60Co-γ射线辐照对结缕草愈伤组织分化的影响

本试验以3个结缕草（Zoysia spp.）（品）种（兰引3号，马尼拉，青岛）的茎基作为外植体材料，诱导愈伤组织，观察出愈率，然后用不同剂量（5~40 Gy）的60Co γ射线辐照处理愈伤组织，观察其胚性愈伤组织诱导情况。结果表明，较低剂量（15～20 Gy）的辐照处理可以促进结缕草愈伤组织向胚性愈伤组织转化，在这一剂量范围内，3个结缕草（品）种不但可以获得很高的出愈率，同时也可获得较高的胚性愈伤组织形成率。胚性愈伤组织诱导的临界剂量是20 Gy， 此时，兰引3号、马尼拉和青岛愈伤组织的胚性转化率均达到了峰值，分别为76.47%、63.64%和37.5%。3个结缕草品种愈伤组织辐照的半致死剂量为30 Gy。

Effects of 60Co-γ 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 γ 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 Gy·min-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 Gy·min-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.