Spraying Ozonated Water under Well-Ventilated Conditions Does Not Cause Any Visible Injury to Fruit-Vegetable Seedlings

Abstract

To determine whether horticultural plants are visibly injured by being sprayed with ozonated water (OW) for airborne-disease control, we sprayed OW with a dissolved ozone concentration (DOC) of 4.0 or 8.0 mg L−1 or distilled water (DW) on melon (Cucumis melo L. ‘Andes’), tomato (Lycopersicon esculentum M. ‘Momotaro-York’), watermelon (Citrullus lanatus M. ‘Fujikou’), cucumber (Cucumis sativus L. ‘Sharp’), green pepper (Capsicum annuum L. ‘Kyounami’), and eggplant (Solanum melongena L. ‘Senryo-nigou’) seedlings under well-ventilated conditions. The OW and DW were sprayed on the seedlings at 10 a.m. and 2 p.m. on 3 successive days. No yellowing, chlorosis, necrosis, or malformation was observed for any of the seedlings during this period and also 1 day after the last OW spraying. These results indicate that intensive spraying of OW with a high DOC, for airborne-disease control, does not cause any visible injury to the fruit-vegetable seedlings used as long as the spraying is carried out under well-ventilated conditions.