We have set an experiment involving the radiation of 7-day-old seedlings of the 19-3-3 maize line to study these phenomena. A dose of 6 Gy, which is sublethal for seedlings, was applied for a control effect. The radiation was accomplished through a hard g-irradiation using a PXM-g-20 unit. Following a 10 min radiation, the Petri dishes containing the seedlings were exposed 1, 5, and 10 min to a 2 kW electric field. Rootlets were fixed to estimate chromosome aberrations and the findings were compared with control, in which the seedlings were not exposed to postradiation treatment. The rootlets were fixed at different periods, immediately after the treatment (0 min), after 30 min and 90 min to assess the dynamic action of the repair systems.
The number of chromosome aberrations, %
Treatment |
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Control - 6Gy |
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1) 6Gy + 1 min EF |
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2) 6Gy + 5 min EF |
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3) 6Gy+10 min EF |
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The findings are summarized in the table. All the treatments increased
the chromosome aberration with respect to the control.
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