Featured Research

from universities, journals, and other organizations

Friends, Enemies Communicate With Plants In Similar Ways

Date:
February 28, 2005
Source:
North Carolina State University
Summary:
Two soil-dwelling strangers – a friend and a foe – approach a plant and communicate with it in order to enter a partnership. The friend wants to trade nitrogen for food. The foe is a parasite that wants to burrow in and harm the plant.

Fluorescence confocal microscope images of plant epidermal and root hair cells expressing Green Fluorescent Protein (GFP) fused with microtubule associated protein, MAP4 (left), and actin binding protein, Talin (right). New evidence confirms that root-knot nematodes and rhizobia produce an essentially identical cytoskeletal response in these tiny root hairs of L. japonicus.
Credit: Image courtesy of North Carolina State University

Two soil-dwelling strangers – a friend and a foe – approach a plant and communicate with it in order to enter a partnership. The friend wants to trade nitrogen for food. The foe is a parasite that wants to burrow in and harm the plant.

In a new finding published in Proceedings of the National Academy of Sciences, researchers at North Carolina State University have found that the two strangers communicate with the plant in very similar ways. The plant’s responses to both friend and foe are also remarkably similar.

Using high-tech microscopy and florescent imaging techniques that allow for real-time, three-dimensional study in living cells over time, the NC State researchers discovered that the model legume Lotus japonicus responded similarly to signals from both rhizobia, the friends that fix nitrogen for the plant, and root-knot nematodes, the parasitic foes that want to harm the plant. Signals from both outsiders induce rapid changes in distribution of the plant’s cytoskeleton, which is part of a pathway that leads to a series of growth changes that include the formation of either nodules housing bacteria or giant cells from which the nematodes feed.

The scientists also discovered that, like rhizobia and contrary to popular belief, the root-knot nematode signals plants from a distance and therefore does not need to attach itself to the plant to elicit a response.

When the researchers studied L. japonicus plants missing the receptors that receive signals from other organisms – certain genes in the plant were modified to accomplish this – they discovered that the plants failed to respond to signals from both friend and foe, and therefore no changes were viewed in the plant’s cytoskeleton.

“This exquisite system that plants have developed to allow beneficial interactions with other organisms like rhizobia is being exploited by nematodes,” says Dr. David Bird, associate professor of plant pathology, co-director of NC State’s Center for the Biology of Nematode Parasitism and co-author of the paper. “Nematodes have not only found a weak link in plants but may be using the very same bacterial machinery against it.”

The study started as a graduate research project of Ravisha R. Weerasinghe, the lead author of the paper, in the lab of Dr. Nina Allen, professor of botany and co-author of the paper. Weerasinghe first observed the changes in the plants triggered by signals from rhizobia, called Nod factors, and then saw the similar changes occurring when plants were signaled by root-knot nematodes. In the paper, the researchers call the nematodes’ signals “Nematode factors.”

After rhizobia perceive plant signals and send back Nod factors, the plant’s root hairs curl around the good bacteria. The rhizobia then migrate into the root and form special structures called nodules, where they turn atmospheric nitrogen into usable nitrogen for the plant and, in return, take some of the plant’s energy to survive. A similar relationship appeared when Weerasinghe studied the signals between plants and nematodes, even though the nematode provides no benefit to its host. Root-knot nematodes form feeding cells – so-called giant cells – in the plant and later galls or knots on it.

“We don’t know the precise structure of Nematode factor, but it appears that the nematodes may have actually acquired genes from rhizobia to exploit this signal pathway,” Bird says.

The research was funded by the National Science Foundation and the North Carolina Research Station.


Story Source:

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


Cite This Page:

North Carolina State University. "Friends, Enemies Communicate With Plants In Similar Ways." ScienceDaily. ScienceDaily, 28 February 2005. <www.sciencedaily.com/releases/2005/02/050224114043.htm>.
North Carolina State University. (2005, February 28). Friends, Enemies Communicate With Plants In Similar Ways. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2005/02/050224114043.htm
North Carolina State University. "Friends, Enemies Communicate With Plants In Similar Ways." ScienceDaily. www.sciencedaily.com/releases/2005/02/050224114043.htm (accessed July 22, 2014).

Share This




More Plants & Animals News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Michigan Plant's Goal: Flower and Die

Michigan Plant's Goal: Flower and Die

AP (July 22, 2014) An 80-year-old agave plant, which is blooming for the first and only time at a University of Michigan conservatory, will die when it's done (July 22) Video provided by AP
Powered by NewsLook.com
San Diego Zoo Welcomes New, Rare Rhino Calf

San Diego Zoo Welcomes New, Rare Rhino Calf

Reuters - US Online Video (July 21, 2014) An endangered black rhino baby is the newest resident at the San Diego Zoo. Sasha Salama reports. Video provided by Reuters
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
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