The concentrated deep seawater has been discharged abundantly in the processes manufacturing many kinds of goods from the deep seawater. In this study, a suitable application of the concentrated deep seawater for the high quality tomato production was examined by analyzing effects of the short-term salt stress treatment with the concentrated deep seawater on plant physiological functions and fruit quality with special reference to osmotic adjustment, antioxidation and sensory properties of fruits. Tomato plants (Lycopersicon esculentum Mill.) with four fruit trusses were grown in the NFT system with the intermittent applications of the short-term salt stress and the continuous application of the long-term salt stress, where the concentrated deep seawater was applied to the standard nutrient solution. The short-term (one week) salt stress was applied three times to the respective fruit trusses of 1st to 4th at one-week intervals. This intermittent salt stress treatment to each fruit truss significantly affected osmotic adjustment and antioxidation in tomato plants and brought the value-added high quality tomatoes enriched in sugar, minerals, antioxidants and flavor etc. Furthermore, the intermittent applications of the short-term salt stress showed the possibility to improve the extreme depression of fruit growth, the higher incidence of blossom-end rot and the depression in plant vigor which were caused by the continuous long-term salt stress treatment. In this study, a new methodology to produce value-added vegetables was demonstrated by applying the natural resource, the environmental stress and plant adaptive functions.
