Received: 05-08-2021 / Accepted: 29-10-2021
This study was carried out to effects of gamma ray irradiation of irradiation Co60 source forsome local and imported rice accessions. This experiment was designedwith 3 dose (200Gy, 300Gy and 400Gy) on the mutagenesisof three rice (12% seed humidity). At generation M1, the results showed that the seed germination and survival percentage of all rice accessions decreased with the increase of the irradiation doses. Mutated plants with shorter growth duration, lower plant height, more upright flat leaves appeared, greater tillering capacity with high mutation frequency at irradiation dose of 200Gy, 300Gy for imported rice varieties NN1, NN3 in the M2generation. The mutation appeared with very low frequency when irradiating the local rice variety Khau Mang. Selection on M3generation of 200Gy and 300Gy irradiation treated varieties NN1 and NN3 picked up some promising rice lines with short growth duration, short plant height, more upright flat leaves appeared and high tillering capacity. To sum up, gamma Co60irradiation at 200Gy and 300Gy dose on dried seeds could renovated some agronomic traits such as growth duration, plant height, flag leaf morphology and tillering capacity on two imported rice varieties NN1 and NN3.