Belgian researchers boost sustainable agriculture

agriculture fertilising fertiliser fertilizer
Photo: Franz W./Pixabay

Drastically reducing greenhouse gasses by 2030 and structurally lowering the use of nitrogen in agriculture poses significant challenges.

Researchers from the VIB-UGent Center for Plant Systems Biology in Belgium have presented research results that show the possibility of lower nitrogen usage by targeting microorganisms in the soil. The findings have been published in various scientific journals.

Nitrogen and the soil microbiome

Plants need nitrogen in the soil to grow. However, these plants compete with certain bacteria and archaea, two types of microorganisms that are also able to use nitrogen in the soil. These microorganisms convert nitrogen – in the form of ammonia – into nitrites and nitrates through a process called nitrification.

These nitrites and nitrates leach into the soil, groundwater, and recreational water, making them unusable for agricultural crops and negatively impacting biodiversity and water quality. Additionally, nitrates can be converted into the potent greenhouse gas nitrous oxide or laughing gas. Farmers often fertilize excessively to ensure their crops have enough nitrogen, with negative consequences for biodiversity and the environment.

Stopping nitrification

Finding substances that block nitrification by microorganisms (known as nitrification inhibitors) is the key to a more efficient use of nitrogen in agriculture. When these microscopic soil organisms consume less nitrogen, more is available for plants, reducing the need for fertilization. Previous research focused primarily on soil bacteria, neglecting archaea. Now, the Belgian researchers have explained how the mysterious microorganisms complete the picture.

“The importance of these archaea for nitrogen consumption in the soil was long ignored. Current commercial inhibitors against bacteria are not only limited, they are also ineffective against archaea. To increase the efficiency of nitrification inhibition, we looked for nitrification inhibitors against archaea,” said Fabian Beeckman, postdoctoral researcher at the Beeckman lab (VIB-UGent).

The research group developed two test methods to identify nitrification inhibitors in archaea and examined nearly 50,000 molecules for their functional use.

“Not only have we described nitrification inhibitors for archaea, but we have also shown that a combination of inhibitors against bacteria and archaea yields the best results,” said Hans Motte, project coordinator.

“We now have the tools to find and combine the best inhibitors, truly reducing nitrogen usage in agriculture.”

A sustainable future

Efficient nitrogen management is a goal that falls under the European climate law and European Nitrate Directive.

“Currently, all nitrification inhibitors are synthetic molecules,” said Tom Beeckman, group leader of the Beeckman lab.

“With our new test methods, we can now search for natural molecules that can also serve as nitrification inhibitors. In the next step, we can even look at plants that produce and excrete these products themselves in the soil. This opens the door to more efficient organic farming and sustainable agricultural systems.”

Jim Cornall is editor of Future Food Today and publisher at Ayr Coastal Media. He is an award-winning writer, editor, photographer, broadcaster, designer and author. Contact Jim here.