Abstract
Comparative karyokinetic response of 2n and 4n Trigonella foenum-graecum to gamma rays has been discussed. There is inverse correlation between ploidy level and stimulatory dose. Maximum availability of metabolites due to radiations stimulation in 2n at 60 krad has been suggested as a cause of excessive stimulation. Peaks have been observed in growth., dividing cell and aberration frequency. Cellular heterogenity with regard to radiosensitivity have been discussed. The differential assortment of cells carying aberrations is one of the reason of getting peaks in aberration. Certain biochemical or physiological factor accounts for differential sensitivity of 2n and 4n. Replication of DNA has been supposed to be one of the factor for slower growth rate and division frequency in 4n. Correlative study of ICV and radio-sensitivity have been made which reveals that despite larger ICV the 4n are radioresistant at the parameter of growth, dividing cells and initiation of second-ary roots although aberration frequency is higher in 4n. Higher ICY may explain greater chromosomal damage in tetraploids.
