The green leaves of plants use the energy of sunlight to make sugar by combining water with carbon dioxide from the atmosphere. This sugar fuels the plant’s growth, but scientists in the University’s Department of Biology discovered that some of it goes straight to the roots to feed a surprising variety of microbes.
A study led by Professor Peter Young, of the Department of Biology at York and Dr Philippe Vandenkoornhuyse of the University of Rennes in France is published in the latest issue of the Proceedings of the National Academy of Sciences of the USA (PNAS).
In the carbon cycle, plants remove carbon dioxide (a greenhouse gas) from the atmosphere. Eventually, the carbon compounds that plants make are “eaten” by microbes and animals, which release carbon dioxide back into the atmosphere. The rapid cycling demonstrated by the new research is an important link in this process.
Professor Young said: “Our research identifies microbes in roots that create a short cut in the carbon cycle. This is an important development given current interest in reducing outputs of carbon dioxide and the ‘carbon trading’ that is intended to help this.”
The researchers traced the path of the carbon by replacing the normal carbon dioxide in the air around the plants with a version made with C-13, a natural, non-radioactive form of carbon that is slightly heavier than the usual kind. Within hours, microbes in the roots were feeding on sugars laden with C-13 and using it to build their own cells.
The newly-made molecules of DNA and RNA produced by the microbes could be separated from pre-existing ones because the C13 made them heavier. DNA and RNA are large molecules that carry genetic information about the organisms that made them, so it was possible to identify the microbes that made those heavy molecules. These were the “greedy” ones that were consuming the largest share of the sugars provided by the plant.
Professor Young said: “There are rich communities of microbes growing in or around the roots of all plants growing in normal soil. Most do no harm to the plant, and some are very beneficial to it. We looked at two sorts of microbe: bacteria and mycorrhizal fungi.”
The researchers found a high diversity of both types of microbe inside the roots of grass or clover plants growing in a pasture, but the “heavy” label revealed that some of these were growing much more actively than others.
Professor Young added: “It is these active organisms that are important because they are turning sugar back into carbon dioxide, which is released into the atmosphere. We were astonished at the wide variety of active bacteria that we discovered. Many of them had not been seen in plant roots before, and we have no idea how they may affect plant growth.”
The role of mycorrhizal fungi is better known. They are particularly important in carbon cycling, because they pump the carbon compounds out of the root into a massive network of fine fungal filaments in the soil, where it becomes available to other microbes and also to larger soil organisms like worms, mites and insects. In return, the fungus gathers phosphorus from the soil and delivers it to the plant, helping the plant to grow better. The research confirmed that there were many different fungi in the roots of each plant, but revealed, for the first time, which of these fungi were most active.
David Garner | alfa
Bioinvasion on the rise
15.02.2017 | Universität Konstanz
Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
17.02.2017 | Medical Engineering
17.02.2017 | Medical Engineering
17.02.2017 | Health and Medicine