Effects of 60Co irradiation on embryogenesis callus iduction of zoysiagrass

Caudexes of three zoysiagrass (Zoysia spp.) were used as explants in this experiment, and these explants irriadiated by 60Co ray at dosage in the range of 5~40 Gy. The results showed that the callus induction and embryogenesis callus induction were both increasing with the low dosage from 5 to 20 Gy. The critical dosage (dosage rate was 1.0 Gymin-1) of callus induction was 25 Gy, the callus induction decreased quickly when the dosage was higher than 25 Gy.The critical dosage (dosage rate was 1.0 Gymin-1) of embryogenesis callus induction was 20 Gy, the embryogenesis callus induction of three zoysiagrass at 20 Gy were 37.5 %(QJ), 76.5 %(YJ), and 63.6 %(MJ). The half lethal dosage of the callus induction irradiated on these three zoysiagrass was 30 Gy.