Ken Kawasaki

Improvement of Soybean Emergence on the Barley Harvested Upland Field Converted from Paddy Field

The tractor mounted straw mulching rotary seeder and the no-till seeder equipped in front of a riding-type rice transplanter for soybeans were developed in order to improve the emergence on the converted paddy fields under various weather and field conditions.1. By using shallow cultivating rotary tiller which forms uncultivated ridge under tilled surface soil, the risk of seed submergence were evaded even in the heavy rainfall. The emergence percentage was improved by means of mulching chopped straw. In addition, the mulch suppressed weed markedly and avoided the drought stress or crust making of the surface soil.2. The no-till seeder which was developed to perform seeding under wet field conditions during suitable sowing period. The emergence percentage decreased with increasing soil moisture content but the value attained about 70% around maximum water holding capacity. This no-till seeding method was adaptable to the wet field conditions.