An ozonization system (Ozomax OZO 6VTT, IGT limited, Ontario, Canada) was installed in a commercial plastic-covered greenhouse in Danville, Quebec, Canada (www.savoura.com) to study the effects of the disinfection and recirculation of the nutrient solution in a tomato crop. The ozonization system was compared to a conventional growing system where the nutrient solution was not treated, neither ...