Featured Research

from universities, journals, and other organizations

Higher carbon dioxide levels mean poorer wheat quality

Date:
December 10, 2012
Source:
University of Gothenburg
Summary:
Rising levels of atmospheric carbon dioxide have a negative impact on the protein content of wheat grain and thus its nutritional quality.

Rising levels of atmospheric carbon dioxide have a negative impact on the protein content of wheat grain and thus its nutritional quality. This is the finding of researchers at the University of Gothenburg, Sweden, in a recently published study in the journal Global Change Biology.

Elevated levels of atmospheric carbon dioxide stimulate the photosynthesis and growth of most plants. However, unless plants increase their uptake of nutrients to a corresponding degree, their yields will have a lower nutritional value. A lower level of the nutrient nitrogen results in a lower protein content, and thus poorer nutritional quality.

"Protein content is the most important quality aspect for crops, with implications for both nutritional value and the baking properties of the grain," explains Hεkan Pleijel, Professor of Environmental Science at the University of Gothenburg's Department of Biological and Environmental Sciences.

Researchers Hεkan Pleijel and Johan Uddling have summarized the way in which experimentally elevated carbon dioxide levels affect the harvest index and protein content of wheat. The study includes 43 field experiments with 17 different varieties of wheat, carried out in ten countries across four continents. The results of the study are unequivocal:

"Elevated carbon dioxide levels often increase the size of the grain yield, but also lead to a reduction in quality in the form of lower protein content," says Professor Pleijel.

Wheat -- together with rice -- is the world's most important crop in quantitative terms. Wheat grain is also unusually rich in protein, and wheat is the crop that provides the human race with the most protein. Reduced protein content as a result of elevated carbon dioxide levels is therefore a serious negative consequence of ongoing atmospheric change.

One reason why the protein content of wheat grain drops as carbon dioxide levels rise is that nitrogen uptake does not keep pace with the increased growth of the wheat grain -- a kind of dilution effect. However, elevated carbon dioxide levels reduce the protein content of wheat even when the size of the wheat yield is unaffected.

"This indicates that carbon dioxide has a negative impact on plants' ability to absorb nitrogen," continues Professor Pleijel. "This is a novel and unexpected finding, and is something we need to study in greater depth in order to understand the causes."

Laboratory studies have shown that elevated carbon dioxide levels can disrupt the process whereby plants convert the inorganic nitrogen molecule nitrate into the forms of nitrogen found in proteins.

Johan Uddling and Professor Pleijel are currently investigating whether the effects they have demonstrated in wheat are also seen in other crops.

"Our results indicate that reduced nitrogen and protein content as a result of elevated carbon dioxide levels is a general response in crops, and cannot be countered simply through increased fertilization," adds Uddling.

The overall positive effect of elevated carbon dioxide levels on grain yield therefore has a downside in the form of a reduction in the nutritional quality of our most important foodstuff.

"This is a serious consequence of rapidly rising global carbon dioxide levels on global food security," concludes Professor Pleijel.


Story Source:

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


Journal Reference:

  1. Hεkan Pleijel, Johan Uddling. Yield vs. Quality trade-offs for wheat in response to carbon dioxide and ozone. Global Change Biology, 2012; 18 (2): 596 DOI: 10.1111/j.1365-2486.2011.2489.x

Cite This Page:

University of Gothenburg. "Higher carbon dioxide levels mean poorer wheat quality." ScienceDaily. ScienceDaily, 10 December 2012. <www.sciencedaily.com/releases/2012/12/121210080631.htm>.
University of Gothenburg. (2012, December 10). Higher carbon dioxide levels mean poorer wheat quality. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2012/12/121210080631.htm
University of Gothenburg. "Higher carbon dioxide levels mean poorer wheat quality." ScienceDaily. www.sciencedaily.com/releases/2012/12/121210080631.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