ISSN:
1432-184X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract In the absence of inhibitory concentrations of copper, the photoautotrophic growth of Chlorella vulgaris INETI58C at 27°C exhibited a higher specific growth rate and reached a higher maximal concentration of biomass, under irradiance of 150 W m−2, compared with 100 W m−2. However, when the mineral growth medium was supplemented with CuSO4 (range 40–80 μM), algal growth was significantly affected at the higher light intensity. In the presence of Cu2+, the increase in dry biomass was uncoupled from the increase in cell concentration since more than 16 autospores gathered together, inside the enlarged mother cell, suggesting that copper arrested the normal bursting of the mother cell wall. At the higher irradiance, growth medium supplementation with 80 μM of CuSO4 led to bleaching of photosynthetic pigments. No growth was observed, while, under the lower irradiance, growth was only slightly inhibited. Results clearly showed that copper toxicity to growth of C. vulgaris was strongly influenced by light intensity. Higher light intensity elicits lethal or sublethal Cu2+ damage at concentrations lower than the threshold level for damage at lower light intensities. Cu2+ may elicit lethal or sublethal light damage at irradiances lower than the threshold level for unpolluted aquatic systems.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002489900074
