| Low-energy ion implantation has been considered as a new kind of mutationbreeding and foreign gene delivery techniques. By the means of implantinglow-energy ions into organisms, the biological effects and the functionmechanisms of the technique were investigated by some researchers. Althoughthe researchers have observed some biological effects and revealed'some basicmechanisms since past the decade, they do not master the roles of low-energyion implantation, and the studies on the law of inheritance in the progeniesof the higher plants irradiated by low-energy ions were elementary, especially.In our experiments, choosing the model plant, Arabidopsis thaliana as thetarget of low-energy ion implantation, we observed and counted the biologicaleffects and studied the genetic characters of some varied plants using RAPDassay, to make the fundaments for exploring the interactions betweenlow-energy ions and complicated organisms further. In this research, weobtained the results as follows:Firstly, the germination vigor of M0, M,, and M2 seeds irradiated by the different doses of low-energy N* were compared and analyzed in our experiments. The results showed that the germination and seedling formation rates of the treated seeds and their offspring seeds were lower than that of the control and the rates decreased with the implantation dose intensification. Furthermore, the germination and seedling formation rates of the seeds treated with the dose of SOX 1015N7cm2 were only 7. 81% and 58. 82% in those of the control plants respectively. All showed that low-energy ions cause the seed germination vigor to decrease.Secondly, we compared and analyzed the growing state, plant height, flower shape and seed setting ability, etc, of M2 tube seedlings and M3 greenhouse plants treated with low-energy N* . We found that the growth rates of M2 tube seedlings and M3 greenhouse plants were lower than that of control and the growth rate decreased with the treated doses from 60X1015, 40X1015 to 80 X1015. Vfe also found that many phenotypic variations appeared in M2 tube seedlings, including yellowing, lethality, semi lethality, morphological variation (such as leaf and flower shape variations, plant height variation, etc). Not only was the yellowing serious with a yellowing rate of 22.22% in the plants irradiated with the dose of 80X10'5, but the plants all were dwarf with the height of 6cm, 5. 79cm and 3. 78cm from M,, M2 to M3 respectively which cannot reach 1/3 height of the control averagely. The seedlings irradiated by 80 X1015 NYcm'gave birth to some flower buds without floral shoots and their seed setting rate was lower than that of control obviously. Some M3 plants irradiated by 60X1015 NVcm2grow into bunches which did not appear in M, and M2. Moreover, some phenotypic variations could be inherited stably in subsequent generations. For instance, the dwarf character in the plants treated with the dose of 80 X1015 was stable in inheritance in consecutive three generations. Thus it can be seen that low-energy ion implantation causes developmental state changes and phenotypic variations and some changes and variations can be inherited stably.Thirdly, we compared and analyzed the callus induction and salt-tolerance of leaf explant from M2 tube seedlings irradiated with the different doses of low-energy N*. We found that low-energy ion implantation influences the callus induction, and the higher dose of N* can inhibit the callus induction, but the lower dose can promote it. The callus salt-tolerance was correlative with the implantation doses and the salt-tolerant capability decreased or increased compared to control plants. It showed indirectly that low-energy ion implantation results in physiological state to change and produces complicated physiological effects in Arabidopsis thaliana.Finally, we did RAPD assay using Mj tube seedlings irradiated with'the dose of 80X1015 and M3 greenhouse plants irradiated with the dose of 60X10'" as experiment materials and found that the amounts...
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