Plants use underground networks to warn of enemy attack

May 10, 2013 by Alex Peel
Plants use underground networks to warn of enemy attack
Aphid infestation.

Plants use underground fungal networks to warn their neighbours of aphid attack, UK scientists have discovered.

The research, published today in Ecology Letters, changes our understanding of how things interact with one another.

If crops can be managed in a way that exploits the natural communication channel, it could also provide a new weapon in the battle against .

'Our understanding of has not considered the fact that plants are interconnected in this way,' says Dr David Johnson of the University of Aberdeen, who led the study. 'It could have major implications for our understanding of how one organism affects another.'

The team grew in groups of five, allowing three in each group to grow underground networks of mycelia, thread-like fungi that grow from one set of roots to another. They kept two plants free of the fungal links.

They then infested one of the plants in each group with , triggering the release of a suite of chemicals designed to repel aphids and attract , one of the pest's predators.

Remarkably, plants which were not under attack themselves, but which were wired to the victim by the underground fungal network, also began to produce the defensive chemical's.

Unconnected plants didn't get the warning, and remained vulnerable to aphid attack.

Previous research has shown that plants can communicate chemically through the air, but the scientists covered the plants with bags to rule out above-ground signalling.

'We knew that plants produce when attacked, and we knew they communicate danger to each other above ground,' says Johnson. 'Now we know that they communicate danger through these underground fungal networks as well.'

Plants use underground networks to warn of enemy attack
Fungal infection.

'Connected plants that weren't infested by the aphids behaved as though they were. We don't quite know the mechanism of communication, but it's likely to be a .'

The mycelium fungus, a white, stringy material that you might find on a rotting apple, forms a give and take relationship with plants known as symbiosis. In exchange for the carbon it needs, the fungus spreads through the soil allowing the plant to draw in nutrients from a wider area.

The roots of virtually all groups of plants, including important food crops such as wheat, rice, maize and barley, are colonised by symbiotic fungi.

According to another of the study's authors, Professor John Pickett of Rothamsted Research, the underground could open the door for a new, natural and sustainable way of tackling pests and diseases.

'In a field of plants that have some inducible resistance to aphids, we could use a plant that's susceptible to aphid attack to 'switch on' the defence mechanism through the natural underground connection,' he says.

'Aphids affect all higher-latitude agricultural regions, including the UK, the EU, North America, and North East Asia and there's the potential to deal with other pests and diseases, in other regions, in a similar way.'

Explore further: Endangered hammerhead shark found migrating into unprotected waters

More information: Babikova, Z. et al. Underground signals carried through common mycelial networks warn neighbouring plants of aphid attack, Ecology Letters, 2013. DOI: 10.1111/ele.12115

Related Stories

Plants 'talk' to plants to help them grow

May 06, 2013

Having a neighborly chat improves seed germination, finds research in BioMed Central's open access journal BMC Ecology. Even when other known means of communication, such as contact, chemical and light-mediated signal ...

Plant defenses: Maize knows how to identify its target

Mar 19, 2013

Insect or microbe: plants recognize their attackers and respond by producing specific internal signals that induce the appropriate chemical defenses. That is the main conclusion of a study at the Center for ...

Ladybirds thrive on organic aphids

Jul 06, 2012

Ladybird larvae that eat prey raised on organically-grown crops are more likely to survive than those eating aphids raised on crops grown with conventional fertiliser, a new experiment shows.

Gene silencing set to boost agricultural yields

Apr 30, 2013

Researchers from Murdoch University have developed an environmentally friendly 'gene silencing' method to control Root Lesion Nematodes, plant pathogens known to reduce crop yields in major crops such as whea ...

Recommended for you

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.