Scientific view: Which bacteria could reduce greenhouse gas emissions in agriculture

Scientists at the Norwegian University of Life Sciences and the Institute for Applied Systems Analysis in Austria have discovered a method to reduce N2O emissions. The scientists foundbacteria that can break down nitrous oxide as it forms in the soil, preventing the gas from escaping into the atmosphere. Researchers believe that this method alone could reduce agricultural nitrous oxide emissions by a third.

Plants require a lot of nitrogen to grow, so productive agriculture requires nitrogen fertilizers. Nitrogen deficiency in the soil was a serious problem for agriculture until agricultural chemist Fritz Haber developed a technology for industrially producing nitrogen fertilizers from atmospheric nitrogen. Thanks to this technology, food production in the world has not lagged behind the rate of population growth for 120 years.

However, there are microorganisms in the soil that produce the greenhouse gas N2O, and fertilizers stimulate its production.

Nitrous oxide emissions are known to be regulated primarily by soil bacteria, making efforts to reduce them difficult due to their elusive nature. Scientists have been conducting fundamental research into how microorganisms convert nitrogen in soil for over 20 years. During this time, they have carefully studied what happens when microorganisms do not have access to sufficient oxygen, i.e., are in a state of hypoxia.

During heavy rainfall and fertilization, some areas of the soil become hypoxic. Since microorganisms do not have access to oxygen, they are forced to find other ways to obtain energy. Many of them can use nitrate instead of oxygen, and in a process called denitrification, microorganisms convert nitrate into other gases. One of these is nitrous oxide, and in this way, microorganisms contribute to greenhouse gas emissions.

The solution to reducing N2O emissions is to use a special type of bacteria that cannot produce nitrous oxide, but can reduce it to harmless nitrogen gas (N2).

 Finding the right bacteria was not easy. It had to grow quickly on organic waste, function well in soil, and have a long lifespan to reduce N2O emissions during the plant's growing season.

Research is currently ongoing to find different types of nitrous oxide-consuming bacteria, testing them on different types of organic waste used as fertilizers in different climate zones. It is necessary to find a wide range of bacteria that can function in different types of soil and with different fertilizer mixtures.

Effective nature management and preservation of the ecosystem as a whole are important tasks. The All-Russian Plant Quarantine Center (FGBU "VNIIKR"), as a scientific center of ROSSELKHOZNADZOR , as part of the implementation of research work, is actively involved in the processes of finding solutions that, through a built system of quarantine phytosanitary safety, allow finding answers to a wide range of questions.

Elena Karimova,
PhD in Biology