THE COMPARISON OF UNSCHEDULED DNA SYNTHESIS IN GERMINATING WHEAT EMBRYOS TREATED BY Fe1+ IONS IMPLANTATION AND 60Co γ-RAYS IRRADIATION STUDIES ON MUTAGENIC EFFECTS AND MECHANISM OF WINTER WHEAT IRRADIATED BY PROTON Ⅱ.Unscheduled DNA Synthesis of Irradiated Wheat seeds EFFECT OF UNSCHEDULED DNA SYNTHESTS IN SEED EMBRYOS OF WHEAT INJECTED AND PENETRATED BY N~(7+) HEAVY ION