Scientists find surprising way to keep your plants alive in a drought

The morning after a night out often comes with dehydration-induced headaches and a parched mouth, with paracetamol and a gallon of water the only cure.

But scientists have now found that alcohol has the opposite effect on plants and it helps keep water in as opposed to flushing it out.

Researchers say the chemical could help farmers, and their crops, beat drought in the future.

Academics from Japan have found that ethanol - the intoxicating compound found in beer and wine - helps make plants more drought-resistant and better able to survive an extended bout of dry weather.

Experiments found that getting plants drunk helps crops flourish while sober plants become shrunken and dishevelled.

Plants lose water through their leaves when pores called stomata open to allow it to escape, but ethanol helps keep these closed, the scientists found, thus improving water retention.

In the trial, plants were grown in normal conditions for a fortnight and were regularly watered before the team then cut off irrigation. The soil of half of the crops was treated with ethanol for three days while the rest were left as normal.

Three-quarters of rice and wheat plants given the alcohol treatment survived when watered again two weeks later, but just one in 20 of the untreated plants sprung back to life.

Uses alcohol for fuel

A follow-up lab experiment on a well-studied cress species revealed that treatment with alcohol closes stomata, helping trap water in the leaves.

Genetic analysis of the plant also showed that plants switch on drought-fighting genes when ethanol is picked up by the roots.

This not only stopped the loss of water through the vent-like stomata but also saw the plant activate a process where it actually uses the alcohol for fuel.

Photosynthesis, the vital process that plants use to make energy from sunlight, needs water, but in the study, published in the journal Plant and Cell Physiology, the team found the plant can do this with ethanol instead in times of drought to further conserve dwindling supplies while also still making energy.

This metabolising of alcohol also means that shops would not be stocked with alcohol-infused foods if an alcohol-aided plant was harvested as it would have long ago been turned into energy by the plant.

“We find that treating common crops such as wheat and rice with exogenous ethanol can increase crop production during drought,” said Dr Motoaki Seki, study lead author from RIKEN.

“This is likely via changes in the metabolomic and transcriptomic profiles that regulate the drought-stress response.”

In the paper, the team states that ethanol is “an inexpensive and environmentally-friendly chemical”, with Dr Seki adding that getting plants drunk is “a cheap and easy way to increase our crop yield”.

‘No serious concerns’

Dr Seki told The Telegraph that ethanol is unlikely to have any negative effects if added to crop fields, adding that he has “no serious concerns for the use of low concentration of ethanol”.

However, he added that “we need to analyse the environmental effect of ethanol spray on the field” before it can be widely recommended on a commercial scale.

This approach, the team says, is not the only way for farmers to overcome drought. Another popular avenue is that of genetic modification, where scientists fiddle with the DNA of a cultivar to make it better at withstanding aridity - such as by turning on genes to close stomata.

Ten of the country’s 14 regions are now officially in a drought and August is set to be drier than normal, with less than half the rainfall predicted than in an average year, falling to just 29 per cent in the South-East, according to the Met Office.

By next week, six water companies serving almost 30 million customers will have implemented a hosepipe ban across the country after England’s driest July in 50 years.