Fertility of Vriesea gigantea Gaud. (Bromeliaceae) in southern Brazil

摘要

Plant fertility is a central subject of many questions in plant evolutionary and conservation biology. Pollen availability, abioticnresources, and flowering pattern can limit fruit and seed production. Open pollination and pollen supplementation studies are usednto estimate any pollen limitation in natural populations. To study the impact of these factors on the reproductive success ofnVriesea gigantea, an epiphytic bromeliad in the Atlantic Rainforest in Brazil, its fertility in four natural populations in Itapua˜ StatenPark was assessed by considering plant and inflorescence size, flower production, fruit and seed set, flower and fruit set pattern,nand seed viability and germination rate. Supplemental pollination in adult plants was used to determine whether fruit production innV. gigantea is limited by reception of pollen. The results showed that V. gigantea has a high production of flowers, fruits, andnseeds. Seeds are highly viable in all populations, presenting an average germination rate of 94% (SE 6 3.5). Plants of V. giganteanfrom Itapua˜ State Park are highly fertile. The high proportion of fruit and seed set after manual hand pollination indicates that thenspecies is self-compatible. Pollination treatments showed evidence of pollinator limitation in the Itapua˜ State Park population.