PHOTOSYNTHETIC PERFORMANCE OF HEALTHY AND VIRUS-INFECTED FELDMANNIA-IRREGULARIS AND F-SIMPLEX (PHAEOPHYCEAE)

The filamentous brown algae Feldmannia simpler and F. irregularis are attacked by aquatic viruses, which propagate in deformed sporangia of the host plants. In order to evaluate a possible detrimental effect of the pathogen, photosynthesis-irradiance response curves and pigment concentrations of healthy and infected plants were compared. Photosynthetic performance of infected plants was significantly reduced and associated with a decrease in chlorophyll a and c content. In Feldmannia irregularis, which had a relatively low photosynthetic capacity, the virus infection produced a more severe effect than in F. simpler.