Reproductive Biology of the Epiphytic Bromeliad Werauhia gladioliflora in a Premontane Tropical Forest

Abstract

The floral phenology, fruit and seed production, and self-compatibility of Werauhia gladioliflora, an epiphytic bromeliad with a wide distribution, were studied in a premontane forest in the Monteverde area in Costa Rica. The species presents the pollination syndrome of chiropterophily, and it is visited by the small bats Hylonycteris underwoodi and Glossophaga commissarisi (Glossophaginae). The population flowering period extended from October to early December (end of rainy season) and seed dispersal occurred from February to April (dry season). Most plants opened a single flower per night, either every day or at one-day intervals during the flowering period. In natural conditions, the average fruit set amounted to almost half of the potential output, but individual fecundity (number of seeds) remained high. Seed number per fruit and germination capacity after artificial selfing and out-crossing treatments did not differ from natural pollination conditions. Werauhia gladioliflora exhibited high levels of autonomous self-pollination and self-compatibility at the individual and population level, characters associated with the epiphytic habitat. These reproductive traits are also associated with early colonizer species, yet life history traits, such as seed dispersal, seedling establishment success, and growth, are likely to have a major role in determining the presence of this species in the successional vegetation patches scattered over the studied premontane area.

Autonomous selfing - Costa Rica - chiropterophily - Monteverde - pollination - self-compatibility.

References

• 1 Ackerman J. D.. Coping with the epiphytic existence: pollination strategies.  Selbyana. (1986);  9 52-60
• 2 Baker H. G.. Self-compatibility and establishment after “long-distance” dispersal.  Evolution. (1955);  9 347-349
• 3 Benzing D. H.. Bromeliaceae: Profile of an Adaptive Radiation. Cambridge; Cambridge University Press (2000)
• 4 Bush S. P., Beach J. H.. Breeding systems of epiphytes in a tropical montane wet forest.  Selbyana. (1995);  16 155-158
• 5 Faegri K., van der Pijl L.. The Principles of Pollination Ecology. Oxford; Pergamon (1979)
• 6 Fleming T. H., Sosa V. J.. Effects of nectarivorous and frugivorous mammals on reproductive success of plants.  Journal of Mammalogy. (1994);  75 845-851
• 7 Gardner C. S.. Inferences about pollination in Tillandsia (Bromeliaceae).  Selbyana. (1986);  9 76-87
• 8 Gates M. W., Cascante-Marín A.. A new phytophagous species of Eurytoma (Hymenoptera: Eurytomidae) attacking Werauhia gladioliflora (Bromeliales: Bromeliaceae).  Zootaxa. (2004);  512 1-10
• 9 Martinelli G.. Reproductive biology of Bromeliaceae in the Atlantic rain forest of Southeastern Brazil. PhD thesis, University of St. Andrews. (1994)
• 10 Morales J. F.. Bromeliaceae. Hammel, B. E., Grayum, M. H., Herrera, C., and Zamora, N., eds. Manual de Plantas de Costa Rica. Vol. II: Monocotiledóneas (Agavaceae-Musaceae). St. Louis; Missouri Botanical Garden Press (2003)
• 11 Nadkarni N. M., Wheelwright N. T.. eds. .Monteverde: Ecology and Conservation of a Tropical Cloud Forest. New York; Oxford University Press (2000)
• 12 Nieder J., Engwald S., Klawun M., Barthlott W.. Spatial distribution of vascular epiphytes (including Hemiepiphytes) in a lowland amazonian rain forest (Surumoni Crane Plot) of Southern Venezuela.  Biotropica. (2000);  32 385-396
• 13 Oostermeijer J. G. B., van Eijck M. W., den Nijs H. C. M.. Offspring fitness in relation to population size and genetic variation in the rare perennial plant species Gentiana pneumonanthe (Gentianaceae).  Oecologia. (1994);  97 289-296
• 14 Opler P. A., Baker H. G., Frankie G. W.. Plant reproductive characteristics during secondary succession in neotropical lowland forest ecosystems.  Biotropica. (1980);  12 (Suppl.) 40-46
• 15 Sazima M., Buzato S., Sazima I.. Bat pollination of Vriesea in southeastern Brazil.  Bromélia. (1995);  2 29-37
• 16 StatSoft, Inc. .STATISTICA for Windows: computer program manual. Tulsa; StatSoft, Inc (2000)
• 17 Tremblay R. L.. Distribution and dispersion patterns of individuals in nine species of Lepanthes (Orchidaceae).  Biotropica. (1997);  29 38-45
• 18 Tschapka M., Dressler S.. Chiropterophily: on bat-flowers and flower bats.  Curtis's Botanical Magazine. (2002);  19 114-125
• 19 van Dunné H. J. F.. Effects of the spatial distribution of trees, conspecific epiphytes and geomorphology on the distribution of epiphytic bromeliads in a secondary montane forest (Cordillera Central, Colombia).  Journal of Tropical Ecology. (2002);  18 198-213
• 20 Vogel S.. Chiropterophilie in der neotropischen Flora. Neue Mitteil. III.  Flora. (1969);  158 289-323
• 21 Zar J. H.. Biostatistical Analysis. New Jersey; Prentice-Hall, Inc (1999)

Editor: F. R. Scarano