation for rainforest Myrtaceae. Noting the scale dependency of this hypothesis, more complex explanations may be required to explain diversification rate shifts occurring within the fleshy-fruited tribes, and the suggested phylogenetic hypothesis provides an appropriate framework for this undertaking

    Caracterização agronômica de Ocimum gratissimum L (alfavaca-cravo) e Ocimum sp (alfavaca-roxa) cultivadas em casa de vegetação e ambiente externo

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    O crescimento das plantas pode ser acompanhado ao longo do tempo, por meio da determinação de variáveis como matéria seca e área foliar, visto que se relaciona ao aumento da matéria seca a partir da conversão de substâncias inorgânicas simples em substâncias orgânicas, pelo processo da fotossíntese. A partir da avaliação dos dados de crescimento podem ser desenvolvidas técnicas de manejo das espécies, ou podem ser estimadas as causas da variação entre plantas que crescem em diferentes ambientes. Quanto à caracterização agronômica de plantas medicinais, apesar da riqueza da diversidade de plantas com propriedades terapêuticas no Brasil e da ampla utilização da medicina natural pelas populações, há necessidade de mais estudos sobre o tema. Diante disso, foi realizado um experimento com o objetivo de melhorar os conhecimentos sobre as práticas de cultivo de plantas de interesse medicinal. Para avaliar as características de crescimento de alfavaca-cravo e alfavaca-roxa foi instalado um experimento em casa de vegetação (50% de sombra) e ambiente externo, em pleno sol (0% sombra). As características analisadas foram: diâmetro do caule, altura, nº de folhas, área foliar, comprimento da raiz e massa da matéria seca. As plantas das duas espécies apresentaram maior produção de biomassa em condição de pleno sol

    Phylogenetic relationships, distribution, and conservation of Roosmalens’ dwarf porcupine, Coendou roosmalenorum Voss & da Silva, 2001 (Rodentia, Erethizontidae)

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    The New World porcupines of the genus Coendou comprise 16 species of arboreal nocturnal rodents. Some of these species are poorly known and have not been included in phylogenetic analyses. Based on recently collected specimens with associated tissue from the Brazilian Amazonia, we investigate the distribution and phylogenetic relationships of Roosmalens’ dwarf porcupine, Coendou roosmalenorum, using an integrative approach using mitochondrial gene sequences and morphological data from new specimens and localities. Our results recovered C. roosmalenorum in the subgenus Caaporamys. However, analyses of our molecular and combined datasets produced different topologies. The new record shows the presence of C. roosmalenorum 480 km to the southeast of the Rio Madeira and 95 km away from Rio Juruena in Mato Grosso state, indicating a wider distribution in southern Amazonia than suspected. All known records of C. roosmalenorum are in the Madeira biogeographical province, to which it might be endemic
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