Induction of mitotic aberrations by Argon ion lasers in Vicia faba L. and Allium cepa L.

Abstract

A comparative study of the effect of laser in inducing chromosomal aberrations at 488 nm was done in Vicia faba L. (faba bean) and Allium cepa L. (onion) with Argon ion laser (Spectra Physics Model 171). Seeds and bulbs of V. faba and A. cepa were subjected to laser irradiation by 488 nm excitations from Argon ion laser source at power levels 200 and 400 mW with power densities 2.25 mW cm-2 and 4.49 mW cm-2 and different exposure times ( 10, 20, 30 & 40 ..... tc) similar to the effect of other physical and chemical mutagens, laser caused a dose dependent decrease in mitotic index and a rise in mitotic aberrations when compared to the control . In both plant species, mutations were observed in all stages of mitotic cell cycle . The total percentage of aberrations was two fold higher at 400 mW than at 200 mW exposure.