Abstract
(1) The efficiency of soil conditioner (Aerotil) for the reformation of leaky paddy field, by planting rice in the pot shown in Fig.1,was estimated. Consequently, it was observed that the reformative effect of soil conditioner was distinguished and yield of rice correspondingly increased (table 2). (2) The durability of the effect of soil conditioners was investigated since 1952,using Aerotil Wettable Flake, A-22 and Aerotil Dry Form in pot experiments and Krilium, A-22 and CMC were used in plot expriments(1×1m), and crop-planting was repeated several times. The results were as follows : a) The amounts of water stable aggregate of soils treated with soil conditioners were more than control at 3 years after treatment. b) The efficiency of soil conditioners for the facilitation of germination was observed. But the number of seeds germinated was almost equal through all the pot at twenty days after seeding (table 2) c) Tthe effect of soil conditioner for the increase of yield of crops in the pot and plot experiments was not observed (table 3).
