Stable Strontium Distribution and Effects on Plants

Strontium (Sr) is a wide-spread alkaline earth metal that is similar to calcium (Ca) in its chemical properties, although it does not play the physiological role inherent to the latter. At low doses, Sr can stimulate plant growth and development. However, at elevated levels in the environment, it has a negative effect on many processes occurring in plant cells, leading to growth inhibition and reduced productivity. The majority of studies have been focused on the effects of radioactive Sr isotopes which produce additional toxic effects due to ionizing radiation, but the effects of stable Sr have not received enough attention. The current scoping review summarizes the data on the uptake mechanisms and transport pathways of stable Sr and examines the characteristic patterns of its distribution in plant tissues and organs. Available data on the effects of stable Sr on enzyme activity, mineral nutrition, photosynthesis, plant growth, and morphogenesis are analyzed. Understanding the transport pathways of Sr, as well as the factors determining its dual effects on plant growth and development, underlies the development of approaches used in biofortification and phytoremediation technologies. The review may be useful for researchers working on plant mineral nutrition, metal stress, and phytoremediation.