IDENTIFICATION AND DOSE ESTIMATION OF IRRADIATED ONIONS BY CHROMOSOMAL STUDIES

Post-irradiation identification and imparted dose determination are ve ry much; required to build the consumer confidence and for appropriate enforcement of the technology by the food inspectors. Towards this en d, chromosomal aberration studies were attempted. Onions irradiated to different doses of gamma radiation, viz., 30, 60, 90, 120 and 150 Cy were scored for various types of chromosomal aberrations. The aberrati ons were found to increase with the dose and maximum type of aberratio ns were observed at 150 Gy. Single minutes, followed by double minutes were found to have outnumbered the other types at all the doses of ir radiation. Tetracentrics were observed only at 150 Gy. The proportion of dicentric chromosomes appeared to be the most reliable parameter to estimate the irradiation dose given to onions.