Comparative assessment of Gamma rays and EMS induced chromosomal aberrations in Brassica Genotypes

Abstract

Mutagenic effect of gamma rays and ethyl methane sulphonate (EMS) on mitotic indices and structural chromosomal aberrations were studied using three different doses/concentrations of mutagens along with a control. It was found to mitotic indices decrease with increasing the doses of mutagens in all the two genotypes T-9 and PT-303 of Brassica campestris. The mutagens were also found to induce high frequency of chromosomal changes like c-metaphase, chromatid bridges, chromosome fragments, laggards etc. Their frequencies were also found to increase with increase of the doses. Comparative study of the two treatments showed that mitotic indices were much retarded by gamma rays in comparison to EMS and abnormality percentage was higher in EMS in comparison to gamma rays.