Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Light green plants save nitrogen without sacrificing photosynthetic efficiency

21.11.2017

The top leaves of crops absorb far more light than they can use, starving lower leaves of light. Scientists designed plants with light green leaves with hopes of allowing more light to penetrate the crop canopy and increase overall light use efficiency and yield. This strategy was tested in a recent modeling study that found leaves with reduced chlorophyll content do not actually improve canopy-level photosynthesis, but instead, conserve a significant amount of nitrogen that the plant might be able to reinvest to improve light use efficiency and increase yield.

"Leaves up at the top of the canopy are really greedy--they absorb a lot of light and don't let much down to their brothers and sisters below them," said Berkley Walker, an Alexander von Humboldt Postdoctoral Fellow at the University of Düsseldorf, who led this work supported by Realizing Increased Photosynthetic Efficiency (RIPE).


Scientists have designed plants with light green leaves to allow more light to penetrate the crop canopy to increase photosynthesis and yield; however, models show these plants likely require less nitrogen and photosynthesis is hardly affected.

Credit: Claire Benjamin/University of Illinois

"Leaves up at the top aren't very efficient with that light energy, but the leaves at the bottom are very efficient. So, if you could just take some of that light that's being hogged up at the top, and move it down deeper into the canopy, theoretically, you'd have a more efficient canopy."

Published in Plant Physiology, researchers tested this idea using a computer simulation incorporating data from nearly 70 varieties of soybeans with varying levels of chlorophyll from the U.S. Department of Agriculture germplasm bank. They found that plants with 20 percent less chlorophyll theoretically require 9 percent less nitrogen with no penalty to carbon gain (biomass) and yield.

"The simulation reveals that the complex interior structure of leaves causes the light to bounce around so much that the light has the same probability of going up as it does going down," said RIPE Deputy Director Don Ort, a physiologist with the USDA/ARS Photosynthesis Research Unit and the Robert Emerson Professor of Plant Biology and Crop Sciences at the Carl R. Woese Institute for Genomic Biology at the University of Illinois. "When we decrease chlorophyll, more light is lost to reflection, and we don't get the full benefits of getting light deeper into the canopy where it can be absorbed."

Next, they are exploring if these nitrogen savings could be used to fix other photosynthetic bottlenecks as well as other ways to increase light penetration into the canopy.

"It's not case closed on light green plants, but the strategy is going to be a little more nuanced than just putting plants out there with lower chlorophyll content," Walker said. "We need to explore if light green can be combined with changes in leaf architecture or if we can re-engineer leaves to be thinner to reduce light reflectance and improve transmittance."

Other RIPE-funded work that modeled a decrease in chlorophyll content in rice found that reallocating these nitrogen savings could improve canopy photosynthesis and nitrogen use efficiency by 30 percent. According to collaborator Xinguang Zhu of the Chinese Academy of Sciences, "Manipulation of leaf chlorophyll content is one exciting option to explore both increased energy and light use efficiencies. This study shows that gaining the desired benefit requires a more thorough understanding of the leaf optical properties and nitrogen distribution patterns among photosynthetic proteins in a leaf."

###

Realizing Increased Photosynthetic Efficiency (RIPE) is engineering staple food crops to more efficiently turn the sun's energy into food to sustainably increase worldwide food productivity, with support from the Bill & Melinda Gates Foundation, the Foundation for Food and Agriculture Research, and the U.K. Department for International Development.

RIPE is led by the University of Illinois in partnership with the University of Essex, Lancaster University, Australian National University, Chinese Academy of Sciences, Commonwealth Scientific and Industrial Research Organisation, Louisiana State University, University of California, Berkeley, and the USDA Agricultural Research Service.

The paper "Chlorophyll can be reduced in crop canopies with little penalty to photosynthesis" was published in Plant Physiology (doi: doi.org/10.1104/pp.17.01401). Co-authors include Darren T Drewry, Jet Propulsion Laboratory; Rebecca A Slattery, USDA-ARS; Andy VanLoocke, Iowa State University; and Young B. Cho, University of Illinois.

Media Contact

Claire Benjamin
claire@illinois.edu
217-244-0941

 @IGBIllinois

http://www.igb.uiuc.edu 

Claire Benjamin | EurekAlert!

Further reports about: Biology Genomic Biology Photosynthesis USDA canopy green plants leaves nitrogen photosynthetic

More articles from Agricultural and Forestry Science:

nachricht Researchers discover natural product that could lead to new class of commercial herbicide
16.07.2018 | UCLA Samueli School of Engineering

nachricht Advance warning system via cell phone app: Avoiding extreme weather damage in agriculture
12.07.2018 | Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e.V.

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>