Fenologia de floração e polinização de espécies ornitófilas na Serra da Bodoquena, Mato Grosso do Sul, Brasil




Hummingbirds are the major group of vertebrate pollinators in the neotropical region and, at these sites, plants pollinated by these birds can account for 2-15% of angiosperm species. The goals of this study were: (i) to analyze the flowering phenology and pollination of ornitophilous species in two environments (forest gallery and Semi-deciduous forest) of Serra da Bodoquena, and (ii) to describe the breeding system and to test fruit set under different intensities of pollination for Ruellia angustiflora, in gallery forest of Salobrinha river. The study was carried out between June 2005 and August 2006. Data on phenology, floral biology, nectar volume and concentration as well as on focal observations of floral visitors were carried out monthly in pre-marked individuals of all ornitophilous species recorded. Additionally, it was realized reproductive experiments and recorded fruit and seed set after one, two or three visits of hummingbirds on Ruellia angustiflora flowers. The studied community presented eight ornitophilous species and six hummingbird species. Acanthaceae was the most representative family between ornitophilous species, being the most frequent and the more important resource for hummingbirds. Ornitophilous species flowered yearround providing resources for the hummingbird community at the two studided habitats. Phaethornis pretrei was the major visitor of ornitophilous species, occurring year round at the study site and visiting flowers of all recorded plant species in a genuine manner. Results of manual cross-pollinations in Ruellia angustiflora suggest pollen limitation, because increasing fruit set occurred in response to increasing pollen loads. Although, it does not found a positive relation between number of visits and fruit and seed set for this species. According to results presented here, the only barrier that R. angustiflora seems to present to avoid auto-pollination is herkogamy.


floral resources annual flowering phaethornis phaethornis pretrei acanthaceae recursos florais acanthaceae ecologia hummingbird pollination

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