Phenological diversity, seasonality and leaf longevity may affect leaf habits, reflecting plant responses to environmental conditions. Maprounea guianensis Aubl. is a widespread species in Brazil that is associated with different forest types. We investigated how phenological diversity, seasonality and leaf longevity affect leaf habits of its populations growing in humid and dry forests in the Chapada Diamantina mountains. We made monthly observations of leaf budding and fall in 62 individual trees between 2004 and 2012 (84 months), estimating leaf longevity based on phenophase evaluations. We made use of circular statistics, cross correlations and the Shannon–Wiener Index to evaluate our data. There was little variation in rainfall distribution between the study years, although water availability differed at each site. Phenophase seasonality was found to be negatively correlated with rainfall but positively correlated with photoperiod. Low phenological diversity was observed within each site, but not between sites, and leaf longevity was reduced in the dry forest. Although macroclimatic conditions were similar throughout the range of occurrence of M. guianensis in the region, we found that phenological behaviour and leaf longevity differed according to micro-site differences, demonstrating the plasticity of the species, which may favour its occupation of different environments.

Understanding pollen germination is of great importance for breeding and conservation. We present a protocol for evaluating culture media for germination of pollen of Elaeis guineensis. Samples were collected in the municipality of Nilo Pec ßanha (State of Bahia, Brazil). A solution of aniline blue in lactophenol was used to determine viability of pollen grains. Two alternative culture media to evaluate germination rates of pollen grains were tested: M1, Brewbaker and Kwack medium; and M2, BCa medium, with addition of boron and calcium. Both media were used with 20% sucrose at pH 6.5. The pollen grains were dried at room temperature in silica gel for 4 h and later placed on slides containing culture media, kept in a Petri dish with filter paper wetted with distilled water and stored in chamber at 30°C for 24 h. The greatest viability rate was 94% for fresh pollen grains. Highest germination rates were 26 and 64% for M1 and M2, respectively. There was no positive correlation between viability and germination for either M1 or M2 (Pearson's and Spearman's correlation, respectively). Dried pollen on BCa medium (M2) is useful for in vitro germination experiments of E. guineensis given appropriate concentration of sucrose and ions, pH, temperature and incubation time and in the absence of light.

Objetivo: Relatar a experiência do uso de tecnologias digitais, por um grupo tutorial do PET-Saúde Interprofissionalidade, durante o período de pandemia. Método: Foram priorizadas as plataformas de comunicação, WhatsApp e redes sociais para discussão, construção e divulgação do podcast sobre a interprofissionalidade no contexto da pandemia. Resultados: Todo esse processo ocorreu com base num roteiro que foi construído coletivamente, discutido, adaptado, respondido e revisado, com distribuição de tarefas entre os integrantes do grupo tutorial, e com base nos referenciais orientadores dessa tecnologia digital e dos princípios da educação interprofissional. Conclusão: O uso do podcast como tecnologia digital mostrou-se uma potente ferramenta para a produção e divulgação de conhecimento, possibilitando a continuidade da dinâmica do trabalho interprofissional mesmo num cenário de pandemia.

No abstract

The relationship between phenology and environmental factors is critical to understanding population dynamics in environmental gradients. We evaluated phenological variations in Croton heliotropiifolius Kunth in sites with contrasting water resource availability in caatinga, cerrado/caatinga transition, and cerrado in the Chapada Diamantina, Brazil. The phenophases of 81 individuals (n = 27 individuals/area) were recorded monthly for 12 months. Multiple regression, Spearman correlation, circular statistics, Shannon-Wiener diversity, and Morisita-Horn indices were used to test relationships between phenophases and abiotic factors, phenological seasonality, diversity, and similarities between the three populations. The vegetative behaviors in the study sites were distinct in terms of their intensity, seasonality, and synchrony; but reproductive phenophases maintained similar characteristics. Phenological events were positively related to rainfall and soil water availability. C. heliotropiifolius populations exhibited high levels of vegetative phenological diversity, except in the caatinga during the dry season. Reproductive phenological diversity varied along the studied period in the three sites, with higher reproductive than vegetative similarities among populations. Differences in soil types and rainfall volumes in the dry season, even at small distances, therefore make the savanna/caatinga gradient a suitable model for investigating phenological responses related to plant eco-hydrological strategies in seasonally tropical dry ecosystems.

No abstract

O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.

The wide distribution of Maprounea guianensis populations in contrasting environments (dry and humid forests) in the Chapada Diamantina, northeastern Brazil, can indicate the phenotypic plasticity of this species in relation to seasonal rainfall, drought regimes, and soil characteristics at different sites. Functional traits were measured in five individuals in each vegetation types. Water potential, succulence, thickness and density leaf, were evaluated during the dry and rainy periods; wood density and the saturated water content of the wood were evaluated in rainy period. Rainfall was monitored monthly for two years. The functional traits and the phenotypic plasticity indices (PPI) were submitted to analysis of variance. Our results demonstrated seasonal and spatial variations in plant functional traits. We found a low capacity for storing water in leaves and woody tissues, associated with soil properties and the seasonal rainfall/drought regimes, conditioning water potential variations that were greatest during the rainy season. Local environmental parameters influenced variations in the functional traits of M. guianensis populations, reflecting phenotypic plasticity. We highlight the connections between drought regimes and plant responses, demonstrating the importance of functional traits associated with water availability (especially water potential). Our study evidences the factors associated with the wide distribution of M. guianensis.