Impacts of Different Phosphorus Contents on the Growth of <i>Cylindrospermopsis raciborskii</i> in the Aquatic Environment

Abstract

Background: Cyanobacteria are the most important group of algae. Many factors are involved in the rapid growth of algae such as phosphorus and nitrogen contents. Objectives: The current study aimed at evaluating the effect different phosphorus concentrations on the growth rate of Cylindrospermopsis raciborskii during the aquatic life. Methods: The experiment was carried out for 12 days at three phosphorus concentrations and one control group in Zehnder 8 and Blue-Green 11 media. The rates of cell division per day (G) and specific growth rate (µ) were separately estimated for each group. Cyanobacterium was tested at three phosphorus concentrations; 150, 300, and 600 µg/L. Results: The current study results showed that increasing phosphorus concentration had a significant effect on the growth of C. raciborskii in some particular days of cultivation. The maximum growth rate (0.9 per day) was observed at 7 g/L phosphorus concentration. Conclusions: Phosphorus was a limiting factor and contributed to the removal of toxins from the alga and its blooming. The maximum growth rate was observed in the group treated on the day 8 of cultivation with phosphorus concentration of 300 µg/L.