【摘要】 用高传能线密度（LET）的⁵⁶Fe（190keV/μ）、⁴⁰Ar（90keV/μ）离子束及低LET的⁶⁰Coγ射线（0.27keV/μ）照射水稻干种子,对当代幼苗生长、根尖微核细胞率和染色体畸变率的效应,进行了实验分析。结果表明:对比三种辐射源,微核细胞率与染色体畸变率均随处理剂量增加而增加,且呈线性关系。以幼苗的生长半抑制剂量(D₅₀)为指标,三种电离辐射(⁵⁶Fe、⁴⁰Ar离子束和⁶⁰Coγ射线)的相对生物学效应（RBE）比值为6.3∶1.9∶1。以微核细胞率为指标,三者的RBE比较值为11∶4∶1。可见高LET的⁵⁶Fe和⁴⁰Ar比低LET的⁶⁰Co有较高的辐射生物学效应,尤其是在诱发细胞核染色体畸变和微核出现方面,高LET离子束有很高的效率。更多还原

【Abstract】 The dried rice seeds were irradiated with accelerated ⁵⁶Fe, ⁴⁰Ar ionsbeams, or ⁶⁰Co γ-rays at various doses and the effects on seeding growth, as well asmicronuclei and chromosome aberration induction were oberved. The results indicatedthat the seeding height reduction, frequency of micronucleated cells and frequency ofchromosome aberrations all appeared to dose dependent for these three types of re-diation. The RBE value for seeding height reduction. determined at fifty percent ofhight inhibition level, was found to be about 6.3, 1.9 and 1 for ⁵⁶Fe, ⁴⁰Ar and ⁶⁰Coγ-ray respectively. However, the RBE values for the frequency of micronucleated cellswere about 11,4 and 1 for ⁵⁶Fe, ⁴⁰Ar particles, and ⁶⁰Co γ-ray. It appeared that theeffectiveness of high LET radiation in inducing biological effects at the first generationwas higler than that of low LET radiation, especially in inducing the micronucleiformation.更多还原