The vertical heterogeneity of 137Cs and 90Sr distribution in the main root of seedling with prevailling concentration of radiocesium in meristem zone and radiostroncium in elongation zone is established. The obtained data have allowed to calculate the dose loads on plant critical tissue in conditions of radionuclide pollution. The negative influence of 3.7 · 105 Bq/kg 137Cs soil pollution on seed germination and growth rate of onion seedlings is shown. At levels of soil pollution about 3.7 · 102 - 3.7 · 105 Bq/kg the increasing of mitotic index of meristem tissue of the onion seedling main root is shown. The level chromosome aberration in meristem cell at ninth day was about 241, 216 and 151 % for soil with activity 3.7 · 104 , 18.7 · 104 and 3.7 · 105 Bq/kg correspondingly. The root growth rate and mitotic index in irradiated variants exceeded with control level, that denoted on restoration and radioadaptation processes. The essential difference between the quantitative characteristics of radiocesium and radiostroncium cytogenetic action is not revealed.
Grodzinsky et al. (Mon,) studied this question.