Double trouble for plants

Depletion of the ozone layer and a toxic heavy metal are combining to cause irreparable damage to plants.

The research is reported in the latest edition of the Royal Society of Chemistry Journal Photochemical and Photobiological Sciences.

Dr Javier Martinez-Abaigar and a team from the Universidad de la Roca, Spain, have shown that a plant's ability to repair DNA damage caused by the sun's UV-B radiation is impaired by the metal cadmium.

Repair of such DNA damage is essential for plants to survive.

The researchers investigated the response of the aquatic plant liverwort to the individual and combined effects of cadmium and UV-B radiation.

While Cadmium alone had only a modest effect on DNA -and UV-B caused some damage by itself - the highest levels of damage were caused by the two combined.

Cadmium - most well known for its use in batteries - is released into the environment through waste incineration, power stations, vehicle exhausts and leaching from fertilisers. It is also released through natural weathering of minerals.

Plants take up Cadmium from the soil as they draw in water as part of their natural growth and maintenance cycle. The metal then accumulates in the plant's tissues.
 
In the last quarter of a century, the ozone layer has been significantly depleted, exposing plants (and other life) to more UV-B radiation.

Dr Martinez-Abaigar said: "Such studies will become increasingly important with the ozone layer at risk of further depletion in the future."

with thanks to Elinor Richards for the original article.