Radiation-induced organogenesis: effects of irradiated medium and its components on tobacco tissue culture

Gamma irradiated medium induces the formation of buds in non-irradiated dark growth tobacco callus (Nicotiana tabacum Var. Wisconsin No.38). Experiments were conducted to determine the component(s) of the medium that is effective in this radiation-induced organogenesis. Fraction of medium were irradiated singly and in combination, then combined with non-irradiated fractions to form the complete growth medium. The results showed that irradiated indoleacetic acid (IAA) was not the effective component in the induction of organogensis. Omission of IAA from the medium resulted in the formation of buds, as expected. Irradiated myo-inositol induced organogenesis more consistently than the other irradiated components. The age of the inoculum tissue and its passage number from the tobacco stem affected the potency of the tobacco callus to organise. (author)