氩离子束辐照拟南芥干种子的生物学效应

摘要

To study the biological effects of argon ion beams provided by Heavy Ion Medical Accelerator in Chiba (HIMAC, Program No.13J404) in National Institute of Radiological Sciences (NIRS) onArabidopsis thaliana, the postembryonic development of irradiated dry seeds, such as survival rate, root length, hypocotyls length, plant height and bolting rate, were investigated. The results showed that survival rate, root length, hypocotyls length, plant height and bolting rate decreased with the increasing doses. The variations of genomic DNA fingerprints of the irradiated samples were analyzed by using random amplified polymorphic DNA (RAPD) technique. RAPD results demonstrated that the genetic similarity coefficient between the controls and treatment groups were 0.556~0.944. But the similarity coefficients among treatment groups irradiated with different dosages had no obvious correlations. All the results indicate that M1 seedlings ofArabidopsis thalianairradiated by argon ions has obvious biological effects on both the plant developments and genomic DNA variations.%以拟南芥(Columbia 生态型)为材料,利用氩离子束辐照干种子,通过对存活率、根长、下胚轴长和株高的测定来研究不同剂量的氩离子束辐照对拟南芥的生物学效应.结果显示,随着吸收剂量的增大,拟南芥的根长、下胚轴长和株高都呈现出下降趋势;但存活率在低剂量辐照时无显著变化,高剂量辐照时逐渐降低.运用随机扩增多态性DNA (Random amplified polymorphic DNA, RAPD)技术对氩离子辐照后拟南芥的DNA 指纹图谱进行分析,结果表明,各个处理组和对照组之间的相似性系数在 0.556~0.944 之间,并且相似性系数与剂量之间没有显著相关性.对照组与处理组之间的差异体现为扩增条带数目的减少和增多以及条带亮度的不同.综合分析表明,氩离子束辐照拟南芥干种子产生显著的当代损伤效应,较高剂量下会抑制生长发育,同时引起基因组DNA一定程度的多态性变化.