Feature

Cool tech for sustainable farming

George Annor

What if the next revolution in sustainable farming could be sparked by just air and electricity?

At the University of Minnesota Twin Cities, Professor George Annor is leading research into cold plasma technology — a novel approach that has the potential to help farmers confront rising costs, reduce the need for synthetic fertilizer, naturally manage pests and significantly increase crop yields.

Produced by applying electrical energy to a gas, cold plasma may offer a variety of benefits to agriculture. These potential benefits are already being demonstrated in the lab: cold plasma can increase soybean germination rates by 30%, as shown in research collaborations with Cornell University and the University of California Davis.

“By using cold plasma to clean the surfaces of the seeds, you increase what we call the ‘wettability’ of the surface, which means that the surface readily accepts water,” says Annor, a McKnight Presidential Fellow who holds the General Mills Endowed Professorship in Cereal Chemistry and Technology in the University of Minnesota’s College of Food, Agricultural and Natural Resource Sciences. “That speeds up the penetration of water into the seed — and if the seed senses water, it will initiate germination.”

A whole crop of benefits

Using cold plasma technology for seed germination is only the beginning when it comes to its potential agricultural applications. Plasma-activated water has a variety of practical uses for farmers.

Created by exposing ambient air to electricity and then “bubbling” the resulting plasma into water, plasma-activated water is temporarily enriched with reactive compounds like nitrates and nitrites.  

“What we are basically doing is making our own fertilizer by simply using water and electricity,” says Annor. “The plasma actually pulls nitrogen from the air, breaks it down and mixes it with the water to form plasma-activated water with high levels of nitrates and nitrites — very important nutrients for plants.”  

In addition to reducing the need for fertilizer inputs, plasma-activated water has natural disinfecting and pest-control properties.

“Our colleagues at UC Davis have been able to prove that when you treat plants with plasma-activated water, it prevents the multiplication of spider mites,” says Annor. “It actually helps build the defenses of the plant.”  

Going from lab to field

There are some barriers when it comes to implementing cold plasma technology, Annor says. Although it holds great promise for helping farmers save money while maximizing output (due to greater yields, less need for fertilizer and pesticides, etc.), there are startup costs associated with implementing the technology.

In addition, a recent survey conducted by Annor’s team showed that the majority of farmers consulted weren’t familiar with the technology, so raising awareness will be crucial.

Despite these challenges, Annor and his colleagues believe in the potential of cold plasma technology to transform agricultural practices, and they continue to explore new applications. 

Their current research is focused on the harvested crop itself — for example, whether tomatoes grown using the technology have a higher nutritional value, a longer shelf life or a better flavor profile than conventionally grown crops.

“Using plasma-activated water could result in significant savings to farmers and significant increases in yields,” Annor says. “Now what we need to do is partner with farmers and help them test it in their fields.”

You can make a gift to support sustainability efforts through the University of Minnesota Sustainable Agriculture Fund.