• Although the production of extranuptial nectar is a common strategy of indirect defence against herbivores among tropical plants, the presence of extranuptial nectaries in reproductive structures is rare, especially in ant-plants. This is because the presence of ants in reproductive organs can generate conflicts between the partners, as ants can inhibit the activity of pollinators or even castrate their host plants. Here we evaluate the hypothesis that the ant-plant Miconia tococa produces nectar in its petals which attracts ants and affects fruit set. • Floral buds were analysed using anatomical and histochemical techniques. The frequency and behaviour of floral visitors were recorded in field observations. Finally, an ant exclusion experiment was conducted to evaluate the effect of ant presence on fruit production. • The petals of M. tococa have a secretory epidermis that produces sugary compounds. Nectar production occurred during the floral bud stage and attracted 17 species of nonobligate ants (i.e. have a facultative association with ant-plants). Ants foraged only on floral buds, and thus did not affect the activity of pollinators in the neighbouring open flowers. The presence of ants in the inflorescences increased fruit production by 15%. • To our knowledge, the production of extranuptial nectar in the reproductive structures of a myrmecophyte is very rare, with few records in the literature. Although studies show conflicts between the partners in the ant-plant interaction, ants that forage on M. tococa floral buds protect the plant against floral herbivores without affecting bee pollination.
A regeneração natural em áreas de pastagem pode ser um processo muito lento, devido às diversas barreiras impostas por esse tipo de ambiente. Com o objetivo de investigar o potencial de regeneração natural das espécies lenhosas de uma área de pastagem abandonada, originalmente coberta por Floresta Estacional Decidual, buscou-se investigar os padrões florísticos da regeneração, delimitando dois microambientes: um abaixo da copa de árvores remanescentes isoladas e outro fora da projeção dessas mesmas copas. Em cada uma das 20 árvores remanescentes selecionadas, foram instaladas quatro parcelas de 4 m², sendo duas em cada microambiente. Nessas parcelas, foram inventariados todos os indivíduos lenhosos acima de 15 cm de altura e abaixo de 5 cm de diâmetro à altura do peito. No total, foram encontrados 245 indivíduos (224 abaixo da copa das árvores e 21 fora da copa), distribuídos em 51 espécies, 42 gêneros e 22 famílias botânicas. Os resultados apontam um grande potencial de regeneração para a área estudada, assim como corroboram com pesquisas que apontam o efeito facilitador de árvores remanescentes isoladas em pastagens.
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