Phenotypic selection on floral scent: trade-off between attraction and deterrence?
Flowers emit a large variety of floral signals that play a fundamental role in the communication of plants with their mutualists and antagonists. We investigated phenotypic selection on floral scent and floral display using the rewarding orchid species Gymnadenia odoratissima. We found positive directional selection on inflorescence size, as well as positive and negative selection on floral scent compounds. Structural equation modeling showed that “active” compounds, i.e. those that were shown in earlier investigations to be detected by pollinator insects, were positively linked to fitness, whereas “non-active” were negatively linked to fitness. Our results suggest that different patterns of selection impact on different scent compounds, which may relate to the functions of compounds for attracting/deterring insects.
KeywordsPollination Floral evolution VOC Plant volatiles Herbivory
We would like to thanks three anonymous reviewer as well as the handling editor, Arien Biere, for their valuable comments on an earlier version of this manuscript. We also thank Roman Kaiser for his help with identifying scent compounds.
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