LINKÖPING, Sweden — Scientists have developed an innovative “electronic soil” that significantly boosts crop growth, with barley seedlings growing 50 percent more when their roots receive electrical stimulation through this “eSoil” layer. This breakthrough, spearheaded by researchers from Linköping University in Sweden, focuses on soilless cultivation, commonly known as hydroponics.
“The world population is increasing, and we also have climate change. So it’s clear that we won’t be able to cover the food demands of the planet with only the already existing agricultural methods,” says Professor Eleni Stavrinidou, leader of the Electronic Plants group at the university, in a media release. “But with hydroponics, we can grow food also in urban environments in very controlled settings.”
Her team has developed a specialized electrically conductive cultivation substrate, termed eSoil, designed for hydroponic cultivation. Their research demonstrates that barley seedlings grown in this conductive medium and electrically stimulated at the roots exhibited up to a 50-percent increase in growth over 15 days.
Hydroponic cultivation allows plants to grow without soil, relying only on water, nutrients, and a substrate for root attachment. This closed system facilitates water recycling and precise nutrient delivery, requiring minimal water and keeping all nutrients within the system, a feat not achievable in traditional farming.
The team highlights that hydroponics also supports vertical farming in large towers, optimizing space use. While currently used for crops like lettuce, herbs, and some vegetables, grains have not been commonly grown hydroponically, except as fodder.
In their study, the researchers successfully cultivated barley seedlings hydroponically, enhanced by electrical stimulation.
“In this way, we can get seedlings to grow faster with less resources. We don’t yet know how it actually works, which biological mechanisms that are involved,” Prof. Stavrinidou notes. “What we have found is that seedlings process nitrogen more effectively, but it’s not clear yet how the electrical stimulation impacts this process.”
Typically, hydroponics employs mineral wool as a substrate, a non-biodegradable material produced through energy-intensive processes. However, the team’s eSoil is a blend of cellulose and a conductive polymer called PEDOT, marking its first use in plant cultivation and creating a plant interface in this way.
Unlike previous research that used high voltage for root stimulation, this new “soil” has the advantage of low energy consumption and no high voltage risks.
“We can’t say that hydroponics will solve the problem of food security. But it can definitely help particularly in areas with little arable land and with harsh environmental conditions.” Prof. Stavrinidou concludes.