【摘要】 ⁶⁰Co-γ射线50R 处理小麦幼穗对花粉愈伤组织的诱导有刺激作用。250—2000R 处理不同程度地抑制了花粉愈伤组织的诱导。细胞学观察表明,低照射量有刺激作用,使启动花粉增多,雄核离体发育过程中解体死亡数减少,导致诱导率提高。250和500R 照射量使前期启动花粉增加,但中途停留在二核状态的花粉较多,三核花粉和多细胞花粉多数解体死亡,致使诱导率低于对照。750R 以上各处理,启动花粉也有增加,而进入二核和三核阶段后大部分停止分裂,解体死亡数超过对照,多细胞花粉很少,诱导率明显降低。更多还原

【Abstract】 By pretreating the anthers with low dosage(50R)of gamma radiation,the stimulating effect on the pollen callus induction of wheat was observed,whereas inhibition was noticed in the case of treatments with dosage between 250R and 2000R.The cytological studies showed that irradiation with low dosage caused a significant increase of the first mitoses and a decrease in the number of the dead pollen grains in the culture,thus resulting in an increase of induction frequencies of pollen callus.Irradiation with 250R or 500R caused an increase of the first mitoses in the initial stage of the culture,but the irradiated pollen grains stayed in binucleate state more than non-irradiated ones.The irradiated pollen grains in trinucleate and multinucleate states died even more than those non-irradiated ones,resulting in a decrease of the pollen callus induction as compare with the control.Irradiation over 750R also caused an increase of the first mitoses,but most of the pollens of binucleate and tri- nucleate state stopped division,hence the number of the dead pollens was more than that in the control,while multinucleate pollens were very few.Consequently, the induction frequency of pollen callus showed a significant decrease.更多还原