The present study deals with the mitotic consequences of gamma radiation induced chromosome breaks in L. sativus and V. ervilia following seed irradition. Various types of mitotic anomalies were encountered.
These included:
1. Single, double, triple, multiple, X-shaped and interlocked bridges. The double bridges lasted very long persisting upto the late telophase and often left pear-shaped projections in the daughter nuclei marking their positions.
2. Centric and acentric fragments in the metaphase and laggards in the anaphase were present. The fragments were of different lengths and the majority of them were in pairs. There were also some rings, minute deletions, dicentric chromosomes and chromatids present.
3. Unequal length of metaphase chromosomes showing much more variation in length than is observed in the normal karyotypes.
4. “Condensed” and “non-condensed” micronuclei in the interphase cells were observed and there was increasing evidence indicating that some of these micronuclei divide and go to the daughter nuclei.
5. Degenerated cells having little chromatin material and showing less stainability were present.
6. Giant cells often having about double the size of the ordinary root meristematic cells were present only in the species V. ervilia.
Probable causes of the production of mitotic abnormalities following seed irradiation treatment were discussed in the light of the findings of other workers.