Featured Research

from universities, journals, and other organizations

New technique improves sensitivity of PCR pathogen detection

Date:
April 22, 2011
Source:
USDA/Agricultural Research Service
Summary:
A new procedure can improve polymerase chain reaction (PCR)-based methods of detecting plant disease organisms.

A more sensitive test called “Bio-PCR” should prove useful for early detection of many bacteria, including the one that causes Pierce’s disease on grapes. Shown is an ARS-developed seedless variety, Autumn Royal.
Credit: Bob Nichols

A new procedure devised by U.S. Department of Agriculture (USDA) scientists and colleagues can improve polymerase chain reaction (PCR)-based methods of detecting plant disease organisms.

Related Articles


PCR-based tests are prized tools for diagnosing plant diseases that can cause yield losses and diminished markets among other economic harm. But the test's ability to obtain a "genetic fingerprint" conclusively identifying a culprit pathogen hinges on there being a minimum number of its cells. Otherwise, the pathogen's genetic material can't be probed and multiplied in amounts necessary for detection, explains plant pathologist Norm Schaad, formerly with USDA's Agricultural Research Service (ARS). ARS is USDA's principal intramural scientific research agency.

Such diagnostic shortcomings can be especially costly when asymptomatic seed or plants intended for sale are certified as pathogen-free when, in fact, they are not, adds Schaad. He worked at the ARS Foreign Disease-Weed Science Research Unit in Frederick, Md., prior to retiring last year.

To tackle the problem, Schaad and colleagues Nikolas Panopoulos and Efstathios Hatziloukas devised a preliminary step called Bio-PCR. It uses growth-promoting agar or liquid media to increase the number of a target organism's cells in a sample prior to amplification of genetic material. In four to 72 hours, depending on the pathogen, the cells make thousands of new copies, enabling detection by direct PCR, according to Schaad.

Besides increasing sensitivity by 100- to 1,000-fold over conventional PCR methods, the enrichment technique stops substances called inhibitors from interfering with the action of a key enzyme, Taq polymerase.

Bio-PCR works best with fast-growing bacteria such as Ralstonia solanacearum, which causes bacterial wilt of potato and tomato, and Acidovorax avenae, which causes bacterial fruit blotch of watermelon. However, Bio-PCR also improves detection of slow-growing pathogens such as Xylella fastidiosa, responsible for Pierce's disease of grapes and leaf scorch of shade trees.

In studies with X. fastidiosa, Bio-PCR detected the bacterium in 90 percent of infected grape samples compared to 13 percent with conventional PCR methods.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. The original article was written by Jan Suszkiw. Note: Materials may be edited for content and length.


Cite This Page:

USDA/Agricultural Research Service. "New technique improves sensitivity of PCR pathogen detection." ScienceDaily. ScienceDaily, 22 April 2011. <www.sciencedaily.com/releases/2011/04/110421104508.htm>.
USDA/Agricultural Research Service. (2011, April 22). New technique improves sensitivity of PCR pathogen detection. ScienceDaily. Retrieved January 30, 2015 from www.sciencedaily.com/releases/2011/04/110421104508.htm
USDA/Agricultural Research Service. "New technique improves sensitivity of PCR pathogen detection." ScienceDaily. www.sciencedaily.com/releases/2011/04/110421104508.htm (accessed January 30, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, January 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Brawling Pandas Are Violently Adorable

Brawling Pandas Are Violently Adorable

Buzz60 (Jan. 29, 2015) Video of pandas play fighting at the Chengdu Research Base in China will make your day. Mara Montalbano (@maramontalbano) shows us. Video provided by Buzz60
Powered by NewsLook.com
Why Researchers Say We Should Cut Back On Biofuels

Why Researchers Say We Should Cut Back On Biofuels

Newsy (Jan. 29, 2015) Biofuels aren&apos;t the best alternative to fossil fuels, according to a new report. In fact, they&apos;re quite a bad one. Video provided by Newsy
Powered by NewsLook.com
3-D Printed Wheelchair Helps Two-Legged Dog Learn to Run

3-D Printed Wheelchair Helps Two-Legged Dog Learn to Run

Buzz60 (Jan. 29, 2015) 3-D printing helps another two-legged dog run around with his four-legged friends. Jen Markham (@jenmarkham) has the adorable video. Video provided by Buzz60
Powered by NewsLook.com
Dogs Bring on So Many Different Emotions in Their Human Best Friends

Dogs Bring on So Many Different Emotions in Their Human Best Friends

RightThisMinute (Jan. 28, 2015) From new-puppy happy tears to helpful-grocery-carrying-dog laughter, our four-legged best friends can make us feel the entire spectrum of emotions. Video provided by RightThisMinute
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