The ESR spectroscopic features and kinetics of the radiation-induced free radicals in maize (Zea mays L.)

A detailed ESR investigation on the characteristic features and kinetic behaviors at different temperatures of the long-life free radicals induced in gamma irradiated ground maize cultivated in Turkey was carried out in the dose range of 0-5.0 kGy. Unirradiated ground maize exhibits a weak, broad single-line ESR spectra centered at g = 2.0048 originating from a radical species of unknown structure called as radical III in this work. Irradiation produced two more radicals called radical I and radical II, beside radical III. The radicals (I, II and III) follow complicated kinetics. Room and high temperatures signal intensity decay data along with data derived from room temperature ESR spectra were used together to calculate spectroscopic features of the contributing radicals. A model based on three radicals of different features found to describe best experimental results obtained for irradiated maize. Dosimetric properties of maize in the studied dose range were also reported. (C) 2004 Elsevier Ltd. All rights reserved.