2009 Volume 78 Issue 2 Pages 242-249
Heat production and germination of rice seeds kept in a hopper and vat under oxidizing conditions were examined. In addition, seedling emergence and establishment from these seeds directly seeded with an air-assist row seeder were examined in the field. Under the crowded conditions in the hopper, the seeds coated with reduced iron (sealed) were rapidly heated and showed a reduced germination rate. In contrast, the seeds coated with iron oxide (sealed) showed gradual increase in heat production and gradual decrease in germination rate. The germination rate after seeding (after accumulation) was highest in the seeds coated with iron oxide (sealed) following by those coated with reduced iron (sealed), and reduced iron (oxidized without sealing). This order was reflected in the seedling establishment rate and the dry-weight increase of the plants. Our results indicate that the effects of excessive heating may be avoided by using iron oxide-coated seeds, and that machine sowing may be used in a large scale compartmentalization system to promote seedling emergence and establishment.
