Radiation Studies in Lens culinaris: Distribution of chiasmata between nuclei and within nuclei in irradiated and non-irradiated populations

Abstract

The effect of the same dose of γ-rays has been studied on the seeds of two varieties of Lens culinaris as regards chiasma frequency.
It appeared that variety macrosperma is a derived type and microsperma, the true wild one.
In variety macrosperma the chiasma frequency is slightly lower than variety microsperma.
The increase in variance ratio (mainly due to increase in the value of mean square between nuclei) in the flower buds of the plants raised from irradiated seeds is likely to be due to more than one karyotype taking part in the formation of the anthers of the flowers.
More karyotypes appeared to have taken part in the formation of the bud chimaera at low doses, in comparison with high doses.
Each plant grown from irradiated seeds had a different chimaeric nature.
In M₂ generation plants appeared to have returned towards normality.
The variety macrosperma has been affected slightly more at the same dose than variety microsperma.