Combined treatment of Crepis capillaris cells with ethylene imine and gamma-rays at different stages of mitotic cycle

The effect of combined treatment of cells of Cr. capillaris seedlings with ethylenimine (EI) and γ-rays was studied in two consecutive celldivisions. Treatment with the mutagens in the G1 phase of the cell cycle led to a superadditive effect in diploid cells. When the repeat exposure to γ-rays was done in the S- and G2-phases, the effect was additive. The number of chromosome aberrations in tetraploid cells did not exceed the additive level in all variants of the experiment