Rice seeds germinate in the complete absence of oxygen. Under anoxia, the seeds have greater stress in abiotic condition than in aerobic one. Antioxidant enzymes play an important role of ROS(Reactive Oxygen Species) scavenging in various anoxic stress. We investigated the relationship between antioxidant enzymes and early seedling growth of four rice cultivars (Iksan 429, Khaiyan, FR13A, and Nampyeong) under anoxic and aerobic conditions. Rice seeds immersed into a sealed water bottle for 10 days. During anoxia, rates of cleoptile elongation were faster in tolerant varietise Iksan 429 and Khaiyan than in FR13A and Nampyeong. In the anoxic water condition, the activity of SOD in Iksan 429 and Khaiyan increased slightly until 5 days , while that of Nampyeong and FR13A decreased significantly after 7 days. The activity of peroxidase in Khaiyan was higher than that of FR13A. These results suggest that the ability to increase SOD and POX may be one of the determinants in anoxia tolerance of rice.

• Woo-Jae Kim(Department of rice and winter cereal, NICS, RDA) Corresponding Author
• Jong-Cheol Ko(Department of rice and winter cereal, NICS, RDA)
• Man-Kee Baek(Department of rice and winter cereal, NICS, RDA)
• Ki-Yong Ha(Department of rice and winter cereal, NICS, RDA)
• Ji-Young Son(National Institute of Crop Science, RDA)
• Mun-Sik Shin(Department of rice and winter cereal, NICS, RDA)
• Jae-Kweon Ko(Department of rice and winter cereal, NICS, RDA)