The main effect is on the photosynthetic apparatus - the pigments and enzymes that absorb light and use its energy to process CO 2 into sugar. Tests have shown that plants vary in their sensitivity to UV-B. Most species tested so far have been crops. In experiments subjecting rice plants to a 33 per cent increase in UV, the plants were visibly damaged and the yield of rice-grain fell by 20 per cent. However, a 20 per cent increase is a possibility.
Some rice varieties are more resistant to UV than others.
Just as different races of humans can produce different quantities of protective melanin, so plants differ. In the sea, phytoplankton are also at risk. External sites are not endorsed by the Australian Academy of Science. The Australian Foundation for Science and the Science and Technology Awareness Program of the Commonwealth Department of Industry, Science and Resources are also supporters of Nova . This topic is sponsored by the Commonwealth Department of Industry, Science and Resources .