Effects of dimethipin on α-amylase activity of barley seeds were investigated. In the treatments of 1 μM and 10 μM dimethipin, the indexes of germination were reduced to 17% and 24 % respectively. After seed germination, dimethipin was added to germinated seedlings and then the seedlings were kept to measure seedling length under illumination for 7 days. In control, the length of seedling was 5.7 cm, but in the treatments of 1 μM dimethipin and 10 μM dimethipin, seedling lengths were 5.5 cm and 1.2 cm respectively. In the relationship between dimethipin concentrations and α-amylase activities, there was a linear curve. The more dimethipin was added to the seeds, the more α-amylase activities were inhibited. In the treatments of 1 μM dimethipin and 10 μM dimethipin, α-amylase activities were reduced to 33% and 71% respectively. Dimethipin also inhibited α-amylase activities increased by gibberellin and the content of soluble protein. Therefore, it could be suggested that dimethipin might inhibit directly the activities of hydrolysis enzymes including α-amylase or the expression of α-amylase genes as germination and seedling growth were severely disturbed.

• 이준상(충북대학교 과학교육학부) | Joon Sang Lee Corresponding Author