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Alien species can modify ecosystem functions and ecological processes in natural communities, and potentially become invasive. In the Brazilian Pampean grasslands, reports of changes in land use and invasions of alien plant species are becoming more frequent. This study aimed to investigate species composition and phylogenetic relationships between native and alien plants across four sites of Brazilian Pampean grasslands under distinct land uses (NOM: no agricultural management; GRZ: grazed pastures; AGR: agrarian crops; ROAD: roadside). The phylogenetic relationship between native and alien species was analyzed at two scales: inter-site (large scale) and intra-site (small scale). We found inter-site differences in phylogenetic diversity. Overall, across all sites we found random phylogenetic relationships among alien and native species. In the most disturbed site (ROAD) we found significant phylogenetic clustering among all species (alien and natives), while at the small scale, clustering was only found among natives. We conclude that clustering of phylogenetic relationships among alien and native species is only evident at small sampling scales in environments subject to high levels of disturbance (i.e., road sides) in the studied Pampean Grasslands, suggesting that environmental filtering plays an important role in local community assembly. Keywords: disturbance, land use, phylogenetic pattern, plant invasion, native communities

Las infecciones odontogénicas son condiciones clínicas graves y de ocurrencia relativamente común, caracterizadas por la rápida diseminación del proceso infeccioso a los tejidos adyacentes y espacios faciales de la región de la cabeza y cuello, pudiendo llevar al paciente a la muerte. Las infecciones que acontecen en la cavidad bucal son un problema de salud pública, pues u origen podría ser evitado con un tratamiento preventivo. Estas constituyen uno de los problemas más difíciles de tratamiento en odontología, sobre todo en nuestro país, donde grande parte de la población todavía posee índices de caries y enfermedad periodontal elevados, siendo la necrosis de la pulpa dental, resultante de caries profunda la principal causa, donde es creada una vía para que las bacterias penetren en los tejidos periapicales estableciendo una infección activa que irá a diseminarse preferencialmente a lo largo de líneas de menor resistencia. Estos procesos infecciosos pueden variar desde infecciones bien localizadas, que exigen un tratamiento mínimo, hasta infecciones de alta complejidad que envuelven un tratamiento multidisciplinario en ambiente hospitalario generando altos costos y sufrimiento al paciente. Así, compréndase que las medidas preventivas en salud pública son capaces de evitar el empeoramiento de procesos infecciosos en fase inicial y consecuentemente promueven una disminución de la morbilidad y mortalidad. The odontogenic infections are serious clinical conditions and relatively common occurrence, characterized by the rapid spread of the infectious process to adjacent tissues and fascial spaces of head and neck, which may lead the patient to death. Infections that affect the oral cavity are a public health problem, because their origin could be avoided with preventive treatment. These are one of the most difficult problems in dental treatment, especially in our country where much of the population still has rates higher caries and periodontal disease, with necrosis of the dental pulp resulting from the leading cause deep cavity, where it created a way to penetrate the bacteria in periapical tissues establishing an active infection that will spread preferentially along the lines of least resistance. These infectious processes can vary from highly localized infections that require minimal treatment, even infections that involve a highly complex multidisciplinary treatment in a hospital environment by generating high costs and suffering to the patient. Thus we understand that preventive measures in public health are able to avoid the aggravation of infectious processes in the initial phase and thus promote a decrease in morbidity and mortality.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Extrafloral nectaries (EFNs) are nectar-secreting glands found in various taxa of plants. These structures can attract different groups of animals which use the extrafloral nectar as a food source. Considering EFNs are structures commonly observed in the Brazilian Cerrado, the aim of this study was to identify the plant community (trees, lianas and scrub) bearing EFNs in an area of Cerrado. We also characterized morphological types of nectaries, location, phenology, productivity and arthropods that feed on extrafloral nectar. Twenty transects were established in order to survey the species. The species bearing EFNs were identified and characterized for its location and morphology each fifteen days and accompanied to evaluate its phenology over a year. Samples of extrafloral nectar and arthropods were held in different plant species. We recorded 26 species of EFN-bearing plants, distributed among trees, shrubs and lianas. The EFNs were found in different parts of plants, including vegetative and reproductive structures, or species that had the glands on both locations. Duo to the phenology aspects, we observed a pattern in which the majority of species presented secretory activity of EFNs in September and October, matching with the end of the dry season and the beginning of the rainy season. Thus, the strong seasonality in the Cerrado may be an important factor influencing these glands activities. The sugar concentration of nectar differed between species (H= 52.329; p

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Species of the genus Psychotria L. are common in the understory of tropical and subtropical forest formations. Most species are distylous with two floral morphs (thrum and pin) in the same population, however homostylous and monomorphic species are common. The objective of this work was to monitor the vegetative and reproductive phenology, as well as determine aspects of floral biology, with emphasis on floral morphometric and floral visitors of Psychotria leiocarpa Cham. & Schltdl., P. carthagenensis Jacq. e P. myriantha Muell. Arg. found in Seasonal Deciduous Forest fragment in Boca do Monte, Santa Maria, RS (53º54 W, 29º38 S). The phenological monitoring was performed every fortnight from August 2010 to August 2011. Were evaluated the vegetative phenophases (budding and leaf fall) and reproductive flowering (anthesis and bud) and fruiting (immature and mature fruit). Were observed during flowering period and duration of anthesis and floral visitors, and collected flowers for morphometric analysis and pollen viability. The three species have intraspecific synchrony in all phenophases. Leaf fall occurred throughout the year, but was more expressive P. leiocarpa in the months of autumn and winter, in other species restricted to a few leaves. The leaf emission was synchronic and occurred in spring, followed by the issue of buds. The bloom was like the annual intermediate for the three species and occurred between October and January. There was greater synchrony between P. leiocarpa and P. carthagenensis, P. myriantha has a slight delay in peak bloom. The fruiting is synchronic, and fruit maturation is gradual and long-term during the autumn and winter. The precipitation was not correlated with any of the phenophases. The highest correlations were obtained for immature fruit with ripe fruit temperature and with temperature and day length. In P. leiocarpa period of anthesis was from 5 to 17 hours. P. myriantha anthesis took several periods during the day, and lasts for 24 h. In P. carthagenensis anthesis occurred in two periods: between 5 to 18 hours and between 12 hours until the next morning. P. myriantha is homostílica. P. leiocarpa has the two floral morphs, reciprocal herkogamy and not isopletic. It has dimorphic traits auxiliary corolla length, size of the stigma lobes and the size of pollen grains, and higher in thrum flowers corolla diameter and number of pollen grains per anther, the higher pin flowers. P. carthagenensis has the two floral morphs, without reciprocal herkogamy and is not isopletic. Presented dimorphic traits auxiliary, length of stigma lobes and anther size, higher in thrum morph and diameter of the corolla in higher pin morpho. The floral visitors were insects, especially of the order Hymenoptera. Apis mellifera was the most frequent visitor in P. leiocarpa and P. myriantha. P. carthagenensis has native bees as the most frequent visitors Espécies do gênero Psychotria L. são comuns no sub-bosque das formações florestais tropicais e subtropicais. A maioria das espécies são distílicas, apresentando dois morfos florais (brevistilo e longistilo) em uma mesma população, contudo espécies homostílicas ou monomorficas são comuns. O objetivo deste trabalho foi o de acompanhar a fenologia vegetativa e reprodutiva, bem como determinar aspectos da biologia floral, com ênfase na morfometria floral, e os visitantes florais de Psychotria leiocarpa Cham. & Schltdl., P. carthagenensis Jacq. e P. myriantha Muell. Arg. encontradas em um fragmento de Floresta Estacional Decidual no distrito de Boca do Monte, Santa Maria, RS (53º54 W, 29º38 S). O acompanhamento fenológico foi quinzenal de agosto de 2010 a agosto de 2011. Foram observadas as fenofases vegetativas (queda foliar e brotamento) e reprodutivas de floração (botão e antese) e de frutificação (fruto imaturo e maduro). Durante a floração foram observados o período e duração da antese e visitantes florais, e realizadas coleta de flores para as análises morfométricas e de viabilidade polínica. As três espécies possuem sincronia intraespecífica em todas as fenofases. A queda foliar ocorreu durante todo o ano, mas foi mais expressiva em P. leiocarpa nos meses de outono e inverno, nas outras espécies restringiu-se a poucas folhas. O brotamento foi sincrônico entre as espécies e ocorreu nos meses de primavera, seguido da emissão de botões. A floração foi do tipo anual intermediária para as três espécies e ocorreu entre outubro e janeiro. Houve maior sincronia entre P. leiocarpa e P. carthagenensis, pois P. myriantha possui um pequeno atraso no pico de floração em relação às outras espécies. A frutificação é sincrônica, e a maturação dos frutos é gradual e de longa duração durante o outono e inverno. A precipitação não se correlacionou com nenhuma das fenofases. As maiores correlações foram obtidas para frutos imaturos com a temperatura e frutos maduros com a temperatura e comprimento do dia. A antese é diurna para as três espécies. Em P. leiocarpa, o período de antese foi entre 5h às 17 horas. P. myriantha teve vários períodos de antese durante o dia e duração de 24 horas. Em P. carthagenensis, a antese ocorreu em dois períodos: entre as 5h até 18h, e das 12h até a manhã do dia seguinte. P. myriantha é homostílica. P. leiocarpa possui os dois morfos florais, hercogamia recíproca e anisopletia. Apresentou características dimórficas auxiliares para comprimento da corola, tamanho dos lobos estigmáticos e no tamanho dos grãos de pólen, maior nas flores brevistilas e no diâmetro da corola e na quantidade de grãos de pólen por antera, maior nas flores longistilas. P. carthagenensis possui os dois morfos florais, sem hercogamia recíproca e é anisopletia. Apresentou características dimórficas auxiliares para comprimento dos lobos estigmáticos e tamanho da antera, maior no morfo brevistilo e diâmetro da corola, maior no morfo longistilo. Os visitantes florais foram insetos, principalmente da ordem Hymenoptera. Apis mellifera foi o visitante mais frequente em P. leiocarpa e P. myriantha, e P. carthagenensis apresenta abelhas nativas como os visitantes mais freqüentes.