Studies on the Non-Tillage System of Rice Production(I). On the hardness of soil and the efficiency of non-tillage transplanting machine.

In this study, changes in the hardness of soil in paddy fields over time and working efficiencies of rice transplanting using the non-tillage transplanting machine were investigated.The main results obtained were as follows:1) The hardness of soil after irrigation were gradually softened over time, but the hardness of soil in some fields did not get soft so quickly as others. So, irrigation for the nontillage transplanting field should be done before the tenth day of transplanting time.2) The efficiency of the non-tillage transplanting machine were much affected by the hardness of soil. The rate of seedling floating and the rate of miss planting of seedlings increased in the harder soil field more than 0.70MPa. The machine showed good run and less slippage rate in the non-tillage field.