Featured Research

from universities, journals, and other organizations

Ozone's impact on soybean yield: Reducing future losses

Date:
October 30, 2012
Source:
University of Illinois College of Agricultural, Consumer and Environmental Sciences
Summary:
Ozone is a pollutant that damages crops, particularly soybean. Researchers have investigated the responses of seven different soybean genotypes to eight ozone concentrations. The plants were exposed to ozone concentrations ranging from ambient levels of 38 parts per billion up to 200 parts per billion. They found that any increase above the ambient concentration was enough to reduce seed yield: roughly half a bushel per acre for each additional part per billion.

People tend to think of ozone as something in the upper atmosphere that protects Earth's surface from UV radiation. At the ground level, however, ozone is a pollutant that damages crops, particularly soybean.

Lisa Ainsworth, a University of Illinois associate professor of crop sciences and USDA Agricultural Research Service plant molecular biologist, said that establishing the exposure threshold for damage is critical to understanding the current and future impact of this pollutant.

"Most of my research is on measuring the effects of ozone on soybean, determining the mechanisms of response, and then trying to improve soybean tolerance to ozone so that we can improve soybean yields," she explained.

Ozone is highly reactive with membranes and proteins and is known to damage the human lung. It also harms plants, slowing photosynthesis and accelerating senescence. As a result, they take in and fix less carbon, reducing yield. Ainsworth said that ground level concentrations of ozone are already high enough to damage crop production.

"Ozone reacts very quickly once it enters the leaf through the stomata," she explained. "It can form other oxygen radicals and also hydrogen peroxide. Then a series of cascading reactions causes a decrease in photosynthesis, reducing stomata conductance."

The plant's response to ozone mimics a hypersensitive response to a pathogen attack. "At quite high concentrations of ozone, you can get leaf bronzing, stippling of the leaves, and necrotic spots," Ainsworth said. "At really high concentrations, you get cell death." The metabolic changes then feed forward to affect plant productivity.

Ainsworth's group conducted a two year study in 2009 and 2010 at the Soybean Free Air Concentration Enrichment (SoyFACE) facility at the U of I South Farms. It was the first dose-response experiment to look at ozone and soybean under completely open-air conditions.

They investigated the responses of seven different soybean genotypes to eight ozone concentrations. The plants were exposed to ozone concentrations ranging from ambient levels of 38 parts per billion up to 200 parts per billion. "This is quite high, but unfortunately, those kinds of concentrations are what very polluted areas of China and India are looking at today," Ainsworth said.

The researchers found that any increase above the ambient concentration was enough to reduce seed yield: roughly half a bushel per acre for each additional part per billion.

"This is significant," Ainsworth said. "Especially considering that background concentrations of ozone today vary year to year, anywhere from about 38 to 39 parts per billion to about 62. That can be 15 bushels per acre from one year to the next that farmers are losing to ozone." The researchers compared the results of this study, which used modern genotypes, with results from experiments conducted in controlled environments in the 1980s. They found that the responses of the modern genotypes were similar to those of the older genotypes.

"Breeders haven't inadvertently bred for ozone tolerance in more modern lines," Ainsworth said. "They're still sensitive to ozone, which means that farmers are still subject to these yearly variations in ozone and are losing yield accordingly."

Potential increases in background ozone are predicted to increase soybean yield losses by 9 to 19 percent by 2030. Levels were particularly high during this year's growing season because most days were sunny and warm, and thus they were favorable for ozone formation. Peaks on many days exceeded 80 parts per billion, twice the known sensitivity threshold.


Story Source:

The above story is based on materials provided by University of Illinois College of Agricultural, Consumer and Environmental Sciences. Note: Materials may be edited for content and length.


Journal Reference:

  1. Amy M. Betzelberger et al. Ozone Exposure-Response for U.S. Soybean Cultivars: Linear Reductions in Photosynthetic Potential, Biomass and Yield. Plant Physiology, October 2012 DOI: %u200B10.%u200B1104/%u200Bpp.%u200B112.%u200B205591

Cite This Page:

University of Illinois College of Agricultural, Consumer and Environmental Sciences. "Ozone's impact on soybean yield: Reducing future losses." ScienceDaily. ScienceDaily, 30 October 2012. <www.sciencedaily.com/releases/2012/10/121030161523.htm>.
University of Illinois College of Agricultural, Consumer and Environmental Sciences. (2012, October 30). Ozone's impact on soybean yield: Reducing future losses. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2012/10/121030161523.htm
University of Illinois College of Agricultural, Consumer and Environmental Sciences. "Ozone's impact on soybean yield: Reducing future losses." ScienceDaily. www.sciencedaily.com/releases/2012/10/121030161523.htm (accessed September 18, 2014).

Share This



More Earth & Climate News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. 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