Combined action of gamma radiation and exposure to copper ions on Lemna minor L

Abstract

Purpose

Under natural conditions, the reaction of living organisms to the action of acute gamma radiation depends on other stressors, including heavy metals. The aim of this work was to study changes in morphometric parameters, the content of photoassimilation pigments and the level of oxidative stress in irradiated duckweed at various copper concentrations in the culture medium.

Materials and methods

As a model organism, we used Lemna minor L. Duckweed was exposed to acute γ-radiation at doses of 18, 42, 63 Gy. After irradiation, the plants were transferred into a medium containing 3, 5, 6.3 μmol/L Cu. On the 4th day of exposure, the levels of chlorophyll, carotenoids, malondialdehyde (MDA) were measured; after 7 days, the specific growth rate, the level of damage, the change in the frond area, copper concentration in plant tissues were determined.

Results

The action of γ-radiation (18, 42, 63 Gy) and copper ions (3, 5, 6.3 μmol/L) reduced the growth rate, increased the membrane lipid peroxidation, reduced the area of the fronds more significantly than under the separate action of the factors. The factors acted antagonistically on the specific growth rate. The content of copper in the tissues of irradiated plants (42, 63 Gy) increased.

Conclusion

Irradiation of duckweed with acute doses of gamma radiation reduced the resistance of plants to excess copper in the environment.

Keywords:

• Gamma radiation
• copper
• oxidative stress
• Lemna minor L.

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Notes on contributors

Irina S. Bodnar

Irina S. Bodnar, PhD, is a Researcher at the Department of Radioecology, Institute of Biology of Komi Science Center of the Ural Branch of the Russian Academy of Sciences, Syktyvkar, Russia.

Evgenia V. Cheban

Evgenia V. Cheban is laboratory assistant at the Department of Radioecology, Institute of Biology of Komi Science Center of the Ural Branch of the Russian Academy of Sciences, Syktyvkar, Russia.