Get touchy feely with plants

Sep 16, 2013

Forget talking to plants to help them grow, gently rubbing them with your fingers can make them less susceptible to disease, a paper in the open access journal BMC Plant Biology reveals.

Gently rubbing the leaves of thale cress plants (Arabidsopsis thaliana) between thumb and forefinger activates an innate , Floriane L'Haridon and colleagues report. Within minutes, occur, causing the plant to become more resistant to Botrytis cinerea, the fungus that causes grey mould.

Rubbing the leaves is a form of mechanical stress. Plants frequently have to deal with mechanical stress, be it caused by rain, wind, animals or even other plants. Trees growing on windy shorelines, for example, sometimes respond by developing shorter, thicker trunks.

But plants also respond to more delicate forms of mechanical stress, such as touch. Some responses are obvious – the snapping shut of a Venus fly trap, the folding leaflets of a touched touch-me-not plant (Mimosa pudica) – whilst some are more discrete. Plants also launch an arsenal of 'invisible' responses to mechanical stress, including changes at the molecular and biochemical level.

Rubbing the thale cress leaves triggered a host of internal changes. Genes related to mechanical stress were activated. Levels of reactive oxygen species increased. And the protective outer layer of the leaf became more permeable, presumably to aid the escape of various biologically active molecules that were detected and which are thought to contribute to the observed . This data could also suggest that the is perceived by mechano-sensors that subsequently initiate resistance.

Similar effects occur when plants are physically wounded. Team members previously showed how physically wounding thale cress increases levels of reactive , also triggering a strong, transient immunity to the grey mould fungus. Here they show basically the same thing, but in response to an extremely gentle form of wounding - mechanical stimulation by touch - that unlike wounding, leaves cells intact.

Wounding and rubbing exemplify how plants can react to a situation that in principle could cause them to become more vulnerable. Instead, they react to touch by deploying a carefully-orchestrated defence response, an evolutionary skill that that presumably boosts survival.

Explore further: Research helps steer mites from bees

add to favorites email to friend print save as pdf

Related Stories

A bit touchy: Plants' insect defenses activated by touch

Apr 09, 2012

A new study by Rice University scientists reveals that plants can use the sense of touch to fight off fungal infections and insects. The study, which will be published in the April 24 issue of Current Biology, finds ...

Scientists find how plants grow to escape shade

Apr 15, 2012

Mild mannered though they seem, plants are extremely competitive, especially when it comes to getting their fair share of sunlight. Whether a forest or a farm, where plants grow a battle wages for the sun's ...

How plants chill out

May 21, 2012

Plants elongate their stems when grown at high temperature to facilitate the cooling of their leaves, according to new research from the University of Bristol published today in Current Biology. Understanding why plants alter ...

A tale of two fungi

Mar 05, 2013

(Phys.org) —In the February issue of New Phytologist, Tulane University biologists examine why leaf-cutting ants target some plants and avoid others, concluding that high levels of friendly fungi in the ...

Drought response identified in potential biofuel plant

Jul 15, 2013

Drought resistance is the key to large-scale production of Jatropha, a potential biofuel plant—and an international group of scientists has identified the first step toward engineering a hardier variety.

Recommended for you

Research helps steer mites from bees

Sep 19, 2014

A Simon Fraser University chemistry professor has found a way to sway mites from their damaging effects on bees that care and feed the all-important queen bee.

User comments : 0