Dataset Information

Adding perches for cross-pollination ensures the reproduction of a self-incompatible orchid.

ABSTRACT:

Background

Outcrossing is known to carry genetic advantages in comparison with inbreeding. In many cases, flowering plants develop a self-incompatibility mechanism, along with a floral component adaptation mechanism, to avoid self-pollination and to promote outbreeding. Orchids commonly have a lip in their flower that functions as the a visiting plate for insect pollinators. Aside from the lip, however, many species (including Coelogyne rigida) have sheaths around the axis of inflorescence. The function of these sheaths remains unknown, and has long been a puzzle to researchers.

Methodology/principal findings

We investigated the function of these sheaths in relation to the lip and the pollinators, as well as their role in the modes of pollination and reproduction of Coelogyne rigida in 30 flowering populations of orchids in the limestone area of Southeast Yunnan, China. We found that self-incompatible C. rigida developed specialized bird perches around the basal axis of inflorescence to attract sunbirds and to complement their behavioral tendency to change foraging locations frequently. This self-incompatibility mechanism operates separately from the floral component adaptation mechanism. This mechanism thus prevents bees from repeatedly visiting the floral lip of the same plant which, in turn, results in autogamy. In this way, instead of preventing autogamy, C. rigida responds to these negative effects through a highly efficient cross-pollination method that successfully transfers pollen to different plants.

Conclusions

The proposed method ensures reproductive success, while offsetting the infertile self-pollination by insects, thereby reducing mating costs and addressing the lack of cross-pollination. The adaptation provides a novel and striking example of structural adaptation that promotes cross-pollination in angiosperms.

SUBMITTER: Liu ZJ

PROVIDER: S-EPMC3538729 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Publications

Adding perches for cross-pollination ensures the reproduction of a self-incompatible orchid.

Liu Zhong-Jian ZJ Chen Li-Jun LJ Liu Ke-Wei KW Li Li-Qiang LQ Rao Wen-Hui WH Zhang Yu-Ting YT Tang Guang-Da GD Huang Lai-Qiang LQ

PloS one 20130107 1

<h4>Background</h4>Outcrossing is known to carry genetic advantages in comparison with inbreeding. In many cases, flowering plants develop a self-incompatibility mechanism, along with a floral component adaptation mechanism, to avoid self-pollination and to promote outbreeding. Orchids commonly have a lip in their flower that functions as the a visiting plate for insect pollinators. Aside from the lip, however, many species (including Coelogyne rigida) have sheaths around the axis of inflorescen ...[more]

PMID: 23308277

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Dataset Information

Adding perches for cross-pollination ensures the reproduction of a self-incompatible orchid.

Background

Methodology/principal findings

Conclusions

Publications

Adding perches for cross-pollination ensures the reproduction of a self-incompatible orchid.

Similar Datasets

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