Regression Analysis of 60CO Irradiation and Pinyangmycin Induced Micronuclei and Chromosomal Aberrations in the Root Tip Cells of Vicia Faba
The induction of micronuclei and chromosome aberrations in the root tip cells of Vicia faba by 60Co irradiation and Pinyangmycin (PYM, Bleomycin A5) was studied. The relationships between the dose and the effects with the two agents were directly proportional. The linear regression equations for 60Co irradiation were: Y = 5.23 + 0.0199X1 and Y2 = 1.92 + 0.0086X2. The equations for PYM were: Y3 = 32.0 + 1903.5X3 and Y4 = 6.382+ 551.5X4. The correlation between the micronuclei and chromosomal aberrations was also good. The linear regression equation for 60Co was: Y5 = 2.036 + 2.219X5; that for PYM was: Y6 = 10.38 + 3.48X6. The results of t test indicate that the correlations in parameters in the six above-mentioned equations were statistically significant (P < 0.01). As compared to metaphase analysis, the result of micronucleus induction by 60Co irradiation was 100 rads, but that of chromosomal aberrations was 500 rads, the ratio of both regression coefficients being 2.1:1. The initial dose of PYM to induce micronuclei was 0.003 g, but the frequency of micronuclei observed was higher than that of chromosomal aberrations. Hence, the induction of micronuclei by irradiation or the chemical action appears more sensitive and the test is easy to perform and inexpensive.