Study on Improving the Emergence of Direct Sowing Sugar Beets (Part 2)

The Soil Compaction to Middle-layer for Increasing Emergence

Abstract

In the part 1 of this study, 60% of less than 4.75mm diameter clod size and high compressing force of the press roller attached to the seeder are required to achieve an 85% emergence rate. This study describes that the emergence rate can be increased to 85% by increasing the compaction of the middle-layer soil prior to rotary harrowing and by adding 10-kg weight on the press roller. The middle-layer soil compaction increases both the cone index of soil at a depth of 5-20cm, and the liquid-phase rate of soil at a depth of 1-11cm. The emergence rate obtained using this method was better than that obtained by conventional tillage. Although rotary harrowing damaged the capillary phenomenon between the middle and the seed layer, the high cone index achieved by middle-layer soil compaction and the soil reconsolidation achieved by the press roller were considered to replicate the phenomenon.