The secret language of funghi
A team of researchers from the Universities of Freiburg and Göttingen and the Helmholtz Zentrum München discovered a correlation between the odorous substances of fungi and the root growth of plants. They determined that the odours of mycorrhizal fungi have a stimulating effect on plant root growth. This discovery is significant for the environment and biotechnology because an enlarged root surface improves a plant’s nutritional and water uptake and therefore its “fitness". The scientists have now published their research in the journal Nature Communications.
Odorous substances play many different roles in nature. Fungi have a characteristic odour, and plants can attract bees or other pollinators through smells. We know that plants regulate their relations to animals through odours, among other things. Plant health, however, depends not only on pollination and defence against consumption, but also on symbiosis with mycorrhizal fungi on its roots. These fungi improve the plant’s nutritional uptake and boost its immune system against harmful fungi .
In order to determine whether plants and mycorrhizal fungi can sense each other through odours, even when they have no direct contact, the researchers cultivated fungi and plants separate from each other but in the same headspace in a laboratory at the University of Göttingen. The result was that the odours of the mycorrhizal fungi caused the plants to sprout many new lateral roots. The scientists at the Helmholtz Zentrum München also found volatile sesquiterpenes in the mycorrhizal fungi. These compounds, which are primarily known for their signalling function in the animal kingdom, are apparently responsible for this growth effect.
The researchers from the University of Freiburg demonstrated that a sesquiterpene called thujopsene, which rarely occurs in nature, is able to stimulate plants to develop lateral roots. BIOSS researcher Prof. Dr. Klaus Palme said, “The signalling pathways in the root tips react to thujopsene and stimulate root growth.” Dr. Franck Ditengou added, “The plants develop a completely new organ. It's as if a human were to grow a new arm." Ditengou and Palme are both members of the Institute of Biology II at the University of Freiburg. Palme is also a member of the Cluster of Excellence of the University of Freiburg BIOSS Centre for Biological Signalling Studies.
Original publication:
Volatile signalling by sesquiterpenes from ectomycorrhizal fungi reprogrammes root architecture.
Ditengou FA, Müller A, Rosenkranz M, Felten J, Lasok H, van Doorn MM, Legué V, Palme K, Schnitzler JP, Polle A.
Nat Commun. 2015 Feb 23;6:6279. doi: 10.1038/ncomms7279.
www.nature.com/ncomms/2015/150223/ncomms7279/full/ncomms7279.html
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