Recycling of drained nutrient solution in hydroponic cultivation of horticultural crops is important in the conservation of the water resources, reduction of production costs and prevention of environmental contamination. Objective of this research was to obtain the fundamental data for the development of a recirculation system of hydroponic solution in semi-forcing cultivation of ‘Bonus’ tomato. To achieve the objective, tomato plants were cultivated for 110 days and the contents of inorganic elements in plant, supplied and drained nutrient solution were analyzed when crop growth were in the flowering stage of 2nd to 8th fruiting nodes. The T-N content of the plants based on above-ground tissue were 4.1% at the flowering stage of 2nd fruiting nodes (just after transplanting), and gradually get lowered to 3.9% at the flowering stage of 8th fruiting nodes. The tissue P contents were also high in very early stage of growth and development and were maintained to similar contents in the flowering stage of 3rd to 7th fruiting nodes, but were lowed in 8th node stages. The tissue Ca, Mg and Na contents in early growth stages were lower than late growth stages and the contents showed tendencies to rise as plants grew. The concentration differences of supplied nutrient solution and drained solution in NO3-N, P, K, Ca, and Mg were not significant until 5 weeks after transplanting, but the concentration of those elements in drained solution rose gradually and maintained higher than those in supplied solution. The concentrations of B, Fe, and Na in drained solution were slightly higher in the early stages of growth and development and were significantly higher in the mid to late stages of growth than those in supplied solution. The above results would be used as a fundamental data for the correction in the inorganic element concentrations of drained solution for semi-forcing hydroponic cultivation of tomato.

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 Literature cited

• 이은모(충남농업기술원) | Eun Mo Lee (Chungcheongnam-do Agricultural Research & Extension Services)
• 박상규(충남농업기술원) | Sang Kyu Park (Chungcheongnam-do Agricultural Research & Extension Services)
• 이봉춘(충남농업기술원) | Bong Chun Lee (Chungcheongnam-do Agricultural Research & Extension Services)
• 이희철(충남농업기술원) | Hee Chul Lee (Chungcheongnam-do Agricultural Research & Extension Services)
• 김학헌(충남농업기술원) | Hak Hun Kim (Chungcheongnam-do Agricultural Research & Extension Services)
• 윤여옥(충남농업기술원) | Yeo Uk Yun (Chungcheongnam-do Agricultural Research & Extension Services)
• 박수복(㈜청오엔지니어링) | Soo Bok Park (Chung-oh Engineering Co. Ltd)
• 정선옥(충남대학교 바이오시스템기계공학과) | Sun Ok Chung (Department of Biosystems Machinery Engineering, Chungnam National Univ.)
• 최종명(충남대학교 원예학과) | Myung Choi (Department of Horticultural Sciences, Chungnam National Univ.) Corresponding author