高能混合粒子场诱变小麦的细胞学效应研究

CYTOLOGICAL EFFECTS OF MIXED PARTICLE FIELD IRRADIATION IN WHEAT

利用北京正负电子对撞机直线加速器E2束流打靶产生高能混合粒子场,以0、109、145、1952、84和560Gy的剂量处理两个冬小麦品种ZY9和ZH7,并与相同剂量的60Coγ射线相比较,研究其细胞学效应。试验结果表明,混合粒子场辐照小麦种子可抑制根尖细胞有丝分裂,诱发染色体出现单微核、双微核、多微核、环状染色体、落后染色体、游离染色体、染色体断片等多种畸变类型。混合粒子场与γ射线诱发的微核畸变率和染色体畸变率均存在明显的剂量效应,但混合粒子场的损伤效应明显高于γ射线。混合粒子场可诱发高频率的环状染色体和染色体断片,显示出混合粒子场处理小麦具有比γ射线处理更高的相对生物学效应。

Dry seeds of two genotypes of winter wheat ZY9 and ZH7 were irradiated by mixed high-energy particle field with different doses of 0, 109, 145, 195,284 and 560Gy, which was generated from E2 beam lines of LINAC of Beijing Electron Positron Collider. The cytological effects on root tip cell of wheat seeds were studied with the same dosage of γ-rays irradiation as a control. The results showed that the irradiation of mixed high-energy particle field inhibited mitoses and produced various chromosomal aberrations such as micronucleus, chromosome bridges, circular chromosomes and dissociative chromosomes in root tip cells of wheat with significant dose-effects. Higher rate of cytological damages and percentage of chromosome circles and fragments were found in the mixed particle field irradiation than in γ-rays irradiation, indicating in the relative higher biological effects of irradiation of mixed high-energy particle field than those of γ-rays in the M1 generation of wheat.