Radiation induced polygenic mutations in Atropa belladona

Variability in polygenic characters released in M1 and M2 generations of Atropa belladonna, a predominantly cross pollinated crop for different quantitative characters was studied. It is found that in M1 generation there is no significant difference in the mean value of the control and populatis treated with 10 and 15 kR gamma rays for almost all the characters studied whereas a treatment of 20 kR resulted in a significant decrease in the mean values. However, variability increased considerably for plant height, leaf length and leaf width in case of irradiated populations. In M2 generation, however, higher means were observed for plant height, tiller number, leaf length and width in treated populations in comparison with the respective ntrols but none of the treatments increased alkaloid content significantly, though there was increase in variability in 10 and 20 kR treated populations. (author)