Featured Research

from universities, journals, and other organizations

Plant Cells 'Black Out' When Eaten By Leafworms

Date:
March 20, 2006
Source:
Max Planck Society
Summary:
When an Egyptian cotton leafworm eats the leaves of a lima bean plant, the natural voltage at the membranes of the plant's cells changes in a matter of seconds. This insight is the result of investigations by scientists led by Professor Massimo Maffei of the University of Turin, Italy, and Professor Wilhelm Boland, of the Max Planck Institute for Chemical Ecology in Jena. The membrane potential drops abruptly; within a short space of time, depolarisation spreads out across the leaf under attack.

Magnified view of a leaf where leafworms have been feeding. The green colouring indicates calcium-ion influx.
Credit: Image : Simone Bossi, University of Turin

When an Egyptian cotton leafworm eats the leaves of a lima bean plant, the natural voltage at the membranes of the plant’s cells changes in a matter of seconds. This insight is the result of investigations by scientists led by Professor Massimo Maffei of the University of Turin, Italy, and Professor Wilhelm Boland, of the Max Planck Institute for Chemical Ecology in Jena. The membrane potential drops abruptly; within a short space of time, depolarisation spreads out across the leaf under attack. This "electrical black out" drastically reduces the ability of the plant’s cells to react and protect themselves against getting eaten by the leafworm. The scientists are now trying to determine the identity, origins, and functioning of every substance responsible for these electrical changes (Plant Physiology, March 13, 2006).

Every cell is surrounded by a plasma membrane. It determines the cell’s dimensions and controls differences between the cell’s contents and its environment. The membrane thus determines how nutrients enter the cell. This creates varying ion concentrations between its interior and exterior and generates membrane potential. Experiments in the current study have shown that in the case of lima bean leaves (Phaseolus lunatus) attacked by Egyptian cotton leafworms (Spodoptera littoralis), the voltage at the membrane drops from about -130 to -90 millivolts within seconds. This depolarisation spreads out quickly across the attacked leaf.

The scientists then moved on to investigate if this electrical effect plays any role in protecting lima bean plants against their attackers. The researchers investigated two defence and signalling substances in leaves attacked by pathogens: Hydrogen peroxide (H2O2), and calcium ions. The scientists used soybean cell cultures to determine that cellular calcium ion amounts increased with concentration of hydrogen peroxide in the nutrient solution. A confocal Laser Scanning Microscope (see image) then showed that calcium ion concentration in the attacked leaves - in the presence ofH2O2 - was clearly smaller than in mechanically wounded leaves. That could itself drastically reduce the ability of the plant’s cells to react.

Voltages across biological membranes are important and measurable features of every living cell - human, animal, or plant. Thus, plasma membranes also serve to detect and communicate external signals, allowing cells and entire tissues to react efficiently to changes in their environment. Pests eating plants are one example. Whether the depolarisation measured in this experiment ultimately benefits the pest, as it appears, and not the plant, still needs to be investigated.


Story Source:

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


Cite This Page:

Max Planck Society. "Plant Cells 'Black Out' When Eaten By Leafworms." ScienceDaily. ScienceDaily, 20 March 2006. <www.sciencedaily.com/releases/2006/03/060319183656.htm>.
Max Planck Society. (2006, March 20). Plant Cells 'Black Out' When Eaten By Leafworms. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2006/03/060319183656.htm
Max Planck Society. "Plant Cells 'Black Out' When Eaten By Leafworms." ScienceDaily. www.sciencedaily.com/releases/2006/03/060319183656.htm (accessed July 22, 2014).

Share This




More Health & Medicine News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
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
Tooth Plaque Provides Insight Into Diets Of Ancient People

Tooth Plaque Provides Insight Into Diets Of Ancient People

Newsy (July 19, 2014) Research on plaque from ancient teeth shows that our prehistoric ancestor's had a detailed understanding of plants long before developing agriculture. Video provided by Newsy
Powered by NewsLook.com
Contaminated Water Kills 3 Babies in South African Town

Contaminated Water Kills 3 Babies in South African Town

AFP (July 18, 2014) Contaminated water in South Africa's northwestern town of Bloemhof kills three babies and hospitalises over 500 people. The incident highlights growing fears over water safety in South Africa. Duration: 02:22 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