Abstract
To analyze the differences in the rate of seedling emergence and seedling height among rice ecospecles at different soil reduction levels, five blocks were prepared containing soils with different amounts of starch, i.e. 10, 20, 30, 83 and 167g per block, and no starch addition block (control) was also prepared. The mean rate of seedling emergence and seedling height were increased by the addition of a maximum amount of 20g starch per block in the three ecospecies. However, the mean rate of seedling emergence markedly decreased with the increase of the amount of starch added over 20g per block. The mean rate of seedling emergence in the japoeeica cultivar group was higher than that in the iudica cultlvar group at all the redox potential levels, whereas that in the javanica cultivar group was intermediate. However, the rate of increase and/or decrease of the mean seedling height with changes in starch amount added was almost similar in the three ecospecies.
