Featured Research

from universities, journals, and other organizations

How some plants spread their seeds: Ready, set, catapult

Date:
November 4, 2010
Source:
American Journal of Botany
Summary:
Catapults are often associated with a medieval means of destruction, but for some plants, they are an effective way to launch new life. Dispersing seeds greater distances by catapulting can provide selective advantages, including the establishment of populations in new environments and escape from certain threats. Researchers measured the mechanics involved in catapulting seeds for the ballistic disperser Cardamine parviflora.

A cluster of ripening siliquae is pictured.
Credit: Dr. David J. Ellerby, Wellesley College, Wellesley, Massachusetts.

Catapults are often associated with a medieval means of destruction, but for some plants, they are an effective way to launch new life. Dispersing seeds greater distances by catapulting can provide selective advantages, including the establishment of populations in new environments and escape from certain threats.

Related Articles


In new work published in the recent October issue of American Journal of Botany, Dr. Ellerby, students, and postdoctoral researcher Shannon Gerry at Wellesley College measured the mechanics involved in catapulting seeds for the ballistic disperser Cardamine parviflora.

"While plants are generally thought of as immobile organisms, many of them are capable of spectacularly rapid movements," stated Ellerby. For C. parviflora, the valves of the silique rapidly coil outward catapulting the seeds away from the parent plant. The entire coiling and launching process is completed in around 5 msec -- faster than the blink of an eye.

Analysis of the launch showed that the catapulting mechanism is not very reliable in C. parviflora, with the majority of the seeds simply falling to the ground. For the seeds that were launched, however, the transference of stored energy to kinetic energy was ~20% efficient. An impressive number when compared to the 0.5% efficiency observed for a ballistic diplochore (Impatiens capensis) in a previous study of Ellerby and colleagues.

This incredible speed and high energy storage present a challenge for the researchers. "These seed pod catapults are on a hair trigger," said Ellerby. "Successfully positioning them in front of our high-speed camera without them exploding prematurely requires an incredibly steady hand."

Seed launching has evolved in a number of groups. Comparing the mechanics of seed dispersal and the morphology of fruits and seeds between plants utilizing ballistic methods and closely related plants that do not, can provide a deeper understanding of the evolution of ballistic mechanisms and the properties required for energy storage and transference.

Seed dispersal has been studied extensively in the model plant Arabidopsis thaliana, a close relation to Cardamine. Like most other members of the Brassicacae, A. thaliana does not disperse its seeds via catapulting. Instead, the seeds are dropped to the ground as the silique dehisces and splits. Despite these differences in seed dispersal mechanisms, the siliques of C. parviflora and A. thaliana are morphologically similar. One difference is the persistence of second layer on the inner surface of the valve in C. parviflora that degenerates in A. thaliana during maturation. This additional layer likely plays a role in valve coiling.

"Ultimately it will be important to analyze the spring-structures at a tissue and cellular level to determine precisely how they store such impressive amounts of energy," Ellerby said. "This could inform the design of human-engineered structures for absorbing or storing elastic energy."


Story Source:

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


Journal Reference:

  1. M. Hayashi, S. P. Gerry, D. J. Ellerby. The seed dispersal catapult of Cardamine parviflora (Brassicaceae) is efficient but unreliable. American Journal of Botany, 2010; 97 (10): 1595 DOI: 10.3732/ajb.1000173

Cite This Page:

American Journal of Botany. "How some plants spread their seeds: Ready, set, catapult." ScienceDaily. ScienceDaily, 4 November 2010. <www.sciencedaily.com/releases/2010/11/101103095123.htm>.
American Journal of Botany. (2010, November 4). How some plants spread their seeds: Ready, set, catapult. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2010/11/101103095123.htm
American Journal of Botany. "How some plants spread their seeds: Ready, set, catapult." ScienceDaily. www.sciencedaily.com/releases/2010/11/101103095123.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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