STUDIES ON THE FLOODING TOLERANCE DURING SEED-GERMINATION OF SOYBEAN (GLYCINE-MAX (L) MERRILL) .3. EFFECTS OF SEED-COATING TREATMENTS ON THE STIMULATION OF SEED-GERMINATION UNDER FLOODING CONDITION

The objectives of the study were to understand the germinability of peroxide coated seeds of soybean under flooded condition. The mechanism of the coating effect was also examined. Both varieties of Kaoshiung 8 and VS 205 were used as materials. The results were summarized as follows: The treatments of seeds coated with both captan and binder-methylcellulose had the greatest effect on the protection of seed germination under flooding. The treatment of seed + captan or seed + methylcellulose was not as good as prior treatment, and the treatment - seed only (without coating any material) had the lowest germination percentage. Seed coated with peroxides, the treatment seed + captan + methylcellulose + ZnO2 or CaO2 had the greatest effect on the stimulation of seed germination, but no significant effect by coating with Ca(OH)2. Two percent of ZnO2 or CaO2 coating was better than any other concentration higher than 2%. Seed coated with methlcelluslose could reduce the rate of water uptake and electric conductivity. The treatment of seeds coated with ZnO2 or CaO2 could also reduce the activity of alcohol dehydrogenase and the content of accumulated alcohol. Thus, seed-coating treatments could be confirmed to stimulate seed germination of soybean under flooded condition.