Source**: Thor Balkhed).
A new conductive "soil" could make hydroponic agriculture more productive and help ensure a sustainable new source of human food.
We can make the seedlings grow faster with fewer resources," says Eleni St**Rinidou, head of the Link Ping University team that developed this new substrate.
Challenge:Most of the world is perpetually in the grip of a food crisis. It is estimated that in 2022 there will be 73.5 billion people are chronically undernourished, a figure that has increased by 1 since 20192.2 billion is a major setback after decades of progress. Efforts to expand food ** may face new pressures in the future.
The world's population is increasing, and we also have climate change," Stavrinidoo said. "Therefore, it is clear that we will not be able to meet the food needs of the planet with existing agricultural methods alone. ”
The idea: hydroponic agriculture – a technique of growing plants in water rather than soil – could help the world meet some of the food needs of the future.
Not only can it be used for farming in areas where arable land is lacking, but it can also be used with hydroponic systems with lights to grow plants indoors. Pallet crops can then be layered vertically, allowing more food to be grown in one area than traditional farming.
"We can't say that hydroponics will solve food security, but it can certainly help, especially in areas with little arable land and poor environmental conditions," Stavrinidoo said. ”
The biggest challenge in indoor hydroponic farming is cost – it's much cheaper to get the sun to provide light than it is to power LEDs – so finding ways to make this process more efficient is key to helping it reach its potential.
St**Rinidou's team has now developed a new substrate for hydroponic farming. In hydroponic systems, this is the material to which the roots of the plant are attached, not the soil, and the standard choice is mineral wool, which is manufactured through an energy-intensive process.
This new substrate is called "ESOIL" and is made of cellulose (a material found in plant walls) and PEDOT (a conductive polymer).
This conductivity makes it possible to apply a small voltage to the roots of barley plants grown in the substrate. During the 15-day study, electrical stimulation caused plants to grow 50% (by dry weight) compared to control seedlings grown in soil without stimulation.
We can't say that hydroponics will solve food security, but it can certainly help.
This is not the first study to show that electrical stimulation can help plant growth. However, the Link Ping team said that previous studies had used higher voltages, and that their ESOt required a low voltage with very low energy consumption, which may have made it more practical.
Since the control group was also grown in soil without electrical stimulation, it is unclear how this method compares to barley grown in a conventional substrate. This study ended when the plants were still seedlings, so more research is needed to test the long-term effects of soil and stimuli.
Looking to the future: The next step for Swedish scientists will be to figure out how their method works so they can further optimize its application in hydroponic agriculture.
"We don't yet know how it actually works, or what biological mechanisms are involved in it," Starvrinidou said. "We found that seedlings handled nitrogen more efficiently, but it is not clear how electrical stimulation affects this process. ”