Featured Research

from universities, journals, and other organizations

Roots key to second Green Revolution

Date:
February 23, 2010
Source:
Penn State
Summary:
Root systems are the basis of the second Green Revolution, and the focus on beans and corn that thrive in poor growing conditions will help some of the world's poorest farmers, according to a plant scientist.

Simulation of bean root systems showing how altered root growth angles lead to deep or shallow soil exploration.
Credit: Jonathan Lynch, Penn State

Root systems are the basis of the second Green Revolution, and the focus on beans and corn that thrive in poor growing conditions will help some of the world's poorest farmers, according to a Penn State plant scientist.

"Africans missed the Green Revolution of the '60s because they typically do not eat wheat and rice, which was its focus," said Jonathan Lynch, professor of plant nutrition.

The First Green Revolution was an effort to create dwarf wheat and rice plants that could prosper with more fertilizer. While this approach worked in Asia and other places where rice and wheat are the staple crops, it did not affect Africa.

"Just as the Green Revolution was based on crops responsive to high soil fertility, the Second Green Revolution will be based on crops tolerant of low soil fertility," Lynch told attendees at the annual meeting of the American Association for the Advancement of Science, Feb. 20 in San Diego, Calif.

With no money, no credit, no markets and a population that cannot read, African subsistence farmers need another, less expensive and less complicated approach -- one that does not require irrigation or fertilization.

"African farmers are poor and fertilizers take fossil fuels to manufacture," said Lynch. "A pound of fertilizer in Malawi costs ten times more than it does in Europe. With an average daily wage of $.80 it is not realistic for African farmers to buy fertilizer."

For 25 years, Lynch worked on beans that can thrive in low phosphorus soils. Phosphorus is the nutrient most important for healthy bean plants. The key to this approach is the root system. Phosphorus in the soil remains near the surface, but most commercially available bean plants had roots that grow down deep into the soil, swiftly growing past the phosphorus rich zone.

Using standard plant breeding techniques, Lynch and colleagues produced bean plants with shallow, spreading roots that flourish in infertile soil. He also chose plants that produced more root hairs. The shallow roots were an improvement of about 600 percent in production and the increased root hairs were an improvement of 250 percent.

"People were skeptical about this approach," said Lynch. "They questioned whether growing beans without added phosphorus would simply increase soil degradation."

In fact, while the plants do remove phosphorus from the soil, more phosphorus was being lost to erosion due to sloping fields. Healthy, leafy plants prevented erosion, and the soils were generally better than with poor quality deep-rooted plants. Decreasing erosion by two to three times easily made up for what the plants removed.

After his work with beans, the McKnight Foundation asked him to look at soybeans.

"Our partners in China now have seven soybean lines with shallow root systems that are good for poor soils low in phosphorus," said Lynch.

Because any shallow rooted plant is more susceptible to drought, Lynch suggests that the shallow-rooted beans be mixed with deep-rooted plants to ensure some harvest in every season.

"We are not creating a monoculture; multilines of seeds are actually the best approach," said Lynch.

While beans are an important crop in poor countries, corn is the biggest crop in the U.S. and in the world. Corn or maize requires an enormous amount of nitrogen to grow properly and half the nitrogen is wasted.

"The plants do not take it up and it ends up in the groundwater," said Lynch. "Or it becomes nitrogen oxides, which are 300 times more detrimental greenhouse gases than carbon dioxide.

"If we can move corn from being 50 percent efficient with nitrogen to 60 percent efficient we will save billions of dollars and there will be an environmental gain as well."

Because nitrogen moves very quickly through the soil, it outpaces maize roots. Lynch looked for maize that had rapid deep root development, but large amounts of roots are costly for plants to manufacture.

"We knew that in flooded areas plant roots develop aerenchyma," said Lynch. "Roots with these hollowed out portions are less costly metabolically for the plants to produce."

Roots with aerenchyma are also better during droughts because they can produce deeper roots to acquire moisture from dry soils.

Currently, Lynch has about 20 people looking at plant roots from thousands of maize lines. Once the researchers identify the best lines, genetic evaluation will identify the key traits for this type of root, with the hope of developing maize lines that are better at using nitrogen and more drought tolerant.

The National Science Foundation, U.S. Department of Agriculture, McKnight Foundation, Howard G. Buffet Foundation, Monsanto, U.S. Agency for International Development supported this work.


Story Source:

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


Cite This Page:

Penn State. "Roots key to second Green Revolution." ScienceDaily. ScienceDaily, 23 February 2010. <www.sciencedaily.com/releases/2010/02/100220184319.htm>.
Penn State. (2010, February 23). Roots key to second Green Revolution. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2010/02/100220184319.htm
Penn State. "Roots key to second Green Revolution." ScienceDaily. www.sciencedaily.com/releases/2010/02/100220184319.htm (accessed July 31, 2014).

Share This




More Plants & Animals News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. 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