The bacterium Pseudomonas syringae causes freezing of supercooled water at temperatures close to 0 degrees C. In this study, the growth kinetics and ice nucleation activity (INA) of the bacterium P. syringae pv. syringae cit 7 were investigated in a batch and continuously operated laboratory scale bioreactor system. Under continuous culture conditions, the bacterial INA decreased with an increase in dilution rate. The maximum biomass and INA productivities were obtained at a dilution rate of 0.054 h(-1) at 25 degrees C and pH 7.0. The results of this investigation can be applied towards the large scale production of P, syringae bacteria for snow making and other commercial applications of ice nucleation.