Growth characteristics of two bloom-forming synurophytes (Mallomonas elongata and Synura petersenii) at different nitrate and phosphate concentrations

Two dominant planktonic bloom-forming algal species in a small shallow eutrophic pond were identified as Mallomonas elongata and Synura petersenii by electron microscopy. Their growth requirements were investigated as uni-algal cultures in a laboratory study. The maximum population growth and maximum growth rate of M. elongata occurred at concentrations of 24 μM nitrate (NO ₃) and 5 μM phosphate (PO ₄) at a temperature of 15°C and a pH of 6. Synura petersenii grew maximally and exhibited the highest growth rate at a NO ₃ concentration of 24 μM and a PO ₄ concentration of 2 μM. Mallomonas elongata and S. petersenii had similar nutrient requirements for optimum growth, suggesting that the biomass of these two species can be controlled by nutrient gradients.