title: Gamma radiation effects on seed germination, growth and pigment content, and ESR study of induced free radicals in maize (Zea mays).
abstract: The effects of gamma radiation are investigated by studying plant germination, growth and development, and biochemical characteristics of maize. Maize dry seeds are exposed to a gamma source at doses ranging from 0.1 to 1 kGy. Our results show that the germination potential, expressed through the final germination percentage and the germination index, as well as the physiological parameters of maize seedlings (root and shoot lengths) decreased by increasing the irradiation dose. Moreover, plants derived from seeds exposed at higher doses (≤0.5 kGy) did not survive more than 10 days. Biochemical differences based on photosynthetic pigment (chlorophyll a, chlorophyll b, carotenoids) content revealed an inversely proportional relationship to doses of exposure. Furthermore, the concentration of chlorophyll a was higher than chlorophyll b in both irradiated and non-irradiated seedlings. Electron spin resonance spectroscopy used to evaluate the amount of free radicals induced by gamma ray treatment demonstrates that the relative concentration of radiation-induced free radicals depends linearly on the absorbed doses.
authors.affiliation: Faculty of Environmental Science and Engineering, Babeş-Bolyai University, Fântânele Str., No. 30, 400294, Cluj-Napoca, Romania. delia.marcu@yahoo.com
authors.forename: Delia
authors.initials: D
authors.lastname: Marcu
authors.forename: Grigore
authors.initials: G
authors.lastname: Damian
authors.forename: Constantin
authors.initials: C
authors.lastname: Cosma
authors.forename: Victoria
authors.initials: V
authors.lastname: Cristea
mesh_terms: D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals / Q000378:metabolism*; D005720:Gamma Rays; D018525:Germination / Q000528:radiation effects*; D010788:Photosynthesis / Q000528:radiation effects; D010860:Pigments, Biological / Q000378:metabolism*; D011836:Radiation Tolerance; D012639:Seeds / Q000254:growth & development* / Q000528:radiation effects*; D003313:Zea mays / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects*
chemical_list: D005609:Free Radicals; D010860:Pigments, Biological