USING ULTRAVIOLET-C LIGHT AS A PLANT GROWTH REGULATOR^©

Plants use sunlight for photosynthesis and are exposed to the ultraviolet (UV) radiation that is present in sunlight. Ultraviolet radiation is divided into three classes: UV-C, UV-B, and UV-A. The ultraviolet-C (UV-C) region of the UV spectrum includes wavelengths from 200-280 nm; these highly energetic wavelengths are absorbed by ozone and are not present in the sunlight at the earth’s surface. Under normal growing conditions, effects of UV-C light are not seen on plants.