The low doses of X-rays radiation impact on the photoperiodic pathway genes in plants

The effects of small doses of irradiation on the activity of genes of the photoperiodic pathway were studied. The irradiation of 4 week old plants by X-ray radiation at doses of 3, 6, 9 and 15 Gy with a dose rate of 89 cGy/s and photon energy 6 MeV was carried out. The key genes of the photoperiodic path AP1, GI, FT, CO were selected for the study. The gene expression analysis in real time polymerase chain reaction (PCR) was performed. The statistical analysis of the quantitative PCR results was performed using the REST 2009 software. The relative expression was calculated by comparing the time when the experimental and control samples fluorescence curves cross the threshold. The studies indicated that plants irradiated with X rays in a dose up to 15 Gy started the flowering phase earlier then the control group. In addition, the expression of the key flowering genes increased in experimental plants. During the experiments, a nonlinear dependence of the change in the genes expression of the photoperiodic path in plants irradiated with low doses of radiation was found. The reaction from the mechanism of the flowering determination to low doses of radiation is not specific compared with the response to other abiotic stress factors.