Featured Research

from universities, journals, and other organizations

'Balanced' ecosystems seen in organic agriculture better at controlling pests, research finds

Date:
July 1, 2010
Source:
Washington State University
Summary:
There really is a balance of nature, but as accepted as that thought is, it has rarely been studied. Now, researchers have found that more balanced animal and plant communities typical of organic farms work better at fighting pests and growing a better plant.

WSU entomologist David Crowder looked at insect pests and their natural enemies in potatoes and found organic crops had more balanced insect populations in which no one species of insect has a chance to dominate.
Credit: Shelly Hanks, Washington State University

There really is a balance of nature, but as accepted as that thought is, it has rarely been studied. Now Washington State University researchers writing in the journal Nature have found that more balanced animal and plant communities typical of organic farms work better at fighting pests and growing a better plant.

The researchers looked at insect pests and their natural enemies in potatoes and found organic crops had more balanced insect populations in which no one species of insect has a chance to dominate. And in test plots, the crops with the more balanced insect populations grew better.

"I think 'balance' is a good term," says David Crowder, a post-doctorate research associate in entomology at Washington State University. "When the species are balanced, at least in our experiments, they're able to fulfill their roles in a more harmonious fashion."

Crowder and colleagues here and at the University of Georgia use the term "evenness" to describe the relatively equal abundance of different species in an ecosystem. Conservation efforts more typically concentrate on species richness -- the number of individual species -- or the loss of individual species. Crowder's paper is one of only a few to address the issue. It is the first the first to look at animal and fungal communities and at multiple points in the food chain.

The researchers say their results strengthen the argument that both richness and evenness need to be considered in restoring an ecosystem. The paper also highlights insect predator and prey relationships at a time when the potato industry and large French fry customers like McDonald's and Wendy's are being pushed to consider the ecological sustainability of different pest-control practices.

Conventional pest-management on farms often leads to biological communities dominated by a few species. Looking at conventional and organic potato farms in central Washington State's Columbia Basin, Crowder found that the evenness of natural pests differed drastically between the two types of farms. In the conventional fields, one species might account for four out of five insects. In the organic fields, the most abundant species accounted for as little as 38 percent of a field's insect predators and enemies.

Using field enclosures on Washington State University's Pullman campus, Crowder recreated those conditions using potato plants, Colorado potato beetles, four insect species and three soil pathogens that attack the beetles. When the predators and pathogens had similar numbers, says Crowder, "we would get significantly less potato beetles at the end of the experiment."

"In turn," he adds, "we'd get bigger plants."

Crowder says he is unsure why species evenness was lower in conventional crops. It could be from different types of fertilization or from insecticides killing some natural enemies more than others.


Story Source:

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


Journal Reference:

  1. David W. Crowder, Tobin D. Northfield, Michael R. Strand, William E. Snyder. Organic agriculture promotes evenness and natural pest control. Nature, 2010; 466 (7302): 109 DOI: 10.1038/nature09183

Cite This Page:

Washington State University. "'Balanced' ecosystems seen in organic agriculture better at controlling pests, research finds." ScienceDaily. ScienceDaily, 1 July 2010. <www.sciencedaily.com/releases/2010/06/100630132752.htm>.
Washington State University. (2010, July 1). 'Balanced' ecosystems seen in organic agriculture better at controlling pests, research finds. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2010/06/100630132752.htm
Washington State University. "'Balanced' ecosystems seen in organic agriculture better at controlling pests, research finds." ScienceDaily. www.sciencedaily.com/releases/2010/06/100630132752.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
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