Seed dispersal and population structure in Vriesea gigantea, a bromeliad from the Brazilian Atlantic Rainforest

Abstract

Seed dispersal, population structure and the mating system of plant species can have great consequences on the genetic structure of populations. Vriesea gigantea is a bromeliad from southeastern Brazil which is self-compatible and pollinator dependent for fruit set. Its populations are fertile in terms of the production of flowers, pollen, fruits and seeds. To assess the importance of seed supply for gene flow, colonization and distribution of adult individuals, the seed dispersal and population structure of V. gigantea were studied. Seeds are dispersed over short distances; most seeds land close to the mother plant. This pattern coincides with the reported aggregate distribution of bromeliad seedlings. Population structure results showed high seedling recruitment, because 51.3% developed into adults, although few juveniles reached this stage. This result is different from that for other bromeliad species from different habitat conditions. Seed dispersal and population structural patterns are consistent with previous molecular studies, revealing that V. gigantea populations are genetically structured, with low gene flow and a moderate outcrossing rate. Barbará T, Martinelli G, Palma-SilvaC, Fay MF, Mayo S, Lexer C. 2009. Genetic relationships and variation in reproductive strategies in four closely related bromeliads adapted to neotropical 'inselbergs': Alcantarea glaziouana, A. regina, A. geniculata and A. imperialis (Bromeliaceae). Annals of Botany 103: 65-77. Bennett BC. 1986. Patchiness, diversity, and abundance relationships of vascular epiphytes. Selbyana 9: 70-75. Bennett BC. 1991. Comparative biology of Neotropical epiphytic and saxicolous Tillandsia species: population structure. Journal of Tropical Biology 7: 361-371. Benzing DH. 1978. Germination and early establishment of Tillandsia circinnata Schlecht. (Bromeliaceae) on some of its hosts and other supports in southern Florida. Selbyana 2: 95-106. Benzing DH. 1981. Bark surfaces origin and maintenance of diversity among angiosperm epiphytes: a hypothesis. Selbyana 5: 248-255. Benzing DH. 1990. Vascular epiphytes: general biology and related biota. Cambridge: Cambridge University Press. Benzing DH. 2000. Bromeliaceae: profile of an adaptive radiation. Cambridge: Cambridge University Press.Bittencourt JVM, Sebbenn AM. 2007. Patterns of pollen and seed dispersal in a small, fragmented population of the wind-pollinated tree Araucaria angustifolia in southern Brazil. Heredity 99: 580-591. Borges LA, Sobrinho MS, Lopes AV. 2009. Phenology, pollination, and breeding system of the threatened tree Caesalpinia echinata Lam. (Fabaceae), and a review of studies on the reproductive biology in the genus. Flora 204: 111-130. Brown AHD. 1990. Genetic characterisation of plant mating system. In: Brown AHD, Clegg MT, Kahler AL, Weir BS, eds. Plant population genetics, breeding and genetic resources. Sunderland, MA: Sinauer Associates, 145-162. Bullock JM, Clarke RT. 2000. Long distance seed dispersal by wind: measuring and modeling the tail of the curve. Oecologia 124:...

Research Trails Affect the Abundance of an Epiphytic Tropical Bromeliad

“…The majority (>50%) of seeds of Vriesea gigantea are dispersed over distances of less than 1 m (Paggi et al . ). Seeds of Tillandsia deppeana are most often captured in seed traps at distances that correspond approximately to mean distances between host trees (García‐Franco & Rico‐Gray ).…”

Bromeliaceae in focus

“…The studies published by Paggi et al . () and Trindade Sampaio et al . () illustrate how studies on population ecology and inbreeding depression can affect evolution and diversification in wild populations of one focal species.…”

“…Evolutionary aspects of population ecological dynamics were published in five studies in this Virtual Issue (Paggi et al ., ; Trindade Sampaio et al ., ; Petit et al ., ; Loh et al ., ; Orozco‐Ibarrola et al ., ). Paggi et al .…”

“…Paggi et al . () studied seed dispersal in Vriesea gigantea Gaudich., an epiphytic species distributed across the Brazilian Atlantic rainforest. Like most members of subfamily Tillandsioideae, this species has plumose, wind‐dispersed seeds.…”

“…Evolutionary aspects of population ecological dynamics were published in five studies in this Virtual Issue (Paggi et al, 2010;Trindade Sampaio et al, species distributed across the Brazilian Atlantic rainforest. Like most members of subfamily Tillandsioideae, this species has plumose, wind-dispersed seeds.…”