Modification of Radiation-induced Oxic and Anoxic Damage by Caffeine and Potassium Permanganate in Barley Seeds

We show that both the immediate and post-irradiation oxygen effects in barley seeds decrease in magnitude in the presence of potassium permanganate and caffeine. This implies that these two types of oxygen effect have features in common. With the removal of the radiation-induced oxygen-sensitive sites, by anoxic hydration, caffeine potentiates the oxygen-independent component of damage, in seeds irradiated in a dry or pre-soaked state. Potassium permanganate, on the other hand, enhances the anoxic radiation damage only in seeds irradiated in a dry state. The possible mode of action of KMnO₄ and caffeine in barley seeds is discussed.