Effects of drying and temperature during storage of rice seeds coated withan oxygen supplier on the seedling emergence

In submerged direct-seeding rice (OryZa sativa L.) cultivation, it is impor tant to stabilize the emergence of seedlings. We examined the effects of dr ying and temperature during storage of rice seeds coated with an oxygen sup plier on the seedling emergence. The seedling emergence rate was not affect ed by the storage at 10 degreesC for 3 days. However, the emergence of seed lings was stimulated by 3-day storage at 15-30 degreesC, and the stimulatio n was especially clear at 20 and 25 degreesC. In tile seeds which were not dried or excessively dried after the seed coating, the stimulation of seedl ing emergence in spite of a 3-day storage at 20 or 25 degreesC was less evi dent than in the seeds which were dried to lose 2 to 5% weight after coatin g. The stimulatory effect of the 3 -day storage at 20-25 degreesC was obser ved in all rice cultivars examined irrespective of the method of water mana gement after seeding. Since this stimulatory effect was not reduced by a su bsequent 7-day storage at 10 degreesC, the seeds with high emergence were c onsidered to have retained the high emergence ability due to the storage fo r a long period at a low temperature.