| Autor: |
Donat-P. Häder, Heike Herrmann, H.K. Seidlitz, F. Ghetti, M. Köfferlein |
| Rok vydání: |
1996 |
| Předmět: |
|
| Zdroj: |
Journal of Photochemistry and Photobiology B: Biology. 34:21-28 |
| ISSN: |
1011-1344 |
| DOI: |
10.1016/1011-1344(95)07245-4 |
| Popis: |
A sunlight simulator was used to investigate the effects of short term irradiation on photosynthetic oxygen production and chlorophyll fluorescence in the unicellular algae Dunaliella salina and Ochromonas danica . Oxygen evolution was measured with a Clark-type electrode and initial ( F 0 ) and maximal ( F m ) fluorescence were determined by means of a pulse amplitude-modulated (PAM) fluorometer. Using different long-pass filters, a UV exclusion study was performed comparing the effects of irradiation with full sun simulator light, with sun simulator light without UV-B and short wavelength UV-A radiation and without any UV component. In D. salina , exposure to full sun simulator light caused a marked drop in photochemical efficiency indicated by a decline in the initial slope of the irradiance-response curve for photosynthetic oxygen production and by a decrease in the ratio F v / F m , whereas only a slight inhibition of photosynthetic activity was observed irradiating with PAR and UV-A radiation or with PAR alone. In the case of O. danica , a strong inhibition was observed under all irradiation conditions. The results are consistent with preliminary data obtained with outdoor experiments. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect