Chromosomal aberrations and micronuclei induced in onion (Allium cepa) by gamma-radiation.

The Allium-test is commonly used to assess genotoxicity of chemical and physical factors. In the present study, the roots of germinating onion (Allium cepa) were exposed to 0.02-13 Gy of γ-radiation. The dose dependencies of the frequency of chromosomal aberrations and micronuclei were nonlinear. An increase in the frequency of chromosomal aberrations in germinating seed root cells was first found under exposure to low doses of γ-radiation (0.05 and 0.1 Gy). Micronuclei inductions at low doses of radiation were not significantly different from the control. Our study suggests that germinating onion seed roots are a sensitive bioassay material for assessing the genotoxic effects of low-dose γ-radiation.