THIS CONTENT IS BROUGHT TO YOU BY the Norwegian University of Life Sciences (NMBU) - read more
This plant doesn't tolerate radiation very well
Plants differ greatly in how they respond to radiation and in their ability to detect and repair damage.
April 2026 marked the 40th anniversary of the Chornobyl nuclear power plant disaster. This event led to the spread of a radioactive plume across Europe and beyond. Its impact is still felt today.
Besides the danger to human and animal health, contamination of forest ecosystems is a major consequence of such nuclear accidents. This includes the entire forest – trees, soil, water, animals, plants, and microorganisms.
Radioactive contamination from the disaster is still present in the environment today. The Chornobyl accident remains the largest source of radioactive contamination on land and in freshwater in Norway.
Why do some plants cope better with radiation?
When exposed to radioactive contamination, different plant species show different levels of sensitivity. Some can tolerate high radiation with little consequence. Others are more sensitive and are damaged even at lower contamination levels.
Researchers at the Norwegian University of Life Sciences (NMBU) have now compared Norway spruce with thale cress. Norway spruce is a radiation-sensitive species. Thale cress (Arabidopsis thaliana) is a small, well-studied plant that is more radiation-tolerant.
By exposing both plant species to the same radiation levels, they gained key insight into why their sensitivity differs.
Testing plant responses across radiation levels
The researchers exposed seedlings from each species to different levels of gamma radiation for 48 hours. They started with relatively low levels, up to levels found in contaminated environments. Even the lowest levels used in the experiment were far higher than what normally occurs in nature.
Payel Bhattacharjee explains that Norway spruce suffered damage to its DNA and other parts of its cells even at the lowest radiation levels.
“Norway spruce showed reduced growth at the highest radiation intensity,” she says.
Thale cress, on the other hand, continued to grow normally. It had less DNA damage, and its cells were damaged only at the highest radiation levels. This means that the cellular machinery responsible for repairing radiation-induced damage responds quickly and is highly sensitive.
“We found that Arabidopsis can rapidly activate internal 'emergency' systems, even at low radiation levels. These trigger protective responses and DNA damage repair,” says Bhattacharjee.
In short, the alarm bell rings and the radiation damage is fixed quickly and effectively.
Norway spruce was not so reactive. This species showed similar protective mechanisms as thale cress, but only at much higher radiation doses. The spruce was less effective at repairing the damage.
Implications for contaminated ecosystems
Professor Jorunn E. Olsen leads the research group studying radiation sensitivity in plants. According to her, this research is important for risk assessment and for protecting plant communities in areas contaminated by radiation. When radiation levels are high, sensitive species such as Norway spruce need special measures to limit critical damage.
“The molecular insights we gained may support future efforts to identify plants that are better able to cope with radiation in vulnerable environments,” she says.
The findings may also be used to develop plants that are more resistant to other types of environmental radiation.
“This includes exposure to elevated UV‑B in some regions, which is becoming more important as climate conditions change,” says Olsen.
Reference:
Bhattacharjee et al. High radiosensitivity in the conifer Norway spruce (Picea abies) due to less comprehensive mobilisation of protection and repair responses compared to the radiotolerant Arabidopsis thaliana, Plant Stress, 2025. DOI: 10.1016/j.stress.2025.101010
More content from NMBU:
-
The water temperature salmon experience as embryos can shape their future health
-
Green school surroundings matter most in these neighbourhoods
-
How Kilimanjaro changed the lives of Norwegians with substance use problems
-
Chornobyl 40 years later: What we learned and what we forgot
-
Shopping centres contribute to better health and quality of life
-
We're eating more cashew nuts – and the consequences are serious
