Nav: Home

Mechanism behind plant withering clarified

April 21, 2016

A research team led by Associate Professor Miyake Chikahiro and PhD student Takagi Daisuke from the Kobe University Graduate School of Agricultural Science have reproduced the reaction in which harmful reactive oxygen species are created during plant photosynthesis, and clarified a mechanism behind plant withering. This discovery could help to ensure stable food supplies by cultivating plants that can withstand environmental stresses such as global warming. The findings were published on March 2 in the online version of Plant Physiology.

The majority of plants depend on photosynthesis as an essential energy source. However, when the light energy necessary for photosynthesis is absorbed in excess, harmful reactive oxygen species (ROS) are produced. In most cases plants use enzymes to deal with these reactive oxygen species. If plants are exposed to environmental stresses such as lack of water or excess minerals, their ability to photosynthesize is reduced, the ROS removal mechanism cannot keep up with the ROS produced from excess light energy, and plants wither and die. Researchers already knew that ROS are produced within chloroplasts in plant cells, but the exact location and the mechanism behind this were unclear.

Professor Miyake's research group extracted chloroplasts and thylakoid membranes from leaves, and exposed them to excess light using repetitive short-pulse illumination. As a result of this treatment, a particle known as "P700" which absorbs light energy within photosystem I¹ stopped functioning, and three types of reactive oxygen species were produced: superoxide radicals (O2 -), hydroxyl radicals (OH?) and singlet oxygen (1O2). They further confirmed that by limiting the flow of electrons to photosystem I the production of reactive oxygen species was suppressed.

Due to factors such as global warming, Earth's natural environment is becoming increasingly inhospitable for plant life. "By revealing the mechanism for the production of ROS and part of its regulatory mechanism, there are future possibilities for ensuring a stable food supply despite global warming," said Professor Miyake. "The next step is to reveal the regulatory mechanism for ROS on a molecular level."
-end-
¹Photosystem I (PSI): a protein complex in thylakoid membranes that plays a major role in plant photosynthesis

Kobe University

Related Global Warming Articles:

A new study provides a solid evidence for global warming
The new study allows a more accurate assessment of how much heat has accumulated in the ocean (and Earth) system.
Global warming hiatus disproved -- again
UC Berkeley scientists calculated average ocean temperatures from 1999 to 2015, separately using ocean buoys and satellite data, and confirmed the uninterrupted warming trend reported by NOAA in 2015, based on that organization's recalibration of sea surface temperature recordings from ships and buoys.
Report reassesses variations in global warming
Experts at the European Centre for Medium-Range Weather Forecasts (ECMWF) have issued a new assessment of temperature trends and variations from the latest available data and analyses.
Clouds are impeding global warming... for now
Lawrence Livermore National Laboratory researchers have identified a mechanism that causes low clouds -- and their influence on Earth's energy balance -- to respond differently to global warming depending on their spatial pattern.
Global warming's next surprise: Saltier beaches
Batches of sand from a beach on the Delaware Bay are yielding insights into the powerful impact of temperature rise and evaporation along the shore that are in turn challenging long-held assumptions about what causes beach salinity to fluctuate in coastal zones that support a rich network of sea creatures and plants.
Could global warming's top culprit help crops?
A new study tries to disentangle the complex question of whether rising amounts of carbon dioxide in the air might in some cases help crops.
Evaporation for review -- and with it global warming
The process of evaporation, one of the most widespread on our planet, takes place differently than we once thought -- this has been shown by new computer simulations carried out at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw.
Researchers reveal when global warming first appeared
Human caused climate change is increasingly apparent today through multiple lines of evidence.
1,800 years of global ocean cooling halted by global warming
Prior to the advent of human-caused global warming in the 19th century, the surface layer of Earth's oceans had undergone 1,800 years of a steady cooling trend, according to a new study in the Aug.
Global sea levels have risen 6 meters or more with just slight global warming
A new review analyzing three decades of research on the historic effects of melting polar ice sheets found that global sea levels have risen at least six meters, or about 20 feet, above present levels on multiple occasions over the past three million years.

Related Global Warming Reading:

The Politically Incorrect Guide to Climate Change (The Politically Incorrect Guides)
by Marc Morano (Author)

Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming
by Paul Hawken (Editor), Tom Steyer (Editor)

The Sixth Extinction: An Unnatural History
by Elizabeth Kolbert (Author)

The Uninhabitable Earth: Life After Warming
by David Wallace-Wells (Author)

Climate Change: What Everyone Needs to Know®
by Joseph Romm (Author)

Global Warming-Alarmists, Skeptics and Deniers: A Geoscientist Looks at the Science of Climate Change
by G. Dedrick Robinson (Author), Gene D. Robinson III (Author)

A Global Warming Primer: Answering Your Questions About The Science, The Consequences, and The Solutions
by Jeffrey Bennett (Author)

Climate Change: The Science of Global Warming and Our Energy Future
by Edmond Mathez (Author), Jason Smerdon (Author)

The Thinking Person's Guide to Climate Change
by Robert Henson (Author)

Climate Change: The Facts
by J.Abbot (Author), J.S. Armstrong (Author), A.Bolt (Author), R.Carter (Author), R.Darwall (Author), J.Delingpole (Author), C.Essex (Author), S.Franks (Author), K.Green (Author), D.Laframboise (Author), N.Lawson (Author), B.Lewin (Author), R.Lindzen (Author), J.Marohasy (Author), R.McKitrick (Author), P.Michaels (Author), A.Moran (Author), J.Nova (Author), G.Paltridge (Author), I.Plimer (Author), W.Soon (Author), M.Steyn (Author), A.Watts (Author), Alan Moran (Editor)

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Bias And Perception
How does bias distort our thinking, our listening, our beliefs... and even our search results? How can we fight it? This hour, TED speakers explore ideas about the unconscious biases that shape us. Guests include writer and broadcaster Yassmin Abdel-Magied, climatologist J. Marshall Shepherd, journalist Andreas Ekström, and experimental psychologist Tony Salvador.
Now Playing: Science for the People

#514 Arctic Energy (Rebroadcast)
This week we're looking at how alternative energy works in the arctic. We speak to Louie Azzolini and Linda Todd from the Arctic Energy Alliance, a non-profit helping communities reduce their energy usage and transition to more affordable and sustainable forms of energy. And the lessons they're learning along the way can help those of us further south.