Purpose: To demonstrate the abscopal mutagenic effect of low-energy-ion irradiation in dormant plant seeds, and its dependence on the targeted portion of seeds.
Materials and methods: Arabidopsis thaliana-lines transgenic for b-glucuronidase (GUS) recombination substrates and A. thaliana RADiation54 (AtRAD54) promoter::GUS were adopted. The seeds were irradiated from four specialised orientations with 30 KeV (40)Ar(+) ions. The homologous recombination frequency (HRF) and the expression levels of the AtRAD54 genein non-irradiated aerial plants were measured. Moreover, several post-embryonic developments, such as growth of primary roots, differentiation of root hairs, and germination of seeds and growth of true leaves, were also analysed.
Results: It was shown that low-energy-ion irradiation of seeds led to significant increases in HRF in the non-irradiated aerial parts of irradiated plants and the aerial parts of naïve plants from irradiated progenitors. The low-energy-ion irradiation was also shown to induce an elevated expression of AtRAD54 gene in aerial plants, and to inhibit the post-embryonic developments of seeds. Moreover, the changes in HRF, expression level of the AtRAD54 gene and post-embryonic developments depended largely on the orientation of seeds with regard to low-energy-ion irradiation; and the root apical meristem (RAM)-orientated irradiation exhibited the largest effects on all biological endpoints assayed here.
Conclusions: Low-energy-ion irradiation can induce an abscopal mutagenic effect in dormant plant seeds, the extent of which depends greatly on the targeted portion of seeds.