The effect of varying of gamma rays 60Co on the dynamics of seed germination and survival of China aster (Callistephus chinensis Nees) seedlings. Part 1

Studies were undertaken on the effect of gamma rays on germination of aster seeds in laboratory conditions and a greenhouse, as well as on the dynamics of seedlings survival after 10, 20, 30 and 40 days. In laboratory conditions negative effect of radiation on seed germination was noted already four days after sowing. However, this effect was only transitory and after 10 days decreased germination ability was observed only in case of ''Goplana'' variety, at radiation doses of 24 and 30 kR. In greenhouse conditions higher radiation doses decreased germination ability of most varieties under study and prolonged germination time. At 24-50 kR inhibition of growth and development of seedlings - at the stage of cotyledon - was noted in all varieties under study. Lethal effect of radiation occurred after 20 or 30 days and increased with time. Level of LD100 after 40 days varied in particular varieties from 12 to 18 kF. Reaction of particular varieties under study was also differentiated. (author)