Algae. 1996; 11(1): 155-159.

Effect of Ultraviolet-B Radiation on Ulva pertusa Kjellman (Chlorophyta). I. Growth and pigment Content

Taejun Han

Department of Biology, University of Inchon

Discs cut from thallus of the intertidal alga, Ulva pertusa were exposed in the laboratory to UV-B radiation of similar irradiance to the ambient levels (2.0 Wm super(-2)) measured on a clear day in September, 1995. The fresh weight, surface area and cell area were unaffected by the various durations of UV exposure whereas the total chlorophyll content was significantly reduced by approximately 50% after only 2 h irradiation. Chlorophyll destruction by UV-B is likely to be a function of a cumulative dose. The UV-absorbing pigment contents fell proportionally with the total chlorophylls. UV-irradiated thalli showed a 10% higher transmittance in the 280-400 nm waveband range than nonirradiated thalii, suggesting that some of the cellular components might have been disturbed in the former.

Keywords : chlorophyll, UV-absorbing pigments, UV-B, Ulva pertusa