Autor(es):
Vandewoestijne, S. 
; Róis, A.S. ; Caperta, A. ; Baguette, M. ; Tyteca, D.
Data: 2009
Identificador Persistente: http://hdl.handle.net/10400.5/2852
Origem: Repositório da UTL
Assunto(s): Ophrys; pollinator limitation; reproductive success; sexually deceptive orchids
Descrição
Research Paper Reproductive success (RS) in orchids in general, and in non-rewarding species
specifically, is extremely low. RS is pollinator and pollination limited in
food deceptive orchids, but this has rarely been studied in sexually deceptive
orchid species. Here, we tested the effects of several individual (plant height,
inflorescence size, nearest neighbour distance and flower position) and
population (patch geometry, population density and size) parameters on RS
in three sexually deceptive Ophrys (Orchidaceae) species. Inter-specific differences
were observed in RS of flowers situated in the upper versus the
lower part of the inflorescence, likely due to species-specific pollinator
behaviour. For all three species examined, RS increased with increasing
plant height, inflorescence size and nearest neighbour distance. RS generally
increased with decreasing population density and increasing patch elongation.
Given these results, we postulate that pollinator availability, rather
than pollinator learning, is the most limiting factor in successful reproduction
for sexually deceptive orchids. Our results also suggest that olfactory
‘display’ (i.e. versus optical display), in terms of inflorescence size (and covarying
plant height), plays a key role in individual RS of sexually deceptive
orchids. In this regard, several hypotheses are suggested and discussed.
