Featured Research

from universities, journals, and other organizations

A Virulent Strain Of The Fungus That Caused The Irish Potato Famine Is Devastating Crops In North America, Cornell Scientist Says

Date:
March 13, 1998
Source:
Cornell University
Summary:
The fungus responsible for the Irish Potato Famine of the 1840s is back, and could be more threatening than ever. More than 150 years after the famine that took an estimated 1 million lives, a newer virulent strain of the fungus is causing widespread crop devastation in the United States.

ITHACA, N.Y. -- The fungus responsible for the Irish Potato Famine of the1840s is back, and could be more threatening than ever. More than 150years after the famine that took an estimated 1 million lives, a newervirulent strain of the fungus is causing widespread crop devastation in theUnited States.

Agricultural scientists are finding the fungus, "Phytopthora infestans",better known as late blight, difficult to control, says William Fry, aCornell University professor of plant pathology. Fry believes the newstrain of the fungus is a greater threat to potato and tomato crops in theU.S. and Canada than were previous strains because it is resistant to themost effective fungicide, and because the strain is more aggressive.

"Things are worse now than they were a few years ago," says Fry. He andStephen B. Goodwin, a U.S. Department of Agriculture researcher at PurdueUniversity, warn of the effects of the aggressive new strain of the fungusin an article in the journal "Plant Disease".

Before 1992 the new late blight strain, US-8 was not present in the UnitedStates or in Canada. In 1992 and 1993, the new strain struck New YorkState and Maine. By 1995, it was to be found in all eastern states (exceptVirginia and South Carolina), the eastern Canadian provinces (exceptNewfoundland), along the entire Canadian border, and in California andKansas. Last year, US-8 was also found in Idaho, Texas, Colorado, Nebraskaand South Dakota.

Scientists say that US-8 is now the most widely distributed strain of lateblight in the U.S., and, Fry says, it is also the most problematic becauseit is resistant to metalaxyl, a generic, commonly used (on late blight)fungicide. This resistance makes suppressing the fungal epidemic moredifficult, he says.

US-8 is more aggressive than US-1, the strain responsible for the IrishPotato Famine, which is easily controlled by metalaxyl, according to Fry.The new strain is remarkably rapid and destructive, devastating apparentlyhealthy potato fields within days.

In the article, the researchers explained a two-pronged problem: Why it isdifficult to detect low levels of late blight in a field and how the fungusreproduces rapidly. The late blight disease cycle of penetration,colonization, sporulation and dispersal can occur in less than five days.The researchers note that each individual late blight lesion can produce asmany as 300,000 sporangia a day. Some infected tubers may be destroyedbefore harvest, but with a multiplicity of virulent spores, harvestedpotatoes can easily become diseased in storage. Bacteria that causesoft-rot diseases often invade potato tubers infected with late blight,literally resulting in a "meltdown" of stored potatoes. Under severeinfection, entire storages have to be discarded.

Scientists began noticing late blight's resistance to metalaxl as long agoas 1980, Fry says. The fungicide is the only way to salvage crops infectedwith late blight. Other available fungicides are only effective whenapplied before late blight strikes. Many agriculturists consider suchtreatment as ineffective against the disease.

In the article, the researchers note that the short-term response has beento use more fungicide. Other solutions, such as developing diseaseresistant varieties, they say, could be five to 15 years away fromintroduction.

The article, "Re-emergence," appears in "Plant Disease" (Vol. 81, Number12, pages 1349-1357, December 1997.) Fry and Goodwin also co-authored anarticle, "Resurgence of the Irish Potato Famine Fungus," in the journal"BioScience" (June 1997).


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. "A Virulent Strain Of The Fungus That Caused The Irish Potato Famine Is Devastating Crops In North America, Cornell Scientist Says." ScienceDaily. ScienceDaily, 13 March 1998. <www.sciencedaily.com/releases/1998/03/980313024141.htm>.
Cornell University. (1998, March 13). A Virulent Strain Of The Fungus That Caused The Irish Potato Famine Is Devastating Crops In North America, Cornell Scientist Says. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/1998/03/980313024141.htm
Cornell University. "A Virulent Strain Of The Fungus That Caused The Irish Potato Famine Is Devastating Crops In North America, Cornell Scientist Says." ScienceDaily. www.sciencedaily.com/releases/1998/03/980313024141.htm (accessed August 28, 2014).

Share This




More Plants & Animals News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Super Healthful Fruits and Vegetables: Which Are Best?

Super Healthful Fruits and Vegetables: Which Are Best?

Ivanhoe (Aug. 27, 2014) We all know that it is important to eat our fruits and vegetables but do you know which ones are the best for you? Video provided by Ivanhoe
Powered by NewsLook.com
Bad Memories Turn Good In Weird Mouse Brain Study

Bad Memories Turn Good In Weird Mouse Brain Study

Newsy (Aug. 27, 2014) MIT researchers were able to change whether bad memories in mice made them anxious by flicking an emotional switch in the brain. Video provided by Newsy
Powered by NewsLook.com
Do Couples Who Smoke Weed Together Stay Together?

Do Couples Who Smoke Weed Together Stay Together?

Newsy (Aug. 27, 2014) A study out of University at Buffalo claims couples who smoke marijuana are less likely to experience intimate partner violence. Video provided by Newsy
Powered by NewsLook.com
Panda Might Have Faked Pregnancy To Get Special Treatment

Panda Might Have Faked Pregnancy To Get Special Treatment

Newsy (Aug. 27, 2014) A panda in China showed pregnancy symptoms that disappeared after two months of observation. One theory: Her pseudopregnancy was a ploy for perks. 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