[Genetic effects in plant populations in the zone of the Chernobyl accident]

During 6 years, starting from 1986, the monitoring of the dynamics of the frequency of embryo lethal and of chlorophyll mutations was carried out in arabidopsis populations in areas with different levels of radioactive contamination by the Muller embryo-test in the 30 km of ChNPP. The dose rate of chronic irradiation in the examined areas varied from 0.014 to 17 nA/Kg. Monitoring of the dynamics of the mutation process in natural arabidopsis populations showed the correlation between the level of the mutation process and the dose rate of chronic irradiation. The genetic effects of different levels of radioactive contamination were estimated by determining the frequency of mutations occurred in this generation and by calculating the dose of irradiation of one was found. That the dependence of the mutation frequency on the dose of irradiation presents a power function with a power index less 1, which suggests a higher efficiency of low radiation doses per unit dose. Possible explanations of this phenomenon are considered in the work. The studies of cytogenetic effects in chronically exposed Crepis tectorum populations in the zones of the Chernobyl accident showed that starting from the second year after the Chernobyl disaster there appeared plants with an altered karyotype and their frequency of chromosome aberrations correlates in root meristem cells.