Variability of pollen viability in the flowers and inflorescences of the China aster (Callistephus chinensis Nees) caused by gamma rays in the M1 and M2 generations

Abstract

The influence of gamma rays (within range 3-12 kR) on the variations of pollen viability was investigated in four varieties of Callistephus chinensis Nees in the M1 and M2 generations. The variability, both in generation M1and M2 of the studied character between the plants and flowers within the inflorescence proved to be dependent on the radiation dose and was as a rule higher in populations exposed to radiation than in the control ones. These regularities, however were not equal in the tested varieties. The total variance of pollen viability in the M2 generation was in general lower as compared with that of the M1 generation, whereas the particular variance components showed an extremal dependence (minimum after a 3 kR dose) on the radiation dose.