Utilization of multiporous materials from baked soil as the artificial substrate for tomato [Lycopersicon esculentum] hydroponics

In order to evaluate applicability of multiporous materials (MM) made from baked soil as the artificial substrate for hydroponics, we investigated the characteristics of MM and tomato cultivation using MM. 1) specific gravity and water holding rate with the 2 mm MM diameter was bigger than that of 5 mm. But, hardness about the 5 mm MM diameter was greater than that of 2 mm. Specific gravity and hardness in MM made of baking soil with waste fibers (MMf), was less than with no fiber (MMnf), but water holding rate in MMf was bigger than that of MMnf. 2) MM has a tendency to increase calcium, magnesium, iron and manganese contents and to decrease potassium content sin nutrient solution, compared with the rockwool. But, there were no effect on the tomato growth. 3) for tomato with a smaller stem diameter in the 5th-7th truss, less amount of irrigation can be found. When there was more amount of irrigation, the total tomato fruits gained more weight. Compared with the 5 mm MM diameter, the 2 mm MM diameter fruits was lighter in weight. The weight of the tomato which was made from MMnf was smaller than that of MMf. When there was less irrigation, the marketable fruits are lighter, further tomato fruits with the 5 mm MM diameter were lighter than those of 2 mm in weight. 4) It has been proved that the brix of the tomato with the 5 mm MM diameter at the 6th-7th truss was greater than that of 2 mm by 7-8%. 5) Total weight of the tomato fruits of the 5 mm MMf diameter, was lighter that of rockwool. However, marketable fruits, the rate of efficiency in MMf was higher and heavier than that of rockwool. There was little difference in brix between the tomato fruits using MMf and rockwool. 6) In terms of the total weight of the tomato fruits, the used MMf with the heating was the heaviest. The use MMf with the non-heating was second, and the smallest was the new MMf