Radiation exposure of barley seeds can modify the early stages of plants' development.

The reactions of barley seeds (Nur and Grace varieties) in terms of the root and sprout lengths, germination and root mass were studied after γ-irradiation with doses in the range of 2-50 Gy. The dose range in which plants' growth stimulation occurs (16-20 Gy) was identified. It was shown that increased size of seedlings after irradiation with stimulating doses was due to the enhancing pace of development rather than an earlier germination. The activity of the majority of the enzymes studied increased in the range of doses that cause stimulation of seedlings development. The influences of the dose rate, the quality of seeds, their moisture and time interval between irradiation and initiation of germination on the manifestation of the effects of radiation were investigated. The experimental data on the effect of γ-irradiation on seedlings development were significantly better explained by mathematical models that take into account the hormetic effect.