artículo científico
Genetic diversity and reproductive biology of the dioecious and epiphytic bromeliad Aechmea mariae-reginae (Bromeliaceae) in Costa Rica: implications for its conservation
Fecha
2019Registro en:
VI-937-2016
0024-4074
1095-8339
10.1093/botlinnean/boz083
111-B6-210
Autor
Cascante Marín, Alfredo
Trejos Hernández, Christian
Madrigal Brenes, Ruth
Fuchs Castillo, Eric J.
Institución
Resumen
Ecological traits and pollination mode associated with dioecious sexual expression in plants are likely to influence
their reproductive success and levels of genetic diversity. Dioecy is an uncommon condition in Bromeliaceae. Currently,
there is limited information on the reproductive ecology and genetics of dioecious and epiphytic bromeliads. Therefore,
we studied the reproductive biology and genetic diversity of the epiphytic and dioecious bromeliad Aechmea mariaereginae in Costa Rica. Flowering of pistillate and staminate plants in one population showed high synchrony and
were pollinated by non-hermit hummingbirds. Sex ratio was biased to males (3.5:1). Fruit set was relatively high
(68%) but there was high female reproductive variance (C. V. = 59.7%). The species is capable of parthenocarpic fruit
production. Using eight nuclear microsatellite markers and six populations, we found moderate to high levels of
genetic variation (HE = 0.571–0.726). Populations showed significant genetic structure (G'ST = 0.385) and Bayesian
population assignment grouped them into lowland and montane clusters. Isolated montane populations had slightly
lower genetic diversity probably due to lower effective population size caused by biased sex ratios and recent
habitat fragmentation that limits long-distance pollinator movements and results in isolation by distance. If habitat
fragmentation and isolation persist, populations in montane habitats may be at higher risk of decline and extinction