Large-fruited Tomato Production as Affected by Root-zone Extension and Wick Addition During Cultivation in a Capillary Wick System

This study was conducted to investigate the possibility to use capillary wick system in large-fruited tomato production. The first experiment in the autumn-winter season of 2006 was carried out to investigate the effects of the amount of substrate on growth and yield of tomato. Treatments involved growing large-fruited tomato in one box (2.8ℓ/plant) continuously, or adding substrate at flowering of the 7th truss in a 2nd box (5.6ℓ/plant). Fruit yield was higher when the root-zone was extended with double the substrate volume. The second experiment in spring-summer season of 2007 was aimed at improving growth and yield of tomato by extension of root-zone and addition of wick. Tomato plants were either grown in one box with one wick continuously, or with addition of substrate in a 2nd box at flowering of the 4th truss. Additionally, one more wick was inserted into 50% of the 2nd boxes. Half of the plants were grown in two boxes with one wick, and the other half with two wicks. Higher yield was obtained from the plants grown in two boxes with two wicks, suggesting that fruit yield was increased by increasing water transport through wick addition coupled with root-zone extension. Plant growth and fruit yield of large-fruited tomato was stable without blossom-end rot when root-zone was extended and half strength of Ohtsuka-A nutrient solution supplied through the capillary wick system. There was, however, a slight sign of physiological disorder at the leaf margins similar to potassium deficiency.