Featured Research

from universities, journals, and other organizations

Plants Vs. Disease: "Trench Warfare At The Molecular Level"

Date:
July 23, 2001
Source:
Cornell University
Summary:
By observing the battle between bacterial speck disease and tomatoes, biologists have discovered how plant cells resist some ailments. Researchers from the Boyce Thompson Institute (BTI) for Plant Research Inc. and Cornell University can now demonstrate how disease-causing organisms deliver destructive agents to plants, and how the plants fight back.

PROVIDENCE, R.I. -- By observing the battle between bacterial speck disease and tomatoes, biologists have discovered how plant cells resist some ailments. Researchers from the Boyce Thompson Institute (BTI) for Plant Research Inc. and Cornell University can now demonstrate how disease-causing organisms deliver destructive agents to plants, and how the plants fight back.

"It's like radar detecting an incoming missile" says Gregory B. Martin, senior scientist at BTI and a Cornell plant pathologist. "Consider it trench warfare at the molecular level." While Cornell and BTI are both located in Ithaca, N.Y., Martin will present this information to a plenary session of the American Society of Plant Biologists on Tuesday, July 24, at 4 p.m. at the Rhode Island Convention Center in Providence. The session is titled "Signal transduction mechanisms in plant defense activation."

One combatant is Pseudomonas syringae , the bacterium responsible for causing bacterial speck disease. Martin and his colleagues have learned that P. syringae attacks healthy tomato plants by attaching itself to the plant cell, inserting a microscopic tube and sending a pathogenic protein -- like ammunition -- into the cell.

Despite the attack, the plant cell is prepared for the invading onslaught. Using a molecular surveillance system behind the cell wall, the plant cell detects alien proteins and mounts a defense.

Although bacterial speck disease has been known since the early 1930s, it did not result in serious losses until the winter tomato crop of 1977-78 in southern Florida. Cool, moist

environmental conditions contributed to the development of the disease, and it has now established itself as a major production problem, according to Thomas A. Zitter, Cornell professor of plant pathology.

The disease produces black lesions, often with a discrete yellow halo that can appear on the plant leaves and cause them to curl. Growers had been instructed to spray a copper-based pesticide to ward off bacterial speck. But, over the years, the disease became resistant to the copper, rendering the pesticide virtually useless. The disease is now controlled by naturally-occurring resistance genes that are bred into certain tomato plants.

A project centered at Cornell is determining the DNA sequence of all the genes of P. syringae . Martin and colleagues are then concentrating on those genes which produce proteins involved in causing plant disease.

Describing the importance of the Pseudomonas gene sequences to the botanical and agricultural world, Martin said it was "analogous to sequencing the human genome or the Arabidopsis genome." He explained that while the human genome has about 25,000 genes, P. syringae has about 6,000. As with the human genome sequence, knowing the entire set of genes encoded by an organism give scientists the entire blueprint for how that organism behaves. Cornell and BTI scientists were able to find nearly 30 genes in the P. syringae bacterium involved in the attack and resistance system. "Research over the past 10 years has explained the array of surveillance proteins produced by plants and we now know the entire set of attacking proteins of this bacterium," says Martin.

This research was made possible thanks to a five-year, $5 million grant from the National Science Foundation, which was awarded last fall. Alan Collmer, Cornell professor of plant pathology, serves as the primary investigator on this grant.

Joining Martin on this research: Cornell graduate students Nai-Chun Lin, Anjali Iyer, Jeffrey Anderson, Hye-Sook Oh, Rob Abramovitch, and Pete Pascuzzi; post-doctoral scientists Young Jin Kim and Jonathan Cohn; and Purdue University graduate student Brendan Riely.

Tomatoes belong to the Solanaceae family, a large group of plants that include potatoes, peppers, eggplants, tobacco and petunias. Economically, the Solanaceae family is one of the most valuable crop families in the United States, says Collmer. In 1999, about 494,000 acres of tomatoes for the fresh market and commercial processing were planted, and about 482,090 acres were harvested in the United States, according to the USDA's Economic Research Service. This accounts for 29.2 billion pounds of tomatoes grown that year, or about 60,600 pounds per acre. For the crop in 1999, this represented a farm value of about $1.8 billion.


Story Source:

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


Cite This Page:

Cornell University. "Plants Vs. Disease: "Trench Warfare At The Molecular Level"." ScienceDaily. ScienceDaily, 23 July 2001. <www.sciencedaily.com/releases/2001/07/010723102016.htm>.
Cornell University. (2001, July 23). Plants Vs. Disease: "Trench Warfare At The Molecular Level". ScienceDaily. Retrieved September 15, 2014 from www.sciencedaily.com/releases/2001/07/010723102016.htm
Cornell University. "Plants Vs. Disease: "Trench Warfare At The Molecular Level"." ScienceDaily. www.sciencedaily.com/releases/2001/07/010723102016.htm (accessed September 15, 2014).

Share This



More Plants & Animals News

Monday, September 15, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Conservationists Face Uphill PR Battle With New Shark Rules

Conservationists Face Uphill PR Battle With New Shark Rules

Newsy (Sep. 14, 2014) New conservation measures for shark fishing face an uphill PR battle in the fight to slow shark extinction. Video provided by Newsy
Powered by NewsLook.com
Shocker: Journalists Are Utterly Addicted To Coffee

Shocker: Journalists Are Utterly Addicted To Coffee

Newsy (Sep. 13, 2014) A U.K. survey found that journalists consumed the most amount of coffee, but that's only the tip of the coffee-related statistics iceberg. Video provided by Newsy
Powered by NewsLook.com
Lion Cubs the Pride of San Diego Zoo

Lion Cubs the Pride of San Diego Zoo

Reuters - US Online Video (Sep. 13, 2014) Roars of excitement as a proud lioness shows off her four cubs at the San Diego Zoo Safari Park. Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
'Magic Mushrooms' Could Help Smokers Quit

'Magic Mushrooms' Could Help Smokers Quit

Newsy (Sep. 11, 2014) In a small study, researchers found that the majority of long-time smokers quit after taking psilocybin pills and undergoing therapy sessions. 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