Abstract: The present invention provides an apparatus for producing water having redox activity. In the apparatus, at least one of oxygen, ozone, chlorine, nitrogen monoxide, and ammonia as a reaction precursor is previously mixed into water or running water while regulating the concentration of the dissolved substance followed by the application of ultrasonic vibrations, whereby active oxygen species are generated in water. In another embodiment, water or running water is brought into contact with a catalyst to which ultrasonic vibrations or electromagnetic waves have been applied, whereby active oxygen species are generated in water.

Abstract: Disclosed is a method of preventing diseases in plants which can bring about a redox reaction in the inside of plant cells thus inducing the expression of pathogen-resistance genes in the plant cells. There is no possibility that residual contents remain in soils. It is also possible to cultivate plants which are strong against diseases. By bringing water which contains reactive oxygen species and allows the reactive oxygen species to be held and to function for a long period into contact with plants, the expression of the pathogen-resistance genes which the plants possess is induced. Accordingly, the water containing reactive oxygen is absorbed into the plants to prevent diseases in plants.

Abstract: The present invention provides an apparatus for producing water having redox activity. In the apparatus, at least one of oxygen, ozone, chlorine, nitrogen monoxide, and ammonia as a reaction precursor is previously mixed into water or running water while regulating the concentration of the dissolved substance followed by the application of ultrasonic vibrations, whereby active oxygen species are generated in water. In another embodiment, water or running water is brought into contact with a catalyst to which ultrasonic vibrations or electromagnetic waves have been applied, whereby active oxygen species are generated in water.