Potential Productivity of Hydroponically - grown Tomatoes ill the Genting Highlands , Malaysia

Five trials were carried out to assess the potential productivity of tomatoes in a deep culture hydroponic system in Genting Highlands (1,200 m a.s.l.), Malaysia. The tomatoes were maintained as single-stemmed plants using the layering and vertical methods ofplant training. Determinate and indeterminate varieties producing large, medium and small-sized fruits were investigated in these trials. Under the layering system, the indeterminate plants could last for nine months but if crops were kept for only six months, two crops per year could be produced with a potential yield of 252-288 ton/ha/year. The vertical system could produce three crops per year with a range of 21 0-248 tonnes/ha/year for the three sizes offruits. The determinate varieties produced a wide range of yields and, with three crops per year, a yield range of 131-216 ton/hal could be expected. The yields obtained in the tested hydroponic system were at least five to ten times higher than those obtained from traditional soil cultivation under highland and lowland conditions in Malaysia. INTRODUCTION Tomatoes (Lycopersicon esculentum Mill), an important vegetable crop in Malaysia, is traditionally grown in soil, in the Cameron Highlands (1,000 to 1,500 meters above sea level). Tomato cultivation using hydroponics or soilless culture techniques, widely practised in Europe, have not gained acceptance by local commercial growers. One of the reasons for this is the high initial capital costs and the fear of not achieving sufficient productivity to off-set the high initial capital outlay. There is thus the need to assess the potential productivity of tomatoes under a hydroponic system and to monitor potential problems that may affect the productivity of the crop. The following is a report on some trials carried out to determine the potential productivity of tomato, as a crop, in a hydroponic system (Kyowa Hyponica) using a number of