Abstract
1) The discharging ability of seeding machine for soybean which was on the market was studied on the opening diameter, the peripheral velocity and the pitch of seed holes, then the optimum conditions for accurate seeding were clarified.
2) According with the above results, the seeding machine with the declining large diameter cell was developed.
3) The developed seeding machine is able to have a high accuracy of seeding under the 0.7m/s working speed and a capability of speed up to 1.7 times of the machine which is on the market.
4) In the field condition, the seeding accuracy of the developed machine was investigated about the variation of the seeding interval, the seeding depth and the linearity of seeding row. The variation of them was statistically small when the clod breaking ratio was higher. But it was not clear on the working speed.
5) In order to get over 80% of the plant standing ratio, the ratio of clod breaking was required over 80% and the maximum limit of working speed was 0.9m/s under the soil condition with high clod breaking ratio.
