Growth Inhibition on Gametophytes of Laminaria religiosa Induced by UV-B Irradiation

抄録

Laminaria religiosa spores that settled on glass slides were irradiated with UV light with various qualities and then were incubated at 10°C at 10L:14D. The wet weight of young sporophytes in a unit area of each glass slide was measured two months after UV irradiation. The results obtained showed that gametophyte growth was strongly inhibited by irradiation with UV-B (320-280 nm). The inhibition rates were approximately 50, 70 and 90% for 0.5, 1 and 3 kJ/m² of the damaging-UV, respectively. These results indicate that the reproduction of L. religiosa in shallow waters might be inhibited by sun light since the maximum of the mean value of the daily amount of damaging-UV in July 1994 in Sapporo was reported to be 0.7 kJ/m².