Abstract
The effect of different seed pretreatment, coating materials, and amounts of coating materials on hardness, germination characteristics and color of coated seeds were evaluated to clarify how each factor contributes to protect the seed from bird damage. The coating material of iron-coated seed was more closely adhered to seed than that of peroxide-coated seed making it difficult to flake off, and the iron-coated seed was very hard. The hardness of iron-coated seeds was not due to the thickness of the iron film, but to seed moisture, and was suggested to decrease rapidly along with water absorption by the seed before germination. Decreasing coating ratio of iron material did not affect the color and hardness of the coated seeds but hastened germination. Therefore it is suggested that thinly iron-coated seed germinated early after drainage in the field is prone to be damaged by birds.
