AZIDE MUTAGENESIS IN RICE - EFFECT OF CONCENTRATION AND SOAKING TIME ON INDUCED CHLOROPHYLL MUTATION FREQUENCY

The mutagenecity of sodium azide in rice with reference to the effects of concentration and pre-treatment soaking time was studied. Soaked seeds of cv. China-45 were treated with 5 × 10-4M, 10-3M and 2 × 10-3M azide concentrations in 0.1 M phosphate buffer at pH 3. In the soaking experiment the duration of soaking varied from 4 to 60 hr and the seeds were treated with 10-3M azide solution. Mutation frequency as well as the biological damage showed a linear response to the increase in the concentration of azide. Azide induced maximum mutations in rice seeds pre-soaked in water for 4-12 hr; mutation frequency gradually declined, however, with further increase in the duration of soaking. Long soaking periods adversely affected the azide mutagenecity in rice. © 1979.