Optimization of Paramecium tetraurelia growth kinetics and its sensitivity to combined effects of azoxystrobin and cyproconazole

For using an organism for ecotoxicological studies, it is important to understand its model of growth under some physicochemical parameters that influence with a direct manner its development. The knowledge of the optimal parameters for the paramecia development leads to realize a model of growth with clear stages. For that, we tried to study the influence of temperature, pH, nutrient density in the culture medium and pollution on the growth ofParamecium tetraurelia. Obtained results showed that paramecia prefer definite conditions. However, the growth was better in temperatures included between 25 and 30°C, with preference to increased temperatures and a slightly acidic pH. The culture medium wasprepared from the mixture of several vegetables which the rates were studied depending to the growth. The combined effects of azoxystrobin and cyproconazole on the growth kinetics were studied. Results showed that treatment affected the population growth, the generation time and the velocity of generation.   Key words: Paramecium tetraurelia, growth kinetics, physicochemical parameters, azoxystrobin, cyproconazole.