Ionizing treatments were applied at 5Gy, 10Gy, 50Gy, 100Gy and 500Gy to mushroom mycelium (Lentinula edodes) in order to assesss the effect of the gamma-ray radiation. We mutated by gamma irradiation, 12 strains were isolated. 9 strains of 12 strains were appeared antagonistic interaction on solid medium. Growth rate of mycelium in JMIR-3 and JMIR-6 strains were similar to their control. But, the growth rate of strain JMIR-1, JMIR-2, JMIR-4, JMIR-5, JMIR-7, JMIR-8, JMIR-9, JMIR-10, JMIR-11 and JMIR-12 had generally different compared to control. In the sequence of ITS region of selected strains, it was revealed that the total length ranged from 696 to 780bp. The reciprocal homologies of the ITS region sequences in 5Gy irradiation group (JMIR-5, JMIR-6, JMIR-7 and JMIR-8) and 10Gy irradiation group (JMIR-9, JMIR-10, JMIR-1 and JMIR-12) indicated 99%. The reciprocal homologies of the ITS region sequences in 500Gy irradiation group (JMIR-1, JMIR-2, JMIR-3 and JMIR-4) indicated from 95 to 99%. It seemed that mycelium growth and ITS sequence could be changed the irradiation dose of the gamma-ray radiation.

• Kim Kwang-Sang(Jangheungcounty Mushroom Research Institute, Jangheung 529-851, Korea)
• Kim Kyung-Je( Jangheungcounty Mushroom Research Institute, Jangheung 529-851, Korea) | Kim Kyung-Je
• Ban Seung-Eon( Jangheungcounty Mushroom Research Institute, Jangheung 529-851, Korea) | Ban Seung-Eon
• Kim Yu-Seon( Jangheungcounty Mushroom Research Institute, Jangheung 529-851, Korea) | Kim Yu-Seon
• Hong Seul-Gi( Jangheungcounty Mushroom Research Institute, Jangheung 529-851, Korea) | Hong Seul-Gi
• Jang Eun-Kyoung( Jangheungcounty Mushroom Research Institute, Jangheung 529-851, Korea) | Jang Eun-Kyoung