J Plant Ecol ›› 2010, Vol. 3 ›› Issue (4): 243-250 .DOI: 10.1093/jpe/rtq012

• Research Articles • Previous Articles     Next Articles

Generalized food-deceptive orchid species flower earlier and occur at lower altitudes than rewarding ones

Loïc Pellissier1,*, Pascal Vittoz1,2, Antonina Ingrid Internicola1,4 and Luc Daniel Bienvenu Gigord3   

  1. 1 Department of Ecology and Evolution, University of Lausanne, Biophore, CH-1015 Lausanne, Switzerland; 2 Faculty of Geosciences and Environment, University of Lausanne, Biophore, CH-1015 Lausanne, Switzerland; 3 Conservatoire Botanique National de Mascarin, 2 rue du Père Georges, Les Colimaçons, 97436 Saint-Leu, La Réunion, France; 4 Present address: Department of Biological Sciences, 2500 University Drive N.W., University of Calgary, Calgary AB, Alberta, Canada T2N 1N4
  • Received:2009-07-31 Accepted:2010-04-16 Published:2010-11-04
  • Contact: Gigord, Luc

Generalized food-deceptive orchid species flower earlier and occur at lower altitudes than rewarding ones

Abstract: Aims Food-deceptive pollination, in which plants do not offer any food reward to their pollinators, is common within the Orchidaceae. As food-deceptive orchids are poorer competitors for pollinator visitation than rewarding orchids, their occurrence in a given habitat may be more constrained than that of rewarding orchids. In particular, the success of deceptive orchids strongly relies on several biotic factors such as interactions with co-flowering rewarding species and pollinators, which may vary with altitude and over time. Our study compares generalized food-deceptive (i.e. excluding sexually deceptive) and rewarding orchids to test whether (i) deceptive orchids flower earlier compared to their rewarding counterparts and whether (ii) the relative occurrence of deceptive orchids decreases with increasing altitude.
Methods To compare the flowering phenology of rewarding and deceptive orchids, we analysed data compiled from the literature at the species level over the occidental Palaearctic area. Since flowering phenology can be constrained by the latitudinal distribution of the species and by their phylogenetic relationships, we accounted for these factors in our analysis. To compare the altitudinal distribution of rewarding and deceptive orchids, we used field observations made over the entire Swiss territory and over two Swiss mountain ranges.
Important findings We found that deceptive orchid species start flowering earlier than rewarding orchids do, which is in accordance with the hypotheses of exploitation of naive pollinators and/or avoidance of competition with rewarding co-occurring species. Also, the relative frequency of deceptive orchids decreases with altitude, suggesting that deception may be less profitable at high compared to low altitude.

Key words: altitude, timing of flowering, food-deception, European orchids, Orchidaceae, biogeography

摘要:
Aims Food-deceptive pollination, in which plants do not offer any food reward to their pollinators, is common within the Orchidaceae. As food-deceptive orchids are poorer competitors for pollinator visitation than rewarding orchids, their occurrence in a given habitat may be more constrained than that of rewarding orchids. In particular, the success of deceptive orchids strongly relies on several biotic factors such as interactions with co-flowering rewarding species and pollinators, which may vary with altitude and over time. Our study compares generalized food-deceptive (i.e. excluding sexually deceptive) and rewarding orchids to test whether (i) deceptive orchids flower earlier compared to their rewarding counterparts and whether (ii) the relative occurrence of deceptive orchids decreases with increasing altitude.
Methods To compare the flowering phenology of rewarding and deceptive orchids, we analysed data compiled from the literature at the species level over the occidental Palaearctic area. Since flowering phenology can be constrained by the latitudinal distribution of the species and by their phylogenetic relationships, we accounted for these factors in our analysis. To compare the altitudinal distribution of rewarding and deceptive orchids, we used field observations made over the entire Swiss territory and over two Swiss mountain ranges.
Important findings We found that deceptive orchid species start flowering earlier than rewarding orchids do, which is in accordance with the hypotheses of exploitation of naive pollinators and/or avoidance of competition with rewarding co-occurring species. Also, the relative frequency of deceptive orchids decreases with altitude, suggesting that deception may be less profitable at high compared to low altitude.