Discussion
The toxicity of M. aeruginosa is known to change depending on
seasons (Ferrao-Filhoetal.2000). The cyanobacterial strain we
used here is nothighly toxic because none of the test species died
within 48h,even when raised on 100% Microcystis diet (Lampert
1987). Yet, it was sufficiently toxic to reduce the growth rates of
both rotifer species (we did not quantify the concentration of
microcystin,the main toxic componentin M. aeruginosa).