RESUMEN
Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods1,2. A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome3,4. Many studies have drawn on this foundational work, such as classification and first insights into angiosperm diversification since their Mesozoic origins5-7. However, the limited and biased sampling of both taxa and genomes undermines confidence in the tree and its implications. Here, we build the tree of life for almost 8,000 (about 60%) angiosperm genera using a standardized set of 353 nuclear genes8. This 15-fold increase in genus-level sampling relative to comparable nuclear studies9 provides a critical test of earlier results and brings notable change to key groups, especially in rosids, while substantiating many previously predicted relationships. Scaling this tree to time using 200 fossils, we discovered that early angiosperm evolution was characterized by high gene tree conflict and explosive diversification, giving rise to more than 80% of extant angiosperm orders. Steady diversification ensued through the remaining Mesozoic Era until rates resurged in the Cenozoic Era, concurrent with decreasing global temperatures and tightly linked with gene tree conflict. Taken together, our extensive sampling combined with advanced phylogenomic methods shows the deep history and full complexity in the evolution of a megadiverse clade.
Asunto(s)
Evolución Molecular , Genes de Plantas , Genómica , Magnoliopsida , Filogenia , Fósiles , Genes de Plantas/genética , Magnoliopsida/genética , Magnoliopsida/clasificación , Proteínas Nucleares/genéticaRESUMEN
PREMISE: Characterization and phylogenetic integration of fossil angiosperms with uncertain affinities is relatively limited, which may obscure the diversity of extinct higher taxa in the flowering plant tree of life. The order Cornales contains a diversity of extinct taxa with uncertain familial affinities that make it an ideal group for studying turnover in angiosperms. Here, we describe a new extinct genus of Cornales unassignable to an extant family and conduct a series of phylogenetic analyses to reconstruct relationships of fossils across the order. METHODS: Two permineralized endocarps were collected from the Cedar District Formation (Campanian, 82-80 Ma) of Sucia Island, State of Washington, United States. Fossils were sectioned with the cellulose acetate peel technique and incorporated into a morphological dataset. To assess the utility of this dataset to accurately place taxa in their respective clades, we used a series of phylogenetic pseudofossilization analyses. We then conducted a total-evidence analysis and a scaffold-based approach to determine relationships of fossils. RESULTS: Based on their unique combination of characters, the fossils represent a new genus, Fenestracarpa washingtonensis gen. nov. et sp. nov. Pseudofossilization analyses indicate that our morphological dataset can be used to accurately recover taxa at the major clade to family level, generally with moderate to high support. The total-evidence and scaffold-based analyses recovered Fenestracarpa and other fossil genera in an entirely extinct clade within Cornales. CONCLUSIONS: Our findings increase the reported diversity of extinct Cornales and indicate that the order's initial radiation likely included the divergence of an extinct higher clade that endured the end-Cretaceous Mass extinction but perished during the Cenozoic.
Asunto(s)
Extinción Biológica , Fósiles , Filogenia , Fósiles/anatomía & histología , Magnoliopsida/anatomía & histología , Magnoliopsida/genética , Magnoliopsida/clasificación , WashingtónRESUMEN
Spatio-temporal assessment of phylogenetic diversity gradients during the Holocene (past 12,000 years) provides an opportunity for a deeper understanding of the dynamics of species co-occurrence patterns under environmental fluctuations. Using two robust metrics of phylogenetic dispersion (PD) and 99 fossil pollen sequences containing 6557 samples/assemblages, we analyse spatio-temporal variation in PD of angiosperms and its relationship with Holocene climate in central Asia. Overall, PD throughout the Holocene decreases linearly with increasing latitude, except for a rise in mean nearest taxon distance from ca. 25 to 35° N. This indicates that phylogenetically divergent taxa decrease progressively with increasing latitude, leaving more phylogenetically closely related taxa in the assemblages, thereby increasing phylogenetic relatedness among the co-occurring taxa. The latitudinal gradient of PD has not been consistent during the Holocene, and this temporal variation is concordant with the Holocene climate dynamics. In general, profound temporal changes in the latitudinal PD toward higher latitudes implies that the major environmental changes during the Holocene have driven considerable spatio-temporal changes in the phylogenetic assembly of high-latitude angiosperm assemblages. Our results suggest that environmental filtering and the tendency of taxa and lineages to retain ancestral ecological features and geographic distributions (phylogenetic niche conservatism) are the main mechanisms underlying the phylogenetic assembly of angiosperms along the climate-latitudinal gradient. Ongoing environmental changes may pose future profound phylogenetic changes in high-latitude plant assemblages, which are adapted to harsh environmental conditions, and therefore are phylogenetically less dispersed (more conservative or clustered).
Asunto(s)
Fósiles , Magnoliopsida , Filogenia , Magnoliopsida/genética , Magnoliopsida/clasificación , Asia , Clima , Polen/genética , BiodiversidadRESUMEN
BACKGROUND Endophytic fungi, present mainly in the Ascomycota and Basidiomycota phyla, are associated with different plants and represent important producers of bioactive natural products. Brazil has a rich biodiversity of plant species, including those reported as being endemic. Among the endemic Brazilian plant species, Vellozia gigantea (Velloziaceae) is threatened by extinction and is a promising target to recover endophytic fungi. OBJECTIVE The present study focused on bioprospecting of bioactive compounds of the endophytic fungi associated with V. gigantea, an endemic, ancient, and endangered plant species that occurs only in the rupestrian grasslands of Brazil. METHODS The capability of 285 fungal isolates to produce antimicrobial and antimalarial activities was examined. Fungi were grown at solid-state fermentation to recover their crude extracts in dichloromethane. Bioactive extracts were analysed by chromatographic fractionation and NMR and displayed compounds with antimicrobial, antimycobacterial, and antimalarial activities. FINDINGS Five fungi produced antimicrobial and antimalarial compounds. Extracts of Diaporthe miriciae showed antifungal, antibacterial, and antimalarial activities; Trichoderma effusum displayed selective antibacterial activity against methicillin-resistant Staphylococcus aureus and Mycobacterium intracellulare; and three Penicillium species showed antibacterial activity. D. miriciae extract contained highly functionalised secondary metabolites, yielding the compound epoxycytochalasin H with high antimalarial activity against the chloroquine-resistant strain of Plasmodium falciparum, with an IC50 approximately 3.5-fold lower than that with chloroquine. MAIN CONCLUSION Our results indicate that V. gigantea may represent a microhabitat repository hotspot of potential fungi producers of bioactive compounds and suggest that endophytic fungal communities might be an important biological component contributing to the fitness of the plants living in the rupestrian grassland.
Asunto(s)
Plasmodium/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Magnoliopsida/clasificación , Magnoliopsida/microbiología , Hongos Mitospóricos/efectos de los fármacos , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Antimaláricos/aislamiento & purificación , Antimaláricos/farmacología , Clima Tropical , Bioensayo , Candida/efectos de los fármacos , Endófitos/químicaRESUMEN
Abstract Macrophytes may constitute an important resource for several chemical, physical and biological processes within aquatic ecosystems. This study considers that in tropical reservoirs with low retention time and with low values of shoreline development (DL), the expansion and persistence of aquatic macrophytes are mainly reported to local conditions (e.g., hydrodynamic and wind exposure) rather than trophic status and depth of the euphotic zone. In this context, this study aimed at describing and comparing the incidence of aquatic macrophytes in a throughflowing, non-dendritic tropical reservoir. During February 2006 to November 2007, eight limnological surveys were performed quarterly within the Ourinhos Reservoir, and in the mouth areas of its tributaries. At the six sampling stations 30 variables were measured. The number of sites with plants varied between 21 and 38 and at the end of the 1st year the total richness was found. The sampling survey outcome the recognition of 18 species of aquatic macrophytes; Cyperaceae (2 genera and 1 species), Pontederiaceae (3 species) and Onarograceae (3 genera) were the families with higher diversity. Seven species (Typha domingensis Pers., Myriophyllum aquaticum (Vell.) Verdec, Salvinia auriculata Aubl., Eichhornia azurea (Sw.) Kunth, Eleocharis sp1, Eichhornia crassipes (Mart.) Solms, Oxycaryum cubense (Poepp. & Kunth) Lye) always were present and were more frequent in the sites. The occurrence of emergent species predominated (45.9%), followed by submersed rooted (24.5%), free floating (19.5%), floating rooted (9.7%) and free submersed (0.3%). Although limnological variables and the distribution of macrophytes have discriminated the same sampling points, the stepwise multiple linear regressions did not pointed out strong correspondences (or coherence) among the most constant and distributed macrophyte species and the selected limnological variables, as well the trophic statuses. Seeing the low relationship among limnological variables and macrophytes distribution, in the case of Ourinhos Reservoir, the results pointed out that the water turbulence, low DL and wind exposure are the main driving forces that determine its aquatic plant distribution, life forms and species composition.
Resumo As macrófitas podem constituir um recurso importante para vários processos físicos, químicos e biológicos dos ecossistemas aquáticos. Esse estudo considera que nos reservatórios tropicais com baixo tempo de retenção e com baixos valores do grau de desenvolvimento das margens (DL), a expansão e manutenção das macrófitas aquáticas são referidas principalmente às condições locais (e.g., hidrodinâmica e exposição ao vento), ao invés do estado trófico e da profundidade de zona eufótica. Nesse contexto, o presente estudo teve como objetivo descrever e comparar a incidência de macrófitas aquáticas em um reservatório tropical de fluxo rápido e não dendrítico. De fevereiro de 2006 a novembro de 2007, oito avaliações limnológicas foram realizadas trimestralmente no reservatório Ourinhos e nas regiões de desembocadura de seus afluentes. Nas seis estações de amostragem 30 variáveis foram determinadas. O número de locais com plantas variou entre 21 e 38 e no final do primeiro ano o número total de espécies foi encontrado. Foram relacionadas 18 espécies de macrófitas aquáticas; Cyperaceae (2 gêneros e espécies), Pontederiaceae (3 espécies) e Onarograceae (3 gêneros) foram as famílias com mais diversidade. Sete espécies (Typha domingensis Pers., Myriophyllum aquaticum (Vell.) Verdec, Salvinia auriculata Aubl., Eichhornia azurea (Sw.) Kunth, Eleocharis sp1, Eichhornia crassipes (Mart.) Solms, Oxycaryum cubense (Poepp. & Kunth) Lye) sempre estiveram presentes e foram as mais frequentes. As ocorrências de espécies emergentes predominaram (45,9%), seguidas das submersas enraizadas (24,5%), flutuantes livres (19,5%), flutuantes enraizadas (9,7%) e submersas livres (0,3%). Embora as variáveis limnológicas e as distribuições de macrófitas tenham discriminado os mesmo pontos de coleta, regressões lineares múltiplas stepwise não apontaram correspondências fortes (ou coerentes) entre as espécies de macrófitas mais constantes e distribuídas e as variáveis limnológicas, assim como os estados tróficos. No reservatório Ourinhos, a baixa relação entre as variáveis limnológicas e a distribuição das macrófitas aponta que a turbulência da água, o baixo valor de DL e a exposição ao vento sejam as principais forças que determinam a distribuição das plantas aquáticas, as suas formas de vida e a composição das espécies.
Asunto(s)
Recursos Hídricos , Ecosistema , Magnoliopsida/clasificación , Eichhornia/crecimiento & desarrolloRESUMEN
Floristic studies provide valuable information on species richness in a region, and are particularly important if these areas belong to less studied environments, such as rocky outcrops, that may increase our knowledge. An important aspect for species colonization includes the mechanisms of diaspores dispersal in each community; these are essential to understand its structure, dynamics, and the regeneration process, and constitute an important tool for conservation. We developed a floristic survey on a granite-gneiss outcrop with the objective to increase the knowledge on plant diversity, through a floristic similarity analysis and detection of dispersal syndromes of sampled species, in a semi-arid region of Brazil. The fieldwork included collection and observation of the botanical material in locoduring a period of 12 months. A total of 161 species belonging to 127 genera and 50 families of angiosperms were recorded. Fabaceae, Asteraceae and Convolvulaceae were the most representative families in number of species. Allophylus quercifolius(Mart.) Radlk. (Capparaceae) and Lafoensia pacariA. St.-Hil. (Lythraceae) represented new records for the State of Paraiba. The autochoric syndrome was the most representative, with 51.5 % of the recorded species; the anemochory was the second most representative syndrome with 26.7 % of the species; and finally the zoochory, representing 22.3 % of the species. The floristic similarity dendrogram showed the formation of three well-defined groups, whose area with the highest value (J = 33.2) is located in a Caatinga region called Cariri Paraibano, while the lowest value observed (J = 5.2), occurred in a settled area in two geomorphological units, a crystalline complex and a plateau region. These results may be due to the varying topographic conditions and edaphic heterogeneity arising from the specific geological formation of the region. These results yet demonstrate that, in rocky outcrops, abiotic syndromes represent an effective dispersion of its diaspores, favoring plant specie's colonization dynamics.
Los estudios florísticos proveen información valiosa sobre la riqueza de especies de una región, y son particularmente importantes si estas áreas pertenecen a ambientes menos estudiados como los afloramientos rocosos. Un aspecto importante para la colonización de especies incluye los mecanismos de dispersión de diáspo-ras en cada comunidad; estos son esenciales para entender la estructura, dinámica y el proceso de regeneración, constituyendo una herramienta importante para la conservación. En este estudio se realizó un levantamiento florístico de un afloramiento de granito-gneis con el objetivo de ampliar el conocimiento sobre la diversidad vegetal a través del análisis de similitud florística con la de otros afloramientos rocosos del nordeste brasileño y la detección de los síndromes de dispersión de las especies muestreadas en un área de la región semiárida de Brasil. Los trabajos de campo incluyeron recolección y observación de los materiales vegetales 'i" loco'durante el periodo de 12 meses. Un total de 161 especies pertenecientes a 127 géneros y 50 familias de angiospermas fueron registradas. Fabaceae, Asteraceae y Convolvulaceae fueron las familias más representativas en número de especies. Allophylus quercifolius(Mart.) Radlk. (Sapindaceae) y Lafoensia pacariA.St.-Hil. (Lythraceae) representan nuevas citas para el estado de Paraíba. El síndrome autocórico fue lo más representativo, con 51 % de las especies registradas; la anemocoria el segundo, con 27.7 % de las especies y finalmente la zoocoria, representando el 22.3 %. El dendrograma de similitud florística ha demostrado la formación de tres grupos bien definidos, cuya área con mayor índice (J = 33.2) está ubicada en una región de Caatinga llamada Cariri Paraibano mientras el menor índice "in loco"(J = 5.2) ocurrió en un área ubicada en dos unidades geomorfológicas: un complejo cristalino y una región de Planalto. Estos resultados se deben a las variables condiciones topográficas y a la heterogeneidad edáfica proveniente de la formación geológica especifica de la región. Estos resultados demuestran todavía que en afloramientos rocosos, síndromes abióticos representan una dispersión eficaz de sus diásporas, favoreciendo la dinámica de colonización de las especies vegetales.
Asunto(s)
Magnoliopsida/clasificación , Biodiversidad , Dispersión de Semillas/fisiología , Magnoliopsida/fisiología , Brasil , Estaciones del Año , Especificidad de la EspecieRESUMEN
RESUMO Este trabalho teve como objetivo conhecer a diversidade vegetal de uma área de Cerrado em Prudente de Morais, MG, bem como suas indicações medicinais. Foram feitas nove excursões à reserva da Fazenda Experimental Santa Rita da Empresa de Pesquisa Agropecuária de Minas Gerais (FESR/EPAMIG) (19°26’20”’ S e 44°09’15”’ W). O material vegetal coletado foi herborizado, identificado e incorporado ao acervo do Herbário PAMG/EPAMIG. O sistema de classificação utilizado foi o APG III. Após a identificação, realizou-se uma pesquisa bibliográfica buscando dados sobre a utilização medicinal das espécies. Coletaram-se 108 espécies pertencentes a 47 famílias. As famílias mais representativas foram: Fabaceae, com 16 espécies, Myrtaceae com sete espécies, Asteraceae e Rubiaceae com seis espécies cada, Malpighiaceae e Solanaceae com cinco espécies cada, Erythroxylaceae, Euphorbiaceae e Vochysiaceae, com quatro espécies cada, Anacardiaceae, Apocynaceae, Lamiaceae e Sapindaceae com três espécies cada, Annonaceae, Arecaceae, Bignoniaceae, Celastraceae e Primulaceae com duas espécies cada. Vinte e nove famílias foram monoespecíficas. Das 108 espécies, 39 são árvores (36%), 43 arbustos (40%), seis subarbustos (5,5%), 14 lianas (13%) e seis são ervas (5,5%). Sessenta e seis (61%) espécies pertencentes a 39 famílias (83%) são utilizadas popularmente, para o tratamento de alguma doença. As famílias com maior número de espécies medicinais foram: Fabaceae com oito espécies; Rubiaceae com cinco espécies e Solanaceae com quatro espécies. As espécies que apresentaram mais finalidades terapêuticas foram: Brosimum gaudichaudii Trécul (Moraceae), Caryocar brasiliense Cambess. (Caryocaraceae), Cochlospermum regium (Mart. ex Schrank) Pilg. (Bixaceae), Croton urucurana Bail. (Euphorbiaceae), Gomphrena officinalis Mart. (Amaranthaceae), Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae), Lithrea molleoides (Vell.) Engl. (Anacardiaceae), Myracrodruon urundeuva Allemão (Anacardiaceae) e Randia. armata (Sw.) DC. (Rubiaceae). As finalidades terapêuticas que apresentaram maior número de espécies foram: tônico (15 spp., 22,7%), afecções do aparelho respiratório (13 spp., 19,6%), afecções da pele (12 spp., 18%) e febres (12 spp., 18%). O conhecimento tradicional sobre as plantas medicinais do cerrado deve ser mais investigado para que seja preservado, valorizado, e para que medidas conservacionistas sejam tomadas evitando que essas plantas desapareçam antes que sua utilização tradicional seja corroborada pela ciência.
ABSTRACT This study aimed to investigate the plant diversity of a Cerrado area in Prudente de Morais, MG, and its medicinal indications. Nine field trips were made to the reserve of Fazenda Experimental Santa Rita of the Empresa de Pesquisa Agropecuária de Minas Gerais (FESR/EPAMIG) (19°26’20” S and 44°09’15” W). The plant material collected was herborized, identified and incorporated into the collection of the Herbarium PAMG/EPAMIG. The classification system used was the APG III. After identification, we carried out a literature search to find data about the medical use of the species. 108 species were collected, belonging to 47 families. The most representative families were Fabaceae, with 16 species, Myrtaceae with seven species, Asteraceae and Rubiaceae with six species each, Malpighiaceae and Solanaceae with five species each, Erythroxylaceae, Euphorbiaceae and Vochysiaceae, with four species each, Anacardiaceae, Apocynaceae, Lamiaceae and Sapindaceae with three species each, Annonaceae, Arecaceae, Bignoniaceae, Celastraceae and Primulaceae with two species each. Twenty-nine families were monoespecific. From the 108 species, 39 are trees (36%), 43 are shrubs (40%), six are subshrubs (5.5%), 14 are climbing (13%) and six are herbs (5.5%). Sixty-six (61%) species belonging to 39 families (83%) are commonly used for the treatment of diseases. The families with the highest number of medicinal species were the Fabaceae with eight species; the Rubiaceae with five species and the Solanaceae with four species. The species showing more therapeutic purposes were: Brosimum gaudichaudii Trécul (Moraceae), Caryocar brasiliense Cambess. (Caryocaraceae), Cochlospermum regium (Mart. Ex Schrank) Pilg. (Bixaceae), Croton urucurana Bail. (Euphorbiaceae), Gomphrena officinalis Mart. (Amaranthaceae), Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae), Lithrea molleoides (Vell.) Engl. (Anacardiaceae), Myracrodruon urundeuva Allemão (Anacardiaceae) and Randia. armata (Sw.) DC. (Rubiaceae). The therapeutic purposes indicated by the highest number of species were: tonic (15 spp., 22.7%), diseases of the respiratory system (13 spp., 19.6%), skin affections (12 spp., 18%) and fever (12 spp., 18%). The traditional knowledge of medicinal plants of the Cerrado should be investigated further in order to be preserved and enhanced. In that sense, conservation measures should be taken for these plants do not disappear before their traditional use is supported by science.
Asunto(s)
Plantas Medicinales/clasificación , Magnoliopsida/clasificación , Pradera , Etnofarmacología/métodos , BiodiversidadRESUMEN
Los bosques sobre arena blanca, aunque bajo en nutrientes, se caracterizan por presentar no solo varias especies endémicas sino también varias especies monodominantes. En general, las plantas en este tipo de bosque presentan fustes notoriamente delgados. El objetivo del presente trabajo fue elaborar una clave dicotómica paralela para la identificación de las especies de Angiospermas arbóreas de los bosques sobre arena blanca de la Reserva Nacional Allpahuayo Mishana, Loreto, Perú. Para la elaboración de la lista de especies que ocurren en los bosques sobre arena blanca se hizo una revisión bibliográfica. Se encontraron 219 especies de Angiospermas, las especies con mayor porcentaje de individuos fueron: Pachira brevipes (26.27%), Caraipa utilis (17.90%), Dicymbe uaiparuensis (13.27%), Dendropanax umbellatus (3.28%), Sloanea spathulata (2.52%), Ternstroemia klugiana (2.30%), Haploclathra cordata (2.28%), Parkia igneiflora (1.20%), Emmotum floribundum (1.06%), Ravenia biramosa (1.04%) entre otras. La mayoría de las especies de los bosques sobre arena blanca pueden ser diferenciadas utilizando características de los tallos, ramas y hojas. Esta clave es de mucha utilidad para el desarrollo de inventarios florísticos y otros proyectos afines en los bosques sobre arena blanca de la Reserva Nacional Allpahuayo Mishana.
White sand forests, although low in nutrients, are characterized not only by several endemic species of plants but also by several monodominant species. In general, plants in this forest have noticeably thin stems. The aim of this work was to elaborate a parallel dichotomous key for the identification of Angiosperm tree species occurring on white sand forests at the Allpahuayo Mishana National Reserve, Loreto, Peru. We compiled a list of species from several publications in order to have the most comprehensive list of species that occur on white sand forest. We found 219 species of Angiosperm, the more abundant species were Pachira brevipes (26.27%), Caraipa utilis (17.90%), Dicymbe uaiparuensis (13.27%), Dendropanax umbellatus (3.28%), Sloanea spathulata (2.52%), Ternstroemia klugiana (2.30%), Haploclathra cordata (2.28%), Parkia igneiflora (1.20%), Emmotum floribundum (1.06%), Ravenia biramosa (1.04%) among others. Most species of white sand forests can be distinguished using characteristics of stems, branches and leaves. This key is very useful for the development of floristic inventories and related projects on white sand forests from Allpahuayo Mishana National Reserve.
Asunto(s)
Flora , Magnoliopsida/clasificación , Perú , Árboles/clasificaciónRESUMEN
Tropical Vochysiaceae includes mainly trees, and also shrubs and subshrubs. Three genera and seven species are present in the Brazilian state of Santa Catarina. The pollen morphology of six species of trees, belonging to three genera of the Vochysiaceae A. St-Hil. family, was studied. Herbaria samples were obtained, processed and treated by standard methods. The pollen grain morphology of Callisthene, Qualea and Vochysia is distinct. Medium sized pollen grains occur in Vochysia species, and small ones in Callisthene and Qualea. Specific characteristics were considered at species level [C. castellanosii H. F. Martins, C. kuhlmannii H. F.Martins, Qualea cordata Spreng var. cordata, Q. cryptantha (Spreng) Warm. var. cryptantha, Vochysia magnifica Warm. and V. tucanorum Mart.]. The presence of a fastigium (vestibulum) and a thin space devoid of nexine fixing the boundary of the apertural area is characteristic of Qualea and Vochysia species only. Rev. Biol. Trop. 62 (3): 1209-1215. Epub 2014 September 01.
Las Vochysiaceae tropicales incluyen principalmente árboles, arbustos y subarbustos. Tres géneros y siete especies están presentes en el estado brasileño de Santa Catarina. La morfología del polen de las seis especies de árboles, pertenecientes a tres géneros de la Vochysiaceae A. St.- Hil . familia, fue considerado en el presente trabajo. La morfología de los granos de polen de Callisthene Mart., Qualea Aubl. y Vochysia (Aubl.) Juss. es distinta. Los granos de polen de tamaño medio se producen en las especies de Vochysia y pequeños en Callisthene y Qualea. Características particulares fueron considerados a nivel de especie [C. castellanosii H.F. Martins, C. kuhlmannii H.F. Martins, Qualea cordata Spreng var. cordata, Q. cryptantha (Spreng) Warm. var. cryptantha, Vochysia magnifica Warm. and V. tucanorum Mart.]. La presencia de un fastigium (vestibulum) y de un espacio delgado que carece de nexina limita la zona apertural y es característica solo de las especies de Qualea y Vochysia.
Asunto(s)
Magnoliopsida/anatomía & histología , Polen/anatomía & histología , Magnoliopsida/clasificación , Brasil , Polen/clasificación , ÁrbolesRESUMEN
To describe plant phenological patterns and correlate functioning for the quantity and quality of resources available for the pollinator, it is crucial to understand the temporal dynamics of biological communities. In this way, the pollination syndromes of 46 species with different growth habits (trees, shrubs, herbs, and vines) were examined in an area of Caatinga vegetation, northeastern Brazil (7° 28′ 45″ S and 36° 54′ 18″ W), during two years. Flowering was monitored monthly in all the species, over two years (from January 2003 to December 2004). Pollination syndromes were characterised based on floral traits such as size, colour, morphology, symmetry, floral resources, as well as on direct visual observation of floral visitors on focal plants and published information. We observed differences among the plant growth habits with respect to floral traits, types of resources offered, and floral syndromes. The flowering periods of the species varied among floral syndrome groups. The majority of the melittophilous species flowered during the rainy season in the two study years, while the species of the other pollination syndroms flowered at the end of the dry season. An asynchrony of flowering was noted among the chiropterophilous species, while the phalenophilous group concentrated during the rainy season. The overall availability of floral resources was different during the rainy and the dry seasons, and also it varied among plants with different growth habits. The availability of oil-flowers coincided with the period of low nectar availability. We observed a relationship between the temporal distribution of the pollination syndromes and the availability of floral resources among each growth habits in this tropical ecosystem. Resource allocation in seasonal environments, such as the Caatinga, can function as a strategy for maintaining pollinators, facilitating therefore the reproductive success of plant species. The availability of floral resources during all the year, specially in seasonal environments such as the Caatinga, may function as a strategy to maintain pollinator populations ensuring the reproductive success of the plants.
Descrever o padrão fenológico das plantas e correlacionar com a quantidade e qualidade dos recursos disponíveis para os polinizadores é fundamental para entender a dinâmica temporal das comunidades biológicas. Neste sentido, foram estudadas as síndromes de polinização de 46 espécies com diferentes hábitos (árvores, arbustos, ervas, trepadeiras) em uma área de caatinga, no Cariri Paraibano no Nordeste do Brasil (7° 28′ 45″ S e 36° 54′ 18″ W) durante dois anos. Para as diferentes espécies foi acompanhado o período de floração, sendo destacada a fase de início e o pico. As síndromes de polinização foram caracterizadas com base nos atributos florais, como tamanho, cor, morfologia, simetria, tipo de recurso, bem como a partir de observações visuais diretas dos visitantes florais em plantas focais e informações de literatura. Foram encontradas diferenças entre os hábitos, relacionadas aos distintos atributos florais, tipo de recurso e síndrome floral. O período de floração das espécies mostrou-se distinto entre os diferentes tipos de síndromes. A maioria das espécies melitófilas floresceu na estação úmida, enquanto as demais no final da estação seca, nos dois anos de estudo. Foi observada assincronia na floração das espécies quiropterófilas e concentração entre as esfingófilas na estação úmida. A disponibilidade de recursos florais apresentou diferenças entre as estações seca e chuvosa, diferindo também entre os hábitos. A oferta de flores de óleo coincidiu com o período de menor disponibilidade de néctar. Foi observada relação entre a distribuição temporal das diferentes síndromes de polinização, juntamente com a disponibilidade dos recursos florais, nos diferentes hábitos para este ecossistema tropical. A alocação de recursos em ambientes sazonais, como a Caatinga estudada, pode funcionar como uma estratégia para manutenção de polinizadores, facilitando, portanto o sucesso reprodutivo das espécies vegetais.
Asunto(s)
Magnoliopsida/fisiología , Flores/fisiología , Polinización/fisiología , Magnoliopsida/clasificación , Brasil , Estaciones del Año , Especificidad de la EspecieRESUMEN
High species richness of tropical riparian trees influences the diversity of organic detritus entering streams, creating temporal variability in litter quantity and quality. We examined the influence of species of riparian plants and macroinvertebrate exclusion on leaf-litter breakdown in a headwater stream in the Luquillo Mountains of Puerto Rico. Leaf litter of Dacryodes excelsa (Burseraceae), Guarea guidonia (Meliaceae), Cecropia scheberiana (Moraceae), Manilkara bidentata (Sapotaceae), and Prestoea acuminata (Palmae) were incubated in litter bags in a pool of Quebrada Prieta. Fine mesh bags were used to exclude macroinvertebrates during leaf breakdown, and coarse mesh bags allowed access to decapod crustaceans (juvenile shrimps and crabs) and aquatic insects (mainly mayflies, chironomids, and caddisflies). D. excelsa and G. guidonia (in coarse- and fine-mesh bags) had significantly higher breakdown rates than C. scheberiana, M. bidentata, and P. acuminata. Breakdown rates were significantly faster in coarse-mesh bag treatments for all leaf types, thus indicating a positive contribution of macroinvertebrates in leaf litter breakdown in this headwater stream. After 42 days of incubation, densities of total invertebrates, mayflies and caddisflies, were higher in bags with D. excelsa and G. guidonia, and lower in P. acuminata, C. scheberiana y M. bidentata. Decay rates were positively correlated to insect densities. Our study highlights the importance of leaf identity and macroinvertebrate exclusion on the process of leaf litter breakdown in tropical headwater streams. Rev. Biol. Trop. 62 (Suppl. 2): 143-154. Epub 2014 April 01.
La gran variedad de especies vegetales junto a los ríos tropicales afecta la diversidad de detritos orgánicos que llegan a los arroyos, creando variaciones temporales en cantidad y calidad de hojarasca. Examinamos la influencia de las especies vegetales y de la exclusión de macroinvertebrados sobre la descomposición de hojarasca en la parte alta de un arroyo en las montañas Luquillo de Puerto Rico. Incubamos hojarasca de Dacryodes excelsa (Burseraceae), Guarea guidonia (Meliaceae), Cecropia scheberiana (Moraceae), Manilkara bidentata (Sapotaceae) y Prestoea acuminata (Palmae) en bolsas descomposición que colocamos en una poza de Quebrada Prieta. Usamos bolsas de malla fina para excluir los macroinvertebrados y de malla gruesa para permitir la entrada a crustáceos decápodos (camarones y cangrejos jóvenes) e insectos acuáticos (principalmente efemerópteros, quironómidos y tricópteros). D. excelsa y G. guidonia (en ambos tipos de malla) tuvieron tasas de descomposición más altas que C. scheberiana, M. bidentata y P. acuminata. La descomposición fue más rápida para todas las especies de hoja con la malla gruesa, resaltando el papel de los descomponedores en este hábitat. Tras 42 días de esta incubación, las densidades totales de invertebrados, efemerópteros y tricópteros fueron mayores en las bolsas con hojas de D. excelsa y G. guidonia, e inferiores en P. acuminata, C. scheberiana y M. bidentata. A mayor densidad de insectos hubo mayor tasa de descomposición. Nuestros resultados indican la importancia de la especie de las hojas y de la presencia de macroinvertebrados en el proceso de descomposición de hojarasca en partes altas de arroyos tropicales.
Asunto(s)
Animales , Magnoliopsida/metabolismo , Biodegradación Ambiental , Decápodos/fisiología , Invertebrados/fisiología , Hojas de la Planta/metabolismo , Magnoliopsida/clasificación , Decápodos/clasificación , Ecosistema , Invertebrados/clasificación , Puerto Rico , Ríos/química , Factores de TiempoRESUMEN
We analysed the germination of seeds after their passage through the digestive tract of small floodplain fishes. Samples were collected in five open flooded fields of the northern Pantanal in March 2011. All fishes were sacrificed and their intestinal contents were removed. The fecal material was weighed and stored at 4°C in a GF/C filter wrapped in aluminum foil. The material was then transferred to a receptacle containing sterilised soil from the sampling area. The fecal samples were kept in a germination chamber for 68 days and then transferred to a greenhouse for another 67 days. We collected a total of 45 fish species and 1014 individuals which produced a total amount of 32g of fresh fecal mass and 11 seedlings. We were able to identify six seedlings: two Banara arguta, two Steinchisma laxa, one Hymenachne amplexicaulis and one Luziola sp.. The fish species that produced samples with seedlings were Astyanax assuncionensis, Metynnis mola, Plesiolebias glaucopterus, Acestrorhyncus pantaneiro and Anadoras wendelli. With the exception of B. arguta the remaining plant species and all fish species were not known to be associated with the seed dispersal process of these plants. We found a ratio of 0.435 seedlings.g–1 of fresh fecal material, which is 100 times higher than the amount of seedlings encountered in fresh soil mass (92,974 grams) in seed bank studies conducted in the same study area. In particular, Astyanax assuncionensis and Metynnis mola were among the most frequent and most abundant fish taxa in the area. Together with the high seed concentration in the fish fecal material, this evidence allows us to conclude that such fish species may play an important role in seed dispersal in the herbaceous plants of the Pantanal.
Nós analisamos a germinação de sementes após a passagem pelo trato digestivo de peixes de pequeno porte da planície de inundação do Pantanal de Mato Grosso. As amostras foram retiradas de cinco campos inundáveis em março de 2011. Todos os peixes foram sacrificados e seus conteúdos intestinais removidos. O material fecal foi pesado e armazenado a 4°C em filtros GF/C envolvidos em papel alumínio. O material foi transferido para um recipiente contendo solo da região previamente esterilizado e regado diariamente. As amostras de fezes foram mantidas por 68 dias numa câmara de germinação e então mantidas por mais 67 dias na casa de vegetação. Coletamos 1014 indivíduos de peixes distribuídos em 45 espécies que produziram um total de 32g. de fezes e 11 plântulas das quais seis foram identificadas como Banara arguta (n=2), Steinchisma laxa (n=2), Hymenachne amplexicaulis (n=1) e Luziola sp. (n=1). As espécies de peixes que produziram amostras com germinações foram Astyanax assuncionensis, Metynnis mola, Plesiolebias glaucopterus, Acestrorhyncus pantaneiro e Anadoras wendelli. Esse é o primeiro relato que associa essas espécies de plantas e de peixes no processo de dispersão de sementes com exceção de B. arguta. Encontramos uma razão de 0,435 germinações.g–1 por massa úmida fecal, o que representa 100 vezes mais germinações do que o registrado por massa úmida de solo num estudo de banco de sementes de solo da mesma região. Em particular, Astyanax assuncionensis e Metynnis mola estão entre as espécies mais frequentes e abundantes da área de estudo. Considerando a alta concentração de germinações por massa de material fecal essa evidência nos permite sugerir que os peixes de pequeno porte da planície de inundação do Pantanal podem ter um efeito determinante na dispersão de herbáceas do Pantanal.
Asunto(s)
Animales , Magnoliopsida/clasificación , Peces/fisiología , Dispersión de Semillas , Magnoliopsida/crecimiento & desarrollo , Brasil , Ecosistema , Heces , Peces/clasificación , Contenido Digestivo , Estaciones del Año , HumedalesRESUMEN
The fragments of Abies guatemalensis forests in Western Guatemala are the reservoirs of plant species that have been poorly documented, missing the opportunity to expand the knowledge of the local flora and its use in conservation planning. To assess this, a floristic study was done in areas between 2 950-3 360masl in Western Guatemala between 2010-2011. Ten locations were sampled: in each a 500m² plot was surveyed, and plants were classified in four strata by plant height (0.05-30m). A total of 119 species, 92 genera and 50 families in four divisions were found. The families with more species were Asteraceae, Poaceae, Rosaceae, Lamiaceae, Apiaceae and Solanaceae, and the most abundant genera were Salvia, Alchemilla and Bidens. The number of species found by strata was: 33 (low herbaceous), 49 (high herbaceous), 30 (shrubs) and seven in the tree strata. Regarding geographical distribution, the biggest species group detected was from central Mexico to Central America with 67%, which compared to the forests of A. guatemalensis in central and Southern Mexico, showed high floristic affinity, especially at the family and genus level. However, even having families and genera in common in the general structure of the fir forests, their floristic particularities should be taken into account when making management and conservation plans, because these are influenced by soil, latitude and microclimate conditions.
Hay una carencia de información detallada sobre la composición y estructura de las comunidades montanas guatemaltecas. El objetivo del estudio fue contribuir al conocimiento de la flora de bosques de abeto (Abies guatemalensis), para esto se hizo el levantamiento florístico en bosques de abeto del occidente de Guatemala. Se encontraron 119 especies, 92 géneros, 50 familias en cuatro divisiones. Las familias más numerosas fueron: Asteraceae, Poaceae, Rosaceae, Lamiaceae, Apiaceae y Solanaceae y los géneros más abundantes Salvia, Alchemilla y Bidens. Las especies se ubicaron en cuatro estratos, 33 en el herbáceo inferior, 49 en el herbáceo superior, 30 en arbustos y siete en árboles. Se hace énfasis en la contribución del estudio al conocimiento de la flora de bosques de A. guatemalensis y la necesidad de otros similares en los demás bosques de esta especie, que sirva para fomentar su conocimiento y conservación. Se consideraron seis grupos de distribución geográfica, el principal es del centro de México a Centroamérica con 67% de especies. Se realiza una comparación fitogeográfica y de composición florística, con otras áreas de Abies de Guatemala y México. Se propone que a pesar de haber familias y géneros comunes, que proporcionan la estructura general entre los bosques de abeto, se deben considerar las particularidades florísticas de cada área, en el manejo y conservación influidas por suelo, latitud y microclima.
Asunto(s)
Abies , Magnoliopsida/clasificación , Ecosistema , Árboles , Biodiversidad , GuatemalaRESUMEN
The Lagoa do Peixe has its connection with the sea artificially opened every year at the end of winter. However, this management has been carried out without the evaluation of the impact of this opening in the aquatic biodiversity. This information is crucial for the management of the natural resources of the Lagoa do Peixe National Park, the unique Ramsar site in Southern Brazil. The following questions were analyzed: (1) Do richness and composition of aquatic macrophytes from Lagoa do Peixe floodplain varies temporarily according to the sandbar opening and closing? (2) Does the variation pattern of the macrophyte community changed according to the sandbar opening and closing? A set of eight sampling sites of 1ha were selected over the Lagoa do Peixe floodplain: four sites not influenced by the artificial sandbar opening and four sites influenced by this event, being two sites closer to the sandbar opening and the two sites distant to the sandbar opening. The samplings were carried out between November 2007 and October 2009. The results show that although the artificial sandbar breaching does not affect the aquatic macrophyte richness at the floodplain, it affects the dynamics of species composition. The hydrological variation related to this management can be the main factor of the continuous change in the species composition in the floodplain, especially in the Southern portion. In order to avoid impacts in the macrophyte conservation, the artificial sandbar opening should be considered carefully, since the area of study is one of the most important conservation units to wetland systems in Southern Brazil.
La Lagoa do Peixe, en el sur de Brasil, tiene conexión artificial con el mar, porque cada año, al final del invierno, se abre un canal con tractor. Sin embargo, esta práctica se ha levado a cabo sin la evaluación de los efectos de esta apertura en la biodiversidad acuática. Las siguientes preguntas fueron analizadas: (1) ¿Varían la riqueza y la composición de los macrófitos acuáticos de la llanura de inundación temporal de la Lagoa do Peixe según la apertura y el cierre del banco arena? (2) ¿Varía el patrón de la comunidad de macrófitos según la apertura y el cierre del banco de arena? Los resultados muestran que la eliminación artificial del banco de arena no afecta la riqueza de macrófitos acuáticos en la llanura de inundación, pero sí afecta la dinámica de la composición de especies. La variación hidrológica relacionada con la apertura puede ser el factor principal del cambio continuo en la composición de especies en la llanura de inundación, especialmente en la parte sur. Con el fin de evitar un impacto negativo en la conservación de macrófitos, la apertura del banco de arena debe considerase cuidadosamente.
Asunto(s)
Magnoliopsida/clasificación , Biodiversidad , Biomasa , Humedales , Brasil , Lagos , Dinámica Poblacional , Estaciones del AñoRESUMEN
Phytoremediation is an ecologically sound biotechnology directed to cleaning up contaminated soils. The study of tree species to treat petroleum contaminated soils is scarce; moreover, the combination of phytoremediation with bioaugmentation and biostimulation processes is also limited. Thus, this work evaluated the effects of the inoculation of Glomus intraradices, a bacterial consortium (M2BOS1-R2 and M2BOSI-F4) and Trichoderma viride, on the growth of Casuarina equisetifolia, fertilized with Floranid® or Triple 17, when sown in a diesel-contaminated soil (7 500mg/kg). The factorial experiment 2x5x3 included 30 treatments with 10 replicates in a completely randomized design under greenhouse conditions for 120 days. Diesel significantly diminished plant height, total biomass, and plant index quality (PIQ). Glomus or bacterial consortium significantly increased plant height, total biomass and PIQ when compared to the inoculation of the three microorganisms or to the control. Floranid had negative effects on plant growth and PIQ at diesel contamination. Fertilization with Triple 17 combined with the three microorganisms stimulated plant growth in the absence of diesel, whereas in the presence of this contaminant the treatments combining Triple 17 with the bacterial consortium or with Trichoderma had better plant growth and PIQ. Mycorrhizal colonization was inhibited due to diesel contamination, and especially when Floranid was applied. The fertilizer Triple 17 (biostimulation) combined with the beneficial microorganisms (bioaugmentation) improved growth responses of C. equisetifolia in diesel-contaminated soil.
La fitorremediación es una biotecnología ecológicamente racional que está dirigida a la limpieza de suelos contaminados; sin embargo, el estudio de especies arbóreas para la fitorremediación de suelos con hidrocarburos del petróleo es limitado. Más aún, la combinación de la fitorremediación con procesos de bioaumentación y bioestimulación es también limitada. Por lo anterior, este estudio evaluó el efecto de la inoculación de Glomus intraradices, un consorcio bacteriano (M2BOS1-R2 y M2BOSI-F4) y Trichoderma viride en el crecimiento de plantas de Casuarina equisetifolia L. fertilizadas con Floranid® o Triple 17, en suelo contaminado con diésel (7 500mg/kg). El experimento factorial 2x5x3 incluyó 30 tratamientos y 10 repeticiones, distribuidos completamente al azar en invernadero, durante 120 días. El diésel disminuyó significativamente la altura, la biomasa total y el índice de calidad (ICP) de planta. Glomus o las bacterias aumentaron significativamente la altura, la biomasa seca total y el ICP con respecto al tratamiento sin inocular o con la triple inoculación. El Floranid redujo el crecimiento vegetal y el ICP, en presencia de diésel. El Triple 17 combinado con los tres microorganismos produjo mayor crecimiento vegetal en ausencia de contaminación, pero en presencia de diésel, el Triple 17 combinado con bacterias o con Trichoderma, estimuló la biomasa seca total y el ICP. La colonización micorrízica fue inhibida por el diesel, especialmente con la fertilización del Floranid. El Triple 17 (bioestimulación) combinado con los microorganismos (bioaumentación), favoreció el crecimiento de Casuarina en suelo contaminado con diésel.
Asunto(s)
Magnoliopsida/metabolismo , Biotecnología/métodos , Descontaminación/métodos , Petróleo/metabolismo , Contaminantes del Suelo/metabolismo , Magnoliopsida/clasificación , Biodegradación Ambiental , FertilizantesRESUMEN
Studies on Neotropical aquatic macrophytes have increased in recent decades, however species richness in wetlands of South America is far from being fully known. In addition, studies having an ecological approach are scarce in the Pantanal. Rapid assessments are essential for gaining knowledge of the biodiversity in the region. This study was performed in five sites of the Baía do Castelo, the western border of the Brazilian Pantanal, which included wild-rice patches, floating mats and floating meadows. At each site, plots of 0.5 × 0.5 m were set (n = 137), species of aquatic macrophytes were identified, their coverage was measured and the plot depth was estimated. We recorded 57 species in 26 families, of which Poaceae was the richest. The most frequent and abundant species was Commelina schomburgkiana; the second most frequent was Oryza latifolia,followed by Leersia hexandra, Enydra radicans and Pityrogramma calomelanos. The latter species was second in cover, followed by Pontederia rotundifolia, Eichhornia azurea, E. crassipes and Enydra radicans. These five species and C. schomburgkiana (the most abundant) together represent more than half of the coverage on the lake. Pontederia rotundifolia, Ludwigia helminthorrhiza, Pistia stratiotes, E. azurea, E. crassipes, Enydra radicans and Panicum elephantipes were strongly associated with deeper areas, while Oryza latifolia, Leersia hexandra and Salvinia auriculata were prevalent in shallow areas. Pityrogramma calomelanos, Ludwigia nervosa, Ipomoea alba, Cayaponia podantha, Polygonum acuminatum, Rhynchanthera novemnervia and Ludwigia leptocarpa were highly correlated with floating meadows. The structure of the habitat, natural dynamics and zonation of aquatic vegetation in the Baía do Castelo seems to be influenced by a variation in water levels, which promotes spatial segregation, most likely due to competition and/habitat preference.
Estudos sobre macrófitas aquáticas Neotropicais aumentaram nas últimas décadas; todavia, a riqueza de espécies em áreas úmidas da América do Sul está longe de ser plenamente conhecida. Além disso, trabalhos com abordagem ecológica são escassos no Pantanal. Por essa razão, levantamentos rápidos são essenciais para o conhecimento sobre a biodiversidade. Este estudo foi realizado em cinco pontos na Baía do Castelo, borda oeste do Pantanal brasileiro, os quais incluíram arrozal, camalotal e baceiros. Em cada ponto, foram estabelecidas parcelas 0.5 × 0.5 m (n = 137), onde foram identificadas as espécies de macrófitas aquáticas, estimada a cobertura e tomada a profundidade. Registramos 57 espécies distribuídas em 26 famílias, das quais a mais rica foi a Poaceae. A espécie mais frequente e abundante foi Commelina schomburgkiana; a segunda mais frequente foi Oryza latifolia, seguida por Leersia hexandra, Enydra radicans e Pityrogramma calomelanos. Essa última espécie foi a segunda com maior cobertura, seguida por Pontederia rotundifolia, Eichhornia azurea, E. crassipes e Enydra radicans. Essas cinco espécies juntamente com C. schomburgkiana (a mais abundante) representam mais da metade da cobertura na Baía do Castelo. Pontederia rotundifolia, Ludwigia helminthorrhiza, Pistia stratiotes, E. azurea, E. crassipes, E. radicans e Panicum elephantipes foram fortemente relacionadas às áreas mais profundas, enquanto Oryza latifolia, Leersia hexandra e Salvinia auriculata foram relacionadas a areas mais rasas. Pityrogramma calomelanos, Ludwigia nervosa, Ipomoea alba, Cayaponia podantha, Polygonum acuminatum, Rhynchanthera novemnervia e Ludwigia leptocarpa foram altamente correlacionadas com baceiros. A estrutura do habitat, a dinâmica natural e a zonação da vegetação aquática aparentam ser influenciadas pela variação nos níveis d'água na Baía do Castelo, os quais promovem a segregação espacial, provavelmente pela competição e/ou preferência por habitat.
Asunto(s)
Magnoliopsida/clasificación , Biodiversidad , Lagos , Brasil , Densidad de Población , Estaciones del AñoRESUMEN
RESUMEN: En el Jardín de Aclimatación de Plantas Nativas y Medicinales FCQUNA existen 34 "ysypo" nativas, de los cuales una especie pertenece a la clase Filicopsida (helechos), cinco a la clase Liliopsida (Monocotiledóneas) y 28 corresponden a la clase Magnoliopsida (Dicotiledóneas). T otalizan 17 familias y 24 géneros. Las tres familias más importantes según el número de especies son: Passifloraceae, Bignoniaceae, y Fabaceae. Entre ellas se destacan Herreria bonplandii Lecomte y H. montevidensis Klotzsch ex Griseb., especies que figura en la lista de especies amenazadas del Paraguay . La clave para la determinación de las especies de 'ysypo' nativas del Paraguay , permitirá contar con una herramienta que facilitará su correcta identificación. Palabras clave: clave, ysypo, nativa, Paraguay
Asunto(s)
Plantas Medicinales/clasificación , Magnoliopsida/clasificación , Paraguay , AclimataciónRESUMEN
Treatment with the usual antimalarial drugs, have induced parasite resistance, reinforcing the need to finding natural antimalarial components that would be found on plants from the forest. Therefore, we decided to look for these components in Costa Rican plants from a protected forest area. Fresh and dry extracts of roots, bark, leaves, flowers and fruits of 25 plants from a biological reserve in Costa Rica, Reserva Biológica Alberto Manuel Brenes (REBAMB), were studied in vitro for the presence of substances with antimalarial activity. By studying the inhibition of P. berghei schizogony, we assessed the antimalarial activity of several plant extracts: Aphelandra aurantiaca, A. tridentata (Acanthaceae); Xanthosoma undipes (Araceae); Iriartea deltoidea (Arecaceae); Neurolaena lobata (Asteraceae); Senna papillosa, Pterocarpus hayessi, Lonchocarpus pentaphyllus (Fabaceae); Nectandra membranacea, Persea povedae, Cinamomum chavarrianum (Lauraceae); Hampea appendiculata (Malvaceae); Ruagea glabra, Guarea glabra (Meliaceae); Psidium guajava (Myrtaceae); Bocconia frutescens (Papaveraceae); Piper friedrichsthalii (Piperaceae); Clematis dioica (Ranunculaceae); Prunus annularis (Rosaceae); Siparuna thecaphora (Siparunaceae); Solanum arboreum, Witheringia solanácea (Solanaceae); Ticodendrum incognitum (Ticodendraceae); Heliocarpus appendiculatus (Tiliaceae) and Myriocarpa longipes (Urticaceae). We used different parts of the plants as well as fresh and dried extracts for testing IC50. The solid content of the extracts ranged from 1-71.9μg/mL. The fresh extracts showed stronger activity than the dry ones. Since the plants showing the strongest antimalarial activity are very common in Central America, and some similar genera of these plants have shown positives results in South America, we considered important to present these findings for discussion. On the other hand, this is the first systematic study of this kind ever realized in a circumscribed and protected area of Costa Rica. Rev. Biol. Trop. 60 (2): 881-891. Epub 2012 June 01.
El tratamiento con las drogas antimaláricas de uso común han inducido resistencia por parte del parásito, lo que obliga a buscar en las plantas de los bosques, componentes naturales con actividad en contra de esta enfermedad. Por lo tanto, decidimos buscar dichos componentes en plantas de una Reserva Forestal de Costa Rica. Extractos tanto frescos como secos de raíz, corteza, hojas, flores y frutos, de 25 plantas de la Reserva Biológica Alberto Manuel Brenes (REBAMB), fueron estudiados in vitro en busca de sustancias con actividad antimalárica. Las plantas estudiadas fueron: Aphelandra aurantiaca, A. tridentata (Acanthaceae); Xanthosoma undipes (Araceae); Iriartea deltoidea (Arecaceae); Neurolaena lobata (Asteraceae); Senna papillosa, Pterocarpus hayessi, Lonchocarpus pentaphyllus (Fabaceae); Nectandra membranacea, Persea povedae, Cinamomum chavarrianum (Lauraceae); Hampea appendiculata (Malvaceae); Ruagea glabra, Guarea glabra (Meliaceae); Psidium guajava (Myrtaceae); Bocconia frutescens (Papaveraceae); Piper friedrichsthalii (Piperaceae); Clematis dioica (Ranunculaceae); Prunus annularis (Rosaceae); Siparuna thecaphora (Siparunaceae); Solanum arboreum, Witheringia solanacea (Solanaceae); Ticodendrum incognitum (Ticodendraceae); Heliocarpus appendiculatus (Tiliaceae) y Myriocarpa longipes (Urticaceae). Los extractos frescos y secos de las diferentes partes de las plantas fueron estudiadas y se determinó la IC50, el cual osciló entre 1-71.9mg/mL; los extractos frescos mostraron mayor actividad antimalárica. Las plantas que presentaron mayor actividad son muy comunes en Centroamérica y algunos géneros similares, aunque no las mismas especies, han sido encontrados positivos en América del Sur; por esta razón consideramos importante estos resultados como información y materia de discusión en este tema. Además este es el primer estudio sistemático de esta naturaleza realizado en un área boscosa circunscrita y protegida de Costa Rica.
Asunto(s)
Animales , Femenino , Masculino , Ratones , Magnoliopsida/química , Antimaláricos/farmacología , Extractos Vegetales/farmacología , Plasmodium berghei/efectos de los fármacos , Magnoliopsida/clasificación , Pruebas de Sensibilidad ParasitariaRESUMEN
Tropical forests vegetation and community research have tended to focus on the tree component, and limited attention has been paid to understory vegetation. Species diversity and composition of the understory of tropical seasonal rain forest were inventoried in a 625m² area (for sapling layer) and a 100m² area (for herb/seedling layer) in three 1ha plots. We found 3068 individuals belonging to 309 species, 192 genera and 89 families. The most important family as determined by the Family Importance Value (FIV) was Rubiaceae in both sapling and herb/seedling layers. In terms of Importance Value Index (IVI), the shrub Mycetia gracilis (Rubiaceae) was the most important species in the sapling layer and the pteridophyte Selaginella delicatula (Selaginellaceae) was the most ecological significant species in the herb/seedling layer. Much more vascular plant species were registered in the understory than in the tree layer totaled among the three plots. The species diversity did not differ significantly among the tree layer, sapling layer and herb/seedling layer. Given that we still know little about the understory plant community for growth forms other than trees, the results from the present study indicate that more attention should be paid to the understory vegetation during the decision-making process for biodiversity conservation in the tropical forests. Rev. Biol. Trop. 59 (1): 455-463. Epub 2011 March 01.
La investigación de la vegetación y las comunidades presentes en bosques tropicales han tendido a centrarse en el componente arbóreo, y se ha prestado poca atención a la vegetación del sotobosque. La diversidad de especies y la composición del sotobosque de los bosques tropicales estacionales fueron inventariados en un área de 625m² (identificación de árboles jóvenes) y un área de 100 m² (capa de plántulas/hierbas) en tres parcelas de 1 ha. Hemos encontrado 3 068 individuos pertenecientes a 309 especies, 192 géneros y 89 familias. La familia más importante según lo determinado por el Valor de Importancia por Familia (FIVFamily Important Value) fue Rubiaceae, tanto en la capa de árboles jóvenes como para la de plántulas y hierbas. En términos del Índice de Valor de Importancia (IVI-Importance Value Index), el arbusto Mycetia gracilis (Rubiaceae) fue la especie más importante en la capa de árboles jóvenes y la pteridofitas Selaginella delicatula (Selaginellaceae) fue la especie más importante ecológica en la capa de plántulas e hierbas. Mucho más especies de plantas vasculares fueron inventariadas en el sotobosque que en el estrato arbóreo de las tres parcelas juntas. La diversidad de especies no difirió significativamente entre la capa de árboles, la de árboles jóvenes y la de plántulas y de hierbas. Teniendo en cuenta que aún sabemos poco sobre la comunidad de plantas del sotobosque, los resultados del presente estudio indican que debe prestarse más atención a la vegetación del sotobosque durante el proceso de toma de decisiones para la conservación de la biodiversidad en los bosques tropicales.
Asunto(s)
Magnoliopsida/clasificación , Biodiversidad , Biomasa , Árboles , China , Estaciones del Año , Clima TropicalRESUMEN
Neotropical aquatic ecosystems have a rich aquatic flora. In this report, we have isted the aquatic flora of various habitats of the upper Paraná River floodplain by compiling data rom literature and records of our own continuous collections conducted during the period 2007-2009. Our main purposes were to assess the macrophyte richness in the Paraná floodplain, to compare it with other South American wetlands and to assess whether the number of species recorded in South American inventories has already reached an asymptote. We recorded a total of 153 species of macrophytes in the Upper Paraná River floodplain, belonging to 100 genera and 47 families. In our comparative analysis, a clear floristic split from other South American wetlands was shown, except for the Pantanal, which is the closest wetland to the Paraná floodplain and, therefore, could be considered a floristic extension of the Pantanal. The species accumulation curve provides evidence that sampling efforts should be reinforced in order to compile a macrophyte flora census for South America. The high dissimilarity among South American wetlands, together with the lack of an asymptote in our species accumulation curve, indicates that the sampling effort needs to be increased to account for the actual species richness of macrophytes in this region. Rev. Biol. Trop. 59 (2): 541-556. Epub 2011 June 01.
Los ecosistemas acuáticos neotropicales tienen una rica flora acuática. En este informe, hemos hecho una lista de la flora acuática de diversos hábitats de la alta planicie de inundación del río Paraná mediante la compilación de datos de la literatura y los registros de nuestras colecciones propias realizadas durante el período 2007-2009. Nuestros principales objetivos fueron evaluar la riqueza de macrófitos en la llanura aluvial del Paraná, para compararlo con otros humedales de América del Sur y evaluar si el número de especies registradas en los inventarios suramericanos ya han alcanzado una asíntota. Se registraron un total de 153 especies de macrófitas en la llanura de inundación del Río Alto Paraná, pertenecientes a 100 géneros y 47 familias. En nuestro análisis comparativo, se mostró una clara división florística de otros humedales de América del Sur, con excepción del Pantanal, que es el más cercano a los humedales de la planicie de inundación del Paraná y, por tanto, podría considerarse una extensión florística del Pantanal. La curva de acumulación de especies demuestra que los esfuerzos de muestreo deben ser reforzados con el fin de elaborar un censo de la flora de acrófitos para América del Sur. La alta disimilitud entre los humedales de América del Sur, junto con la falta de una asíntota en nuestra curva de acumulación de especies, indica que el esfuerzo de muestreo debe ser mayor para dar cuenta de la riqueza real de las especies de acrófitos en esta región.