Featured Research

from universities, journals, and other organizations

E. coli thrives near plant roots, can contaminate young produce crops

Date:
November 4, 2010
Source:
Purdue University
Summary:
E. coli can live for weeks around the roots of produce plants and transfer to the edible portions, but the threat can be minimized if growers don't harvest too soon, a new study shows.

Both images show plants grown in an agar substrate with a bioluminescent E. coli, which emits light when active. The E. coli associated with the roots are glowing (right) when viewed in the dark.
Credit: Photo provided by Bruce Applegate

E. coli can live for weeks around the roots of produce plants and transfer to the edible portions, but the threat can be minimized if growers don't harvest too soon, a Purdue University study shows.

Related Articles


Purdue scientists added E. coli to soil through manure application and water treated with manure and showed that the bacteria can survive and are active in the rhizosphere, or the area around the plant roots, of lettuce and radishes. E. coli eventually gets onto the aboveground surfaces of the plants, where it can live for several weeks. Activity in the rhizosphere was observed using a bioluminescent E. coli created by Bruce Applegate that glows when active. Applegate, a co-author on the project, is an associate professor in the food science and biological sciences departments at Purdue.

"E. coli is actually quite active in the rhizosphere. They're eating something there -- probably plant exudates," said Ron Turco, a professor of agronomy and co-author of the study published in the November issue of the Journal of Food Protection.

Turco said the E. coli didn't survive on the plants' surfaces more than 40 days after seeds were planted. Harvesting produce at least 40 days after planting should reduce the possibility of contamination, but he warned that E. coli could still come from other sources.

"In actual field application, you pick up other things that are all around," Turco said. "You don't just get the plants that are 40 days old. An animal getting loose in a field could also contaminate plants."

Mussie Habteselassie, Turco's former postdoctoral researcher and now an assistant professor of soil microbiology at the University of Georgia's Griffin campus, said harvesting practices in manure-treated fields can be critical for produce crops.

"If you harvest young and old plants together or mix them after harvesting, there is risk of contamination of the older plants," Habteselassie said. "If plants are uprooted during harvest, there is also a possibility of contamination from E. coli living in the rhizosphere."

Producers should apply manure to fields well in advance of planting and harvesting. Turco said a wait of 90-120 days between manure application and harvesting, with a minimum of 40 days between planting and harvesting, should minimize the chance of E. coli contamination.

Turco said he would continue studying E. coli's ability to survive in different situations, including in water and processed produce. The U.S. Department of Agriculture funded the research.


Story Source:

The above story is based on materials provided by Purdue University. The original article was written by Brian Wallheimer. Note: Materials may be edited for content and length.


Journal Reference:

  1. Habteselassie, Mussie Y.; Bischoff, Marianne; Applegate, Bruce; Reuhs, Bradley; Turco, Ronald F. Understanding the Role of Agricultural Practices in the Potential Colonization and Contamination by Escherichia coli in the Rhizospheres of Fresh Produce. Journal of Food Protection, 2010; 73 (11) [link]

Cite This Page:

Purdue University. "E. coli thrives near plant roots, can contaminate young produce crops." ScienceDaily. ScienceDaily, 4 November 2010. <www.sciencedaily.com/releases/2010/11/101103135340.htm>.
Purdue University. (2010, November 4). E. coli thrives near plant roots, can contaminate young produce crops. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2010/11/101103135340.htm
Purdue University. "E. coli thrives near plant roots, can contaminate young produce crops." ScienceDaily. www.sciencedaily.com/releases/2010/11/101103135340.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. 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:

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