Observations on Micronuclei Ultrastructure within Broad Bean (Vicia faba) Meristem after γ Ray Radiation

Abstract

The root meristem of broad bean (Vicia faba) fourth day old with γ ray in doses of 50, 100, 200, 300 and 500 rad was irradiated. After 24 hours the root tip was fixed with glutaraldehyde and osmic acid and after that embedded in W vestopal. On several sections micronuclei were present and their ultrastructure could be studied. From ultrastructural point of view the heterochromatinic micronuclei are acentric chromosomal fragments and the euchromatinic ones probably not. A clear separation between micronuclei and other fragments of the normal nucleus was proved.