Nav: Home

How plants react to fungi

October 07, 2019

Plants are under constant pressure from fungi and other microorganisms. The air is full of fungal spores, which attach themselves to plant leaves and germinate, especially in warm and humid weather. Some fungi remain on the surface of the leaves. Others, such as downy mildew, penetrate the plants and proliferate, extracting important nutrients. These fungi can cause great damage in agriculture.

The entry ports for some of these dangerous fungi are small pores, the stomata, which are found in large numbers on the plant leaves. With the help of specialised guard cells, which flank each stomatal pore, plants can change the opening width of the pores and close them completely. In this way they regulate the exchange of water and carbon dioxide with the environment.

Chitin covering reveals the fungi

The guard cells also function in plant defense: they use special receptors to recognise attacking fungi. A recent discovery by researchers led by the plant scientist Professor Rainer Hedrich from Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany, has shed valuable light on the mechanics of this process.

"Fungi that try to penetrate the plant via open stomata betray themselves through their chitin covering," says Hedrich. Chitin is a carbohydrate. It plays a similar role in the cell walls of fungi as cellulose does in plants.

Molecular details revealed

The journal eLife describes in detail how the plant recognizes fungi and the molecular signalling chain via which the chitin triggers the closure of the stomata. In addition to Hedrich, the Munich professor Silke Robatzek from Ludwig-Maximilians-Universität was in charge of the publication. The molecular biologist Robatzek is specialized in plant pathogen defense systems, and the biophysicist Hedrich is an expert in the regulation of guard cells and stomata.

Put simply, chitin causes the following processes: if the chitin receptors are stimulated, they transmit a danger signal and thereby activate the ion channel SLAH3 in the guard cells. Subsequently, further channels open and allow ions to flow out of the guard cells. This causes the internal pressure of the cells to drop and the stomata close - blocking entry to the fungus and keeping it outside.

Practical applications in agricultural systems

The research team has demonstrated this process in the model plant Arabidopsis thaliana (thale cress). The next step is to transfer the findings from this model to crop plants. "The aim is to give plant breeders the tools they need to breed fungal-resistant varieties. If this succeeds, the usage of fungicides in agriculture could be massively reduced," said Rainer Hedrich.
-end-


University of Würzburg

Related Fungi Articles:

Plants and fungi together could slow climate change
A new global assessment shows that human impacts have greatly reduced plant-fungus symbioses, which play a key role in sequestering carbon in soils.
Make fungi think they're starving to stop them having sex, say scientists
Tricking fungi into thinking they're starving could be the key to slowing down our evolutionary arms race with fungal pathogens, as hungry fungi don't want to have sex.
How plants react to fungi
Using special receptors, plants recognize when they are at risk of fungal infection.
Clostridium difficile infections may have a friend in fungi
The pathogen Clostridium difficile, which causes one of the most common hospital-acquired infections in the United States, may have accomplices that until now have gone largely unnoticed.
A 'crisper' method for gene editing in fungi
A team of researchers from Tokyo University of Science, Meiji University, and Tokyo University of Agriculture and Technology, led by Professor Takayuki Arazoe, has recently established a series of novel strategies to increase the efficiency of targeted gene disruption and new gene 'introduction' using the CRISPR/Cas9 system in the rice blast fungus Pyricularia (Magnaporthe) oryzae.
Are no-fun fungi keeping fertilizer from plants?
Research explores soil, fungi, phosphorus dynamics.
How fungi influence global plant colonisation
The symbiosis of plants and fungi has a great influence on the worldwide spread of plant species.
Fluconazole makes fungi sexually active
Under the influence of the drug fluconazole, the fungus Candida albicans can change its mode of reproduction and thus become even more resistant.
Soil fungi secrete an antibiotic with antitumor activity
A team of scientists from I.M. Sechenov First Moscow State Medical University (MSMU) together with their colleagues isolated a peptide named emericellipsin A from soil fungi.
Individual lichens can have up to three fungi, study shows
Individual lichens may contain up to three different fungi, according to new research from an international team of researchers.
More Fungi News and Fungi Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.