Featured Research

from universities, journals, and other organizations

Orchid adding bird perch for crossing ensures reproduction

Date:
January 8, 2013
Source:
ResearchSEA
Summary:
Chinese researchers have solved the mystery of the function of sheaths in flowering orchids. In a new paper, the team found the perch to be essential to orchid reproduction.

Sheaths surrounding the basal axis (perch) of C. rigida inflorescences attract and position sunbirds for cross-pollination to ensure reproductive success. A. Inflorescence with the sheathed bird perch (arrow). B. A bird (male) on a perch bends down to probe flowers. C. Pollinaria (arrow) attached to different spots on the bird beak are cross-transferred to flowers with equivalent distances to perch. D. Fruit set from cross-pollination. E. A wasp and F. a honeybee visit flowers in the same manner, both causing infertile self-pollination.
Credit: Zhong-Jian Liu, Li-Jun Chen, Ke-Wei Liu, Li-Qiang Li, Wen-Hui Rao, Yu-Ting Zhang, Guang-Da Tang, Lai-Qiang Huang. Adding Perches for Cross-Pollination Ensures the Reproduction of a Self-Incompatible Orchid. PLoS ONE, 2013; 8 (1): e53695 DOI: 10.1371/journal.pone.0053695

Chinese researchers have solved the mystery of the function of sheaths in flowering orchids. In a paper published in PLOS ONE, the team led by Zhong-Jian Liu at the Orchid Conservation & Research Center of Shenzhen and Laiqiang Huang at Tsinghua University found the perch to be essential to orchid reproduction.

In many orchids such as Coelogyne rigida, the basal axis of the pendulous, multi-flowered inflorescence is covered by multiple coriaceous sheaths (bracts) forming a clavate cylindrical handle whose function has long been a puzzle and remained mysterious until today.

A team led by Zhong-Jian Liu at the Orchid Conservation & Research Center of Shenzhen and Laiqiang Huang at Tsinghua University investigated the function of the sheaths in flowering populations of C. rigida in the limestone area of Southeast Yunnan, China, and have solved the mystery. They discovered that the sheaths-wrapped handle serves as the specialized perch (landing platform) to attract, secure and position foraging sunbird, Aethopyga gouldiae, for orderly collection and dispersal of pollinaria, attached to different spots of its beak, resulting in efficient cross-pollination and fruiting. The perch-enabled cross-pollination by sunbirds accounts for essentially all the seed production of this orchid, which was largely abolished by sheaths removal (perch damage) that reduced the visitations by sunbirds markedly both in frequency and duration, revealing an essential role of the perch in assuring the species' reproductive success by crossing.

Intriguingly, C. rigida, while self-incompatible, has a bi-modal pollination system. It is also self-pollinated by insects, honeybee and wasp, that use the floral lip common in orchids as visiting plate, leading to infertile self-pollination which decreases (wastes) pollinaria and ovules otherwise available for fruitful cross-pollination, incurring high mating cost (gamete discounting). However, the insect-mediated fruitless self-pollination is offset by the efficient cross-pollination by sunbird.

This represents a new and striking mode of structural adaptation that promotes cross-pollination in angiosperms. By merely adding a perch to the basal axis of inflorescence without altering the multiple flowers on it, C. rigida gains not only reproductive assurance but also mating and fertility advantages and genetic variability from crossing. It is likely that in C. rigida, self-incompatibility has evolved to avoid inbreeding depression by rendering insect self-pollination infertile, but it can't prevent self-pollination that still leads to gamete discounting at a high cost to mating, nor directly promote crossing which becomes essential for sexual reproduction; which, in turn, necessitates and selects for the evolution of an outbreeding mechanism -- the perch-enabled bird cross-pollination to assure reproductive success with multiple advantages. The findings may have broad implications for many other plant species with inflorescences and sheaths.


Story Source:

The above story is based on materials provided by ResearchSEA. Note: Materials may be edited for content and length.


Journal Reference:

  1. Zhong-Jian Liu, Li-Jun Chen, Ke-Wei Liu, Li-Qiang Li, Wen-Hui Rao, Yu-Ting Zhang, Guang-Da Tang, Lai-Qiang Huang. Adding Perches for Cross-Pollination Ensures the Reproduction of a Self-Incompatible Orchid. PLoS ONE, 2013; 8 (1): e53695 DOI: 10.1371/journal.pone.0053695

Cite This Page:

ResearchSEA. "Orchid adding bird perch for crossing ensures reproduction." ScienceDaily. ScienceDaily, 8 January 2013. <www.sciencedaily.com/releases/2013/01/130108091347.htm>.
ResearchSEA. (2013, January 8). Orchid adding bird perch for crossing ensures reproduction. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2013/01/130108091347.htm
ResearchSEA. "Orchid adding bird perch for crossing ensures reproduction." ScienceDaily. www.sciencedaily.com/releases/2013/01/130108091347.htm (accessed April 16, 2014).

Share This



More Plants & Animals News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Outbreak Now Linked To 121 Deaths

Ebola Outbreak Now Linked To 121 Deaths

Newsy (Apr. 15, 2014) The ebola virus outbreak in West Africa is now linked to 121 deaths. Health officials fear the virus will continue to spread in urban areas. Video provided by Newsy
Powered by NewsLook.com
In Washington, a Push to Sterilize Stray Cats

In Washington, a Push to Sterilize Stray Cats

AFP (Apr. 14, 2014) To curb the growing numbers of feral cats in the US capital, the Washington Humane Society is encouraging residents to set traps and bring the animals to a sterilization clinic, after which they are released.. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
After Attack, Officials Kill 5 Bears in Florida

After Attack, Officials Kill 5 Bears in Florida

AP (Apr. 14, 2014) Florida wildlife officials say they have killed five bears following an attack on a woman in a suburban subdivision in central Florida. Forty-five year-old Terri Frana was attacked by a large bear in her driveway Saturday. (April 14) Video provided by AP
Powered by NewsLook.com
Uruguay Opens Its First Cannabis Library

Uruguay Opens Its First Cannabis Library

AFP (Apr. 13, 2014) Uruguay opened its first Cannabis Library in Montevideo on Saturday, where people can come and read books on cannabis or take classes on how to grow the plant or even how to cook with it. Duration: 01:20 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins