XVI International Botanical Congess
Stimulation of germination and growth of plants by X-ray irradiation was studied. Dry seeds of Arabidopsis were exposed to low doses (5 to 20 Gy) of X-ray. The irradiation accelerated germination and elongation of shoot when the plants were grown at 10 °C, although it had no effects at 23 °C. Acceleration of germination was also observed when seeds were grown at 23 °C on medium containing H2O2 or radical generator such as methyl viologen. The stimulation by X-ray was accompanied by the increase of O2 uptake of the plants. The effects of X-ray irradiation were inhibited by applying aminoethoxy-vinylglycine, inhibitor of ethylene synthesis. Involvement of respiration and ethylene production in the effects of X-ray irradiation will be discussed.