Featured Research

from universities, journals, and other organizations

Historical Increase In Corn Yield: It's In The Roots

Date:
March 20, 2009
Source:
Crop Science Society of America
Summary:
The extraordinary yield advance within the US Corn Belt over the past century has been a significant agricultural development associated with the breeding of hybrids and increased planting density. A new study examines how the root structure of corn has been one of the key factors in the efficiency of these crops.

One of the most significant developments in agricultural growth in modern times has been the continuous and substantial increase in corn yield over the past 80 years in the U.S. Corn Belt.

Related Articles


This extraordinary yield advance has been associated with both breeding of improved hybrids and the ability to grow them at increased density. In a new study, published in the January-February issue of Crop Science, researchers have investigated the importance of the effects of leaves and roots on this dramatic increase in yield in the U.S. Corn Belt, and have found that the root structure may be the key to understanding how these crops have grown so efficient.

One associated change in the traits of these corn crops has been a more erect leaf angle, which is known to create greater efficiency in converting incident light to biomass. Over the years, detailed studies have shown that the increase in total biomass accumulated through sustained photosynthesis is one of the key factors explaining the yield increase.

However, some studies have also shown that changes in the root system also have an effect, as newer hybrids appear more effective at extracting soil water from deep in the soil profile. There is some evidence suggesting that hybrids with narrower root angle have this capability. It is also plausible that decrease in root angle combined with growing plants at higher density could cause the increase in biomass accumulation. Root systems with improved occupancy of the soil at depth can extract more water to sustain biomass increase.

A team of scientists from Australia and the U.S.A., led by Professor Graeme Hammer of The University of Queensland (UQ), conducted this study on the leaves and roots of corn as part of an Australian Research Council linkage project with Pioneer Hi-Bred International. The project included scientists from UQ, Queensland Department of Primary Industries, and Pioneer.

Their approach involved the use of virtual plant computer simulation technologies. They modified an advanced crop model to take account of known effects on crop growth associated with varying leaf erectness and/or root system architecture. They then simulated consequences on yield for representative sites in the U.S. Corn Belt for a set of “hypothetical hybrids” varying in leaf and root characteristics.

The study revealed that the historical corn yield trend and its association with higher plant density was more likely related to change in root system architecture than to change in leaf erectness. While more erect leaf types could contribute to the effect in some high-yielding situations, changes in root systems to enhance capture of soil water at depth had the dominating effect. Results for simulations conducted for hypothetical hybrids that varied in root system characteristics were found to be consistent with a set of field experiments that reported yield response to density for hybrids released over the past 20 years.

“The use of dynamic crop models helped us to look beyond the clearly visible differences among hybrids in this time series of yield advance,” says Hammer. “It enabled us to focus on the driving processes of crop growth that must be responsible for these effects. It is clear that as we move forward we need to look much harder at root systems and how they capture water.”

In the study, the extra amount of water required for the 6t/ha historical yield increase was estimated as about 270mm. Further research is required to determine whether this has now positioned the corn crop near the limit of water resource availability or whether there remains opportunity for yield advance by further improvement in water capture.


Story Source:

The above story is based on materials provided by Crop Science Society of America. Note: Materials may be edited for content and length.


Journal Reference:

  1. Hammer et al. Can Changes in Canopy and/or Root System Architecture Explain Historical Maize Yield Trends in the U.S. Corn Belt? Crop Science, 2009; 49 (1): 299 DOI: 10.2135/cropsci2008.03.0152

Cite This Page:

Crop Science Society of America. "Historical Increase In Corn Yield: It's In The Roots." ScienceDaily. ScienceDaily, 20 March 2009. <www.sciencedaily.com/releases/2009/03/090316133429.htm>.
Crop Science Society of America. (2009, March 20). Historical Increase In Corn Yield: It's In The Roots. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2009/03/090316133429.htm
Crop Science Society of America. "Historical Increase In Corn Yield: It's In The Roots." ScienceDaily. www.sciencedaily.com/releases/2009/03/090316133429.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. 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:

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