RCAAP Repository

Resumo Apresenta-se aqui o levantamento florístico da família Alismataceae latu sensu para o estado do Ceará, Nordeste do Brasil, região caracterizada por clima semiárido, onde são abundantes os ecossistemas aquáticos temporários. Quatro gêneros e 13 espécies foram identificados. As espécies indicadas para o estado são: Sagittaria guayanensis, S. planitiana, Echinodorus tenellus, E. glandulosus, E. pubescens, E. subalatus, E. palaefolius, E. floribundus, E. lanceolatus, Limnocharis laforestii, L. flava, Hydrocleys martii, H. nymphoides. São apresentadas descrições, comentários taxonômicos, ilustrações, chaves de identificação e dados da distribuição geográfica das espécies.

A avaliação da sensibilidade gustativa ao sal é utilizada na área da saúde, bem como em análise sensorial aplicada à Ciência e Tecnologia de Alimentos, para avaliar o paladar e identificar ageusia e hipoageusia de diversas origens; notavelmente, identifica os indivíduos que apresentam risco ou consumo excessivo de sal. A adoção de um método acurado e reprodutível para avaliação do limiar gustativo ao sal permite seu uso de forma ampliada. Esta revisão integrativa tem como objetivo descrever as metodologias empregadas para avaliar o limiar de detecção e reconhecimento do cloreto de sódio. Foram utilizadas as bases de dados CINAHAL, LILACS e MEDLINE, e as palavras-chave taste threshold, sodium chloride e salt. Foram localizados 27 artigos de 1985 a 2009 e, nestes, empregados 29 testes de análise do limiar. A maioria dos artigos utilizou o estímulo da boca toda (75,9%), seguida da aplicação tópica na língua (24,1%), aplicação da solução em partes da língua (10,3%), eletrogustometria (6,4%), disco impregnado (3,4%) e aplicação de vácuo (3,4%). Houve grande variação nos procedimentos metodológicos e, em alguns, ausência de informações importantes. Os artigos não apresentam cálculo do tamanho amostral e os critérios de seleção dos julgadores foram também variados. Assim, existe uma dificuldade para a reprodutibilidade e as comparações dos artigos. Avaliações comparativas entre os diferentes métodos de avaliação do limiar gustativo ao cloreto de sódio quanto à sua reprodutibilidade podem trazer subsídios importantes para a escolha do método mais adequado a ser empregado em pesquisa e na prática clínica.

Abstract The effects of Urucu crude oil on growth and biomass production of Echinochloa polystachya were studied experimentally. Young plants contaminated with 5 oil doses (0 to 2.64 l.m-2) were monitored at 1, 5, 10, 15 and 20 days after exposure. A significant reduction was observed in leaf humidity and the ratio of live aerial/ total biomass related to the increase in oil dosage. Increased exposition time caused a reduction in the number of leaves, aerial biomass, proportion of live aerial/total biomass, total biomass, and an increase of dead aerial biomass. However, root biomass and leaf length were not affected by exposure to oil. The low tolerance of E. polystachya to Urucu crude oil has lead to the mortality of 90% of the plant population in 20 days at the 2.64 l treatment. The death of young individuals of E. polystachya by relatively low dosages of Urucu oil indicates that, in the case of an oil spill in the Amazon varzea, this species would be severely affected, endangering, consequently, the entire environment.

The functional properties of corn starch based films were improved by incorporating nanoclay (Montmorillonite). Nanoclay was incorporated in the polymer matrix using two different methodologies and the films were formed by casting. The effect of film preparation methodology and of the nanoclay concentration on the physicochemical properties of the films was studied. Depending on film preparation method used, intercalated or exfoliated nanocomposite films were obtained. The FTIR spectra showed a strong interaction between the montmorillonite and the starch molecules. Opacity was dependent on the nanoclay dispersion method used. Water vapor solubility and permeability decreased with increasing montmorillonite content and were affected by the dispersion method. Water diffusion was only dependent on the nanoclay content due to the increase in tortuosity of the diffusion path, caused by the nanoparticles. The results showed that the incorporation of 5% of montmorillonite using an adequate dispersion method, improved the water resistance and barrier properties of corn starch based films. Nanoparticles reduced the damage caused to the properties of these hydrophilic films by the increase in moisture content.

Abstract The phytoremediation technique, which consists of using plants to remove ions, has been increasingly chosen over past decades due to its low-cost technology to mitigate contaminated areas. The aim of this study was to evaluate the potential of the aquatic macrophytes, Azolla caroliniana Willd, Salvinia minima Baker and Spirodela polyrhiza (L.) Schleiden, to accumulate manganese (Mn), an element which, at high concentrations, may be toxic to human populations. The three species accumulated Mn in their tissues and the absorption was independent of the metal concentration in the solution. Spirodela polyrhiza accumulated Mn at higher concentrations of the ion (17.062 mg g-1 MS), followed by S. minima (4.283 mg g-1 MS) and A. caroliniana (1.341 mg g-1 MS). Manganese excess reduced total chlorophyll content in all three species. Carotenoid content was reduced in A. caroliniana (27.02 %) and S. polyrhiza (25.34 %). Growth was only significantly reduced (21.34%) in S. polyrhiza. The species A. caroliniana and S. minima were able to tolerate excess Mn, but were inefficient regarding the accumulation of high concentrations of the metal. High accumulated Mn content in the tissues of S. polyrhiza suggests that the species is able to accumulate this element. Therefore, it has potential for use in phytoremediation and provides a new resource for exploring the Mn accumulation mechanism.

Abstract Reproductive biology and pollination of the fanwort, Cabomba aquatica Aubl., were studied in populations from dams located in Dois Irmãos State Park, Recife, Pernambuco state, northeastern Brazil. Flower anthesis in this species is diurnal and lasts two days. The flowers are bisexual and exhibit herkogamy and incomplete protogyny. Each flower produces an average of 2.1 ± 94.8 pollen grains, with a P/O ratio of 1.055 and high pollen viability (99.7%). This species is self-compatible, but requires biotic vectors to transfer pollen. We observed visits of bees (Apidae and Halictidae), wasps (Vespidae) and flies (Diptera) to the flowers. Bees and wasps were considered to be effective pollinators, both due to their behavior and their high frequency of visits to flowers, whereas flies were considered to be occasional pollinators. The floral mechanism (herkogamy and protogyny), together with low nectar production and pollinator behavior during visits, may contribute to increase pollen flow between individuals.

Abstract Aquatic macrophytes show great phenotypic plasticity and are able to occupy environments with different physicochemical conditions. The present study aimed to characterize morphology and anatomical structure of the pondweed, Potamogeton polygonus Cham. & Schltdl., and to identify adaptive modifications of the plant in lotic and lentic environments. Sampling was carried out in Palmas and General Carneiro, Paraná state, southern Brazil. Ten individuals from each locality were collected. Morpho-anatomical characteristics of the roots, stems and leaves were measured. The anatomical structure was analyzed with light microscopy and scanning electron microscopy. Significant morphological and anatomical adaptive differences were observed between plants of the two environments.

Abstract Podostemaceae is a family of eudicotyledonous rheophytes with unique morphology, sometimes resembling algae, lichens or bryophytes. This study evaluates the taxonomic value of silica-body morphology (presence, location, size, shape, ornamentation) in species representing the three subfamilies: Tristicha trifaria (Bory ex Willd.) Spreng. (Tristichoideae), Weddellina squamulosa Tul. (Weddellinoideae) and Diamantina lombardii Novelo, C.T. Philbrick & Irgang (Podostemoideae). T. trifaria and D. lombardii have silica bodies in stems and leaves. In contrast, W. squamulosa exhibits silica bodies only in the scale-like leaves. The morphology of these bodies is unique to each species. The results denote the taxonomic usefulness of silica characteristics and a need for a more complete study of silica bodies throughout the family.

The pantropical family Eriocaulaceae includes ten genera and c. 1,400 species, with diversity concentrated in the New World. The last complete revision of the family was published more than 100 years ago, and until recently the generic and infrageneric relationships were poorly resolved. However, a multi-disciplinary approach over the last 30 years, using morphological and anatomical characters, has been supplemented with additional data from palynology, chemistry, embryology, population genetics, cytology and, more recently, molecular phylogenetic studies. This led to a reassessment of phylogenetic relationships within the family. In this paper we present new data for the ITS and trnL-F regions, analysed separately and in combination, using maximum parsimony and Bayesian inference. The data confirm previous results, and show that many characters traditionally used for differentiating and circumscribing the genera within the family are homoplasious. A new generic key with characters from various sources and reflecting the current taxonomic changes is presented.

A well-studied group of plants can serve as a model for addressing issues in conservation, evolution, and biogeography, making it possible to assign conservation status with confidence and detecting not only those taxa that are most threatened but also those that represent basal, unique, and/or relictual members of entire lineages. Clarified higher-level phylogenetic relationships open the door to more refined systematics of clades without having to worry if they are para- or polyphyletic. A well-studied group can also be an excellent testing ground for new or under-utilized tools and independent data sets. Research on the Burseraceae, with over 100 taxa in the Amazon, is rapidly arriving at the point where the family can be used effectively both as a tool for conservation and as a model for studying the processes influencing the origin and maintenance of high diversity in the Amazonian flora. First, we are resolving higher-level phylogenies as well as species-level taxonomy in various clades, allowing comparative approaches. Second, the family occurs throughout Amazonia and is well-represented in most habitats overall, but most of the taxa are restricted in their distributions and/or habitats; this makes it possible to test the relative importance of geographic barriers vs. habitat diversity in the speciation process. The family is sufficiently large to provide adequate statistical power for hypothesis testing and yet small enough to achieve the necessary sampling intensity, allowing us to assess the relative impacts of morphological innovation, ecological opportunity, and biogeographic events on the diversification of Burseraceae and related groups.

The risk assessment is made up of risk analyses of species extinction in a given time, following the International Union for Conservation of Nature and Natural Resources (IUCN) criteria. In Brazil, the data necessary for risk assessments have poor quality, so we proposed the articulation of previous processes to improve data quality. The main objective of this work was to reassess the extinction risk of Brazilian species of Combretaceae previously considered as threatened, updating conservation data available for these taxa. Our results showed that the processes of taxonomic proceedings; data gathering; data analysis; georeferencing and communication improved the assessments consistency, specially due to systematization of the whole process. Of the 11 selected species for reassessment, five were threatened in the categories VU, EN, CR e CR* and six under significant threat of extinction. However the deficiency of herbaria data, the lack of digitalization of the majority of country collections and the limited access to available literature represent the main obstacles for extinction risk assessments of the Brazilian flora.

Asteraceae is one of the most abundant families of the Brazilian flora, and it stands out on Brazilian red lists due to the large number of endangered and data-deficient species, since it is difficult to define a conservation status for the latter. A comparative analysis of red lists of the Brazilian flora focused on the Asteraceae is important, so we can assess the true degree of threat to which these plants are subjected faced with increasing environmental degradation. Our analysis compared red lists, and pointed out the most threatened species or data-deficient areas, species and genera. The study was based on the first and the current Official List of Endangered Species of the Brazilian Flora, and the Brazilian Flora Red List of Fundação Biodiversitas. Species were organized according to the endangered and data-deficient IUCN categories. Endangered species were also classified according to threat category. The highest numbers of threatened species were observed in the Cerrado, in the southeastern region, and in the state of Minas Gerais, as well as in the genera Lychnophora Mart., Vernonia Schreb., and Richterago Kuntze. The genera Aspilia Thouars, Baccharis L., Calea L., Eupatorium L., Mikania Willd., Piptocarpha R.Br., and Senecio L. have the greatest number of data-deficient species. Since the current Official List does not make clear its threat criteria, the Red List of Fundação Biodiversitas best portrays the situation of endangered Asteraceae species; thus, this analysis provides important information for projects aimed at the conservation of threatened and data-deficient species.

The identification of Amazonian plants is still difficult for many reasons, one being the lack of collections over large areas of the region. As a consequence of the poor knowledge on the Amazonian flora, many taxonomic publications (revisions and floristic treatments) become out of date within a few years. In this context, the on-line publication of taxonomic treatises has been suggested, since it allows constant data updates; and this type of publication should therefore be more valued by the scientific community. An excellent field guide for the Ducke Reserve (Manaus, central Amazonian Brazil) was published, based exclusively on vegetative characters. However, the presence of reproductive structures in the collected material does not facilitate identification with this type of field guide. Furthermore, as in any printed key, the text cannot be updated, except through a new edition. As an example of a way to facilitate the identification of Amazonian plants, an interactive, multiple-entry key to the seed plant genera that occur in the Ducke Reserve was created using the program Lucid 3.5. The key includes vegetative and reproductive characters and many illustrations, and is available on-line. We discuss here the peculiarities and advantages of this type of electronic publication.

As investigações sobre a morfologia de plântulas, antes do surgimento dos metafilos, têm demonstrado rico potencial para estudos sistemáticos, inclusive testando a monofilia de gêneros de Leguminosae. Além disso, proporcionam a descoberta de estruturas transitórias, basais ou derivadas, que podem estabelecer conexões nem sempre ocorrentes no indivíduo adulto. A natureza dos cotilédones, de reserva ou folíaceos, é uma das principais características das leguminosae. O tipo de germinação constitui um dos caracteres mais relevantes para diferenciar suas espécies, assim como a forma do limbo, da margem, do ápice, posição dos eofilos, presença ou ausência de látex ou resina, relação comprimento/largura dos cotilédones, tamanho e número de pinas, pecíolo alado ou não, que permitem caracterizar famílias, gêneros e até mesmo espécies. Em Leguminosae, a morfologia de plântulas corrobora a identificação das plantas no campo e ainda fornece subsídios para delimitações genéricas e infragenéricas na família. De uma maneira geral as plântulas de Caesalpinioideae e Mimosoideae são epígeas, com cotilédones foliáceos; em Papilionoideae predominam plântulas hipógeas com cotilédones de reserva e extremamente variadas em termos morfológicos, principalmente nas tribos com espécies lenhosas.

The Apocynaceae comprise approximately 5,000 species and are widely distributed. The family belongs to the Gentianales and can be easily recognized by the presence of latex and a style-head derived from the fusion of two carpels at the apex of the styles. The largest subfamily in Apocynaceae is Asclepiadoideae. Treated as the Asclepiadaceae for almost two centuries, it comprises about 3,000 species and is defined by stamens with bisporangiate anthers and pollen transferred in specialized units called pollinaria. Since the 19th century, floristic studies and taxonomic monographs have significantly contributed to the taxonomy of Brazilian Asclepiadoideae. Nevertheless, advances in understanding the internal relationships in the subfamily were not done until this millennium, with the popularization of phylogenetic studies based on molecular data and powerful computer analyses. Advances in the systematics of Apocynaceae have provided new interpretations on the morphological evolution and biogeography of the family and have led to important changes in its classification. Nevertheless, several taxonomic rearrangements are still needed and it can be said that the taxonomy of Apocynaceae is "under construction". In this article, the major taxonomic changes in the family are reviewed, with special attention given to the systematics of Neotropical groups. A cladogram of the Apocynaceae is presented, which highlights the phylogenetic position of the Brazilian genera and their diversity in number of native species. The main studies and the diversity of Asclepiadoideae in Brazil are summarized and perspectives for future research on the subfamily are presented.

A summary of the classification of Poaceae into subfamilies according to different proposals is provided, as well as data on morphology and chorology of grasses, especially those that occur in Brazil.

The Rubiaceae is the fourth Angiosperm family in number of species in the World and in the Neotropics. Its overwhelming diversity and presence in most biomes, and at most vegetation layers, makes this family one of the most important components of tropical vegetation. During the last two decades, family classification went through several reorganizations, mostly influenced by the advent of molecular phylogenetic studies, and many taxonomic revisions and floristic studies on Brazilian Rubiaceae have become available. In view of the considerable amount of literature that has recently been produced on Neotropical Rubiaceae, the present work has two main objectives: the first is to offer an overall view of the most recent family classification with emphasis on the genera of Rubiaceae occurring in Brazil, and to indicate particular taxa that are still in need of phylogenetic and taxonomic studies; the second objective is to present a short discussion on the state of floristic and taxonomic knowledge with respect to the various regions of Brazil, indicating the taxa and the geographic areas that need to be studied.

A checklist and keys are provided for Lamiaceae native to Brazilian Amazonia (eight genera and 42 species), excluding the genera Vitex, Volkameria, Aegiphila and Amasonia, which have recently been transferred from the Verbenaceae, and for which the author did not have data. An herbarium voucher is listed for each state in which the species has been found. Notes on many cultivated taxa are included, and also a key to all species of Ocimum known from Brazil.

Uma retrospectiva do conhecimento taxonômico atual de Melastomataceae no Brasil é apresentada, constando uma abordagem histórica dos estudos já desenvolvidos e o cenário atual das circunscrições da família, tribos e gêneros. Também é abordada a distribuição geográfica do grupo nos diferentes domínios fitogeográficos, bem como o uso de novas ferramentas metodológicas, como filogenia e marcadores moleculares, para subsidiar propostas de novas classificações da família. São destacadas perspectivas de futuros estudos que possam contribuir para atualizar e preencher lacunas no conhecimento da diversidade do grupo na flora brasileira e apresentada uma chave de identificação para os gêneros no Brasil.

Pera Mutis é um gênero neotropical, com aproximadamente 30 espécies e centro de diversidade localizado na Bacia Amazônica. São árvores ou arbustos, dióicos ou raramente monóicos, que apresentam uma bráctea globosa que às vezes é confundida com botões florais. A última revisão do gênero foi realizada em 1919, sendo que muitas espécies foram descritas desde então. Este trabalho objetiva realizar um estudo taxonômico das espécies de Pera que ocorrem na Amazônia brasileira, discutindo a posição do gênero como parte de um táxon autônomo (Peraceae) ou como membro das Euphorbiaceae s.s. Foram encontradas 13 espécies na Amazônia brasileira: P. anisotricha Müll. Arg., P. bicolor (Klotzsch) Müll. Arg., P. benensis Ruby, P. coccinea (Benth.) Müll. Arg., P. decipiens Müll. Arg., P. distichophylla (Mart.) Baill., P. eiteniorum Bigio & Secco, P. glabrata (Schott) Baill., P. heteranthera (Schranck) I.M. Johnst, P. manausensis Bigio & Secco, P. membranacea Leal,P. tomentosa (Benth.) Müll. Arg. e P. pulchrifolia Ducke. Destas, três são novas ocorrências para a Amazônia brasileira, oito táxons foram considerados como novos sinônimos e novos lectótipos foram designados. Um histórico taxônomico do gênero, informações sobre sua morfologia, bem como descrições, chave de identificação, ilustrações e informações sobre a biologia de cada espécie são fornecidos.