Researchers from Linköping University have developed an innovative approach to enhance plant growth through an electrically conductive cultivation substrate named eSoil. In a study published in the journal PNAS, the team, led by Associate Professor Eleni Stavrinidou from the Laboratory of Organic Electronics, demonstrated that barley seedlings grown in this conductive “soil” exhibited a remarkable 50% increase in growth over a period of 15 days when their roots were electrically stimulated.
Hydroponics, the method of growing plants without traditional soil, relies on water, nutrients, and a substrate for root attachment. The closed hydroponic system facilitates water recirculation, ensuring each seedling receives precise nutrients. This contrasts with traditional cultivation methods, as it significantly reduces water usage and retains all nutrients within the system.
Hydroponics also allows for vertical cultivation in towers, optimizing space efficiency. While crops like lettuce, herbs, and some vegetables are commonly grown hydroponically, grains, such as barley, are typically excluded. However, this study challenges that norm by showcasing the potential for enhanced barley growth rates through electrical stimulation in a hydroponic environment.
The researchers' eSoil is an electrically conductive cultivation substrate designed specifically for hydroponics. Unlike commonly used non-biodegradable mineral wool, eSoil consists of cellulose, the most abundant biopolymer, mixed with a conductive polymer called PEDOT. This unique combination, while not unprecedented, represents the first application for plant cultivation and creating a plant interface.
Previous studies relied on high-voltage electrical stimulation for root development, but the Linköping researchers' approach distinguishes itself by offering low energy consumption and eliminating high-voltage dangers. Although the exact biological mechanisms behind the enhanced growth are not yet fully understood, the researchers found that seedlings processed nitrogen more effectively under electrical stimulation.
Stavrinidou emphasizes the potential of hydroponics, particularly in areas with limited arable land and challenging environmental conditions. While acknowledging that hydroponics alone cannot solve global food security issues, it presents a valuable solution for more efficient and sustainable agriculture. This breakthrough opens avenues for further research and development in hydroponic cultivation, marking a significant step toward addressing the growing demands of a changing world population and climate.
Source: Linköping University