ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
The photosynthetic light saturation curve in duckweed was lowered by 20–25% after ozone exposure (300 nmol mol−1, 1 h). The light flux and oxygen concentration during ozone-exposure had no effect on reduction of net photosynthesis. Net photosynthesis and photorespiration were both depressed by about 40% after exposure for 1 h to 360 nmol mol−1 ozone. We could not find any change in dark respiration after ozone exposure below 300 nmol mol−1. When the concentration of ozone was doubled from 150 nmol mol−1 to 300 nmol mol−1, the uptake of ozone in duckweed changed from 100 nmol m−2 s−1 to 170 nmol m−2 s−1. We found no differences in fluorescence (pattern) between ozone treated plants and the control plants during a period of 150 min after ozone treatment, but there was an increase in synthesis of the Dl-protein and a significant reduction in degradation after ozone treatment (300 nmol mol−1, 1 h). These results, together with fluorescence measurements, indicate that photochemical electron transport was not responsible for the ozone-induced reduction in net photosynthesis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1993.tb01728.x
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