Effect of oxygen on genetic damage in barley seeds induced by γ-radiation

Abstract

The sensitivity of Bonus barley seeds to γ-radiation is decreased in the order: 4.7 % H2O, 50 kg cm-2 02>4.7 % H2O with soaking in oxygenated water >8.3 % H2O, soaking in oxygenated water. The same order of decreasing radiosensitivity was found for mutation frequency, sterility, seedling height reduction and root length reduction. The nitrogen-conditioned seeds with 14.2 % water content are the most protected. The genetic end points: chlorophyll mutation and sterility, exhibited oxygen enhancement ratio (OER) in the range of 5–7, which is in the same range as seedling height reduction. The latter character is mostly physiological. The results are discussed in terms of a role of damage to membranes or DNA-membrane-complexes being in some way involved in the mutagenesis of low-LET radiation in barley seeds.