Dataset Information

The evolution of floral deception in Epipactis veratrifolia (Orchidaceae): from indirect defense to pollination.

ABSTRACT:

Background

It is estimated that floral deception has evolved in at least 7500 species of angiosperms, of which two thirds are orchids. Epipactis veratrifolia (Orchidaceae) is a model system of aphid mimicry as aphidophagous hoverflies lay eggs on false brood sites on their flowers. To understand the evolutionary ecology of floral deception, we investigated the pollination biology of E. veratrifolia across 10 populations in the Eastern Himalayas. We reconstructed the phylogeny of Epipactis and mapped the known pollination systems of previously studied species onto the tree.

Results

Some inflorescences of E. veratrifolia were so infested with aphids while they were still in bud that the some larvae of hoverflies developed to the third instar while flower buds opened. This indicated that adult female hoverflies were partly rewarded for oviposition. Although flowers failed to secrete nectar, they mimicked both alarm pheromones and aphid coloring of to attract female hoverflies as their exclusive pollinators. Phylogenetic mapping indicate that pollination by aphidophagous hoverflies is likely an ancestral condition in the genus Epipactis. We suggest that the biological interaction of aphid (prey), orchid (primary producer) and hoverfly (predator) may represent an intermediate stage between mutualism and deception in the evolution of pollination-by-deceit in E. veratrifolia.

Conclusions

Our analyses indicate that this intermediate stage may be used as a model system to interpret the origin of oviposition (brood site) mimicry in Epipactis. We propose the hypothesis that some deceptive pollination systems evolved directly from earlier (partly) mutualistic systems that maintained the fidelity of the original pollinator(s) even though rewards (nectar/ brood site) were lost.

SUBMITTER: Jin XH

PROVIDER: S-EPMC4007573 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Publications

The evolution of floral deception in Epipactis veratrifolia (Orchidaceae): from indirect defense to pollination.

Jin Xiao-Hua XH Ren Zong-Xin ZX Xu Song-Zhi SZ Wang Hong H Li De-Zhu DZ Li Zheng-Yu ZY

BMC plant biology 20140312

<h4>Background</h4>It is estimated that floral deception has evolved in at least 7500 species of angiosperms, of which two thirds are orchids. Epipactis veratrifolia (Orchidaceae) is a model system of aphid mimicry as aphidophagous hoverflies lay eggs on false brood sites on their flowers. To understand the evolutionary ecology of floral deception, we investigated the pollination biology of E. veratrifolia across 10 populations in the Eastern Himalayas. We reconstructed the phylogeny of Epipacti ...[more]

PMID: 24621377

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Dataset Information

The evolution of floral deception in Epipactis veratrifolia (Orchidaceae): from indirect defense to pollination.

Background

Results

Conclusions

Publications

The evolution of floral deception in Epipactis veratrifolia (Orchidaceae): from indirect defense to pollination.

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