Can Alcohol Help Thirsty Plants Survive Droughts?
Crops around the world could soon benefit from their own cocktail hour.
From the cassava in your bubble tea to the lettuce in your salad, crops around the world could soon benefit from their own cocktail hour. Ethanol, a form of alcohol derived from corn, has not lived up to its promise as a clean alternative to fossil fuels. Ironically, however, it may play another role in climate resilience—helping crops thrive in drought conditions.
What’s at Stake
Drought drives food insecurity for millions of people worldwide. According to the United Nations, weather extremes were the primary driver of food insecurity in 2020 for 16 million people worldwide. Jobs are also in danger. In much of Africa, over 50 percent of jobs are in agriculture. Closer to home, Honduras lost 50 percent of its corn and bean production in 2019 due to severe drought. These crop failures prompted the displacement of thousands of agricultural workers who had lost their livelihoods. The ability to grow crops in drought conditions would make a world of difference in dry regions like these.
Have a Drink
A research team in Japan is studying the potential of ethanol to help plants handle stress. Motoaki Seki, a plant geneticist at the Japanese research institute RIKEN, reported at the 2020 AAAS conference that giving ethanol to thirsty plants increased their drought tolerance. Seki said ethanol worked for Arabidopsis (a non-crop plant used for research), corn, and rice. Ethanol’s role may seem counterintuitive since alcohol is dehydrating in humans. But when plants endured two weeks without water, those treated with ethanol grew, but those without ethanol barely survived.
An earlier study found that ethanol made Arabidopsis and rice more tolerant of salinity. And acetic acid, which is chemically related to ethanol, improves drought tolerance in corn, wheat, rice, and cassava.
Researchers also tested ethanol on cassava, Seki said. Cassava is an important world crop. It grows in poor soil, is relatively drought-resistant, and can be grown year-round in many climates. Eight million farmers in rural Asia depend on it. Its leaves are used for purposes from livestock feed to biofuel and bioplastic. Cassava even pops up in bubble tea.
Ethanol reduces cassava’s wilting under drought stress, Seki said, by causing the pores in the leaves to close. When pores close, plants are less likely to lose moisture by evaporation.
Research on Arabidopsis reveals how signaling pathways prompted plants to change to handle drought. Such changes included closing pores and increasing the waxiness of leaves.
Ethanol also helped plants tolerate increased temperatures. Seki reported that Arabidopsis treated with ethanol could withstand 122 degrees Fahrenheit. Lettuce could handle 177.5 degrees, and radishes tolerated a whopping 131 degrees.
These remarkable results hold promise for counteracting the effects of increasing drought and heat on food crops. And the world could use some good news.