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Information on plant phenological patterns aids in understanding the structure and functioning of ecosystems and support restoration projects in degraded areas. The aim of this study was to characterize the reproductive phenology of Avicennia germinans and Laguncularia racemosa in a mangrove forest in the Mamanguape River estuary in northeastern Brazil. The characterization was performed monthly from July 2016 to June 2017. We applied circular statistics to detect seasonal trends, calculated intra-specific synchrony, and performed regressions between the reproductive phenophases and the abiotic variables. Avicennia germinans exhibits seasonal responses to floral buds, flowers at anthesis, and fruit, with one reproductive episode per year (annual pattern). Laguncularia racemosa has no seasonal response, with one reproductive episode per year for floral buds (annual pattern) and two episodes for flowers at anthesis and fruits (subannual pattern). Reproductive phenophases of A. germinans exhibited higher intra-specific synchrony than L. racemosa. We provide evidence that temperature, solar radiation and rainfall are important drivers of the flowering rhythm in both species. In conclusion, the results of this study showed that the species exhibited different phenological responses, even though they were subjected to the same abiotic conditions. [ABSTRACT FROM AUTHOR]

Environmental characteristics are among the most important triggers and regulators of plant phenophases, so that the abiotic and biotic changes driven by habitat loss and fragmentation can result in alterations of plant phenological patterns. We investigated whether forest edge and interior have differences in phenological pattern of tree communities. We followed the reproductive phenologies of tree communities in seven forest fragments on a monthly basis for two years (in 200 m² edge and interior plots per fragment). We sampled a total of 0.28 ha of anthropic forest fragments, comprising 313 trees (180 in edge, 133 in interior) belonging to 103 species and 34 families. Our results evidenced reproductive phenological changes between edge and interior tree communities, with: (i) phenological activities differing temporally between the two habitats (edge and forest interior) in all tree communities; (ii) greater phenological intensity at the forest edge than in the forest interior among tree species common to both habitats; (iii) more tree species showed phenological activity at the forest edge in 2010 and interior in 2011, when considering only those exclusive to each habitat. Habitat fragmentation can therefore alter microenvironmental characteristics and influence biologic processes, including the reproductive phenologies of trees, through edge formation. [ABSTRACT FROM AUTHOR]

We analyzed the reproductive phenology of Ditassa burchellii and the influence of abiotic factors on the species phenophases. The study was conducted on individuals of a natural population from a semi-deciduous forest (Viçosa municipality, Minas Gerais state, southeastern Brazil). We quantified the activity and intensity indices of the following phenophases: flower bud, flower, immature fruit, and dehiscent fruit. To test for seasonality of phenophases, we analyzed each of them using Rayleigh test. We evaluated whether there was any association between abiotic variables (mean temperature, rainfall, and day length) and phenophases, in the month of occurrence and in the three months prior to the occurrence of each phenophase. The analyzed phenophases occurred mainly at the end of the rainy season and during the dry season, with overlapping periods, but with sequential peaks. The periods of occurrence of reproductive phenophases were similar to the ones in other climbing species and were mainly related to the dispersal mode. All phenophases were seasonal and were associated with at least one abiotic variable, either in the month of their occurrence or in the previous months. [ABSTRACT FROM AUTHOR]

Habitat fragmentation causes loss of biodiversity and may alter the reproductive patterns of the species. Phenological studies help understanding the cyclical events of vegetables and ecosystem dynamic. The objectives were to correlate reproductive events with climate variables, classify the species and the ecological succession and dispersal syndromes and compare the reproductive patterns between edge and interior. Were followed 155 individuals (96 edge and 59 interior), between August/2008 and August/2010 on monthly observations of reproductive phenophases using the activity index and intensity of Fournier. The production of flowers and fruits was observed over the years, with the fruiting longer duration than flowering. Reproductive events were more intense on the edge. Intensity Fournier was similar to that of phenophases activity index. The pattern community was "steady state" and continued, with the majority of annual species. Edge and interior had the same time of occurrence of phenophases, but the activity and the intensity of reproductive individuals were higher on edge. Pioneer species were more common in edge and secondary in interior. Zoochory was more frequent in both areas. Not significant correlations between the phenology and the climate were found, suggesting the action of other factors for induction of reproduction. [ABSTRACT FROM AUTHOR]

Floral visitation does not necessarily mean pollination, as several animals utilize floral resources without transferring pollen. Since pollinators and thieves can affect the reproduction, morphology and diversification of flowering plants, we here investigated if attributes of flowers and flowering of plant species collected in the central Brazilian vereda would predict the pollination (pollen seeking) or theft (pollen/nectar theft) during the visits. It was hypothesized that non specialized flowers would have a higher incidence of thievery, where as specialization, for example, the presence of large and medium flowers with long corolla, making it difficult to access nectar, would lead to increased pollination. As a result, four attributes were mainly associated with illegitimate visits, and in order of importance, they are size (small), quantity of flowers per plant (large), flowering time (< 10 months) and floral type (inconspicuous). The richest and most abundant visitor groups, including bees, flies and wasps, acted mainly as potential pollinators, while cockroaches, butterflies, beetles, ants and hemipterans acted as thieves. However, further studies are required to confirm that this pattern is repeated in other larger and more diverse communities, thus confirming the possible preference for floral thieves. [ABSTRACT FROM AUTHOR]