| Ion beam mutation study using high-energy ion beams began in the 1920s. However, at that time, mutations resulting from low-energy ion beams were not recognized. It was not until decades later about 1980s that mutation effects on rice using low-energy ion beams were reported by Yu Zengliang et al.. During the past 20 years, substantial progress has been made in this field of research. Many studies have focused on changes to morphological and cytological traits, isozymes and DNA originating from different mutation materials, and some cultivars in different crops have been generated by exposure to low-energy ion beams, including Wanjing D9055 and S9042 in rice, Wanmai32 and Wanmai42 in wheat and so on. On the mechanism, many research were done including cell sculpting, matter aggradation, energy aggradation, bystander effects and the like. But as a new research realm, a good many challenges were confronted by ion beam bio-engineering, such as improving of treatment methods and equipments, low impact, small treatment colony in one radiation operation and the puzzledom of mechanism etc.. We selected maize as the materials for the application research and mechanism exploring and some results were described as that:①As the highest output food supplies corp, maize is of great importance in the the application and background research realm and fit very much for the research of low energy ion beam implantation because of the five characters found or proved in our experiments:firstly, being diploid plant, maize is smaller and simpler in genome comparing with some other plant such as wheat and so on. Secondly, maize can be free of the seed capsule obstacle to the penetration of ion beam by shucked out of the seed capsule easily than other plant. And so the growth point of maize embryos can be implantated directly and effectively by ion beam for free of seed capsule obstacle. Thirdly, comparing to wheat, rice and other plant, the larger embryo of maize can absorb more ion beam because of its larger surface area. Fourthly, because of its shorter growth period(about 100 days) and the increasing generation technology in Hainan province, that make two or three mutation selection generations in one year possible, maize as the experimental materials of ion beam radiation is efficient that can provide large advantage to enlarge mutant chosen cology and short research period. Fifthly, its strong pollen viability and long existence time, comparing to wheat and rice, made maize pollen mutation by ion beam possible.②A mensuration method to evaluate pollen viability with low energy in maize was established. Several challenges experienced during ion implantation pollen mutation research were overcome, including pollen loss from run-off during vacuum pumping, and high pollen mortality rates. The data showed that a half lethal dose of 1 X 1014N+/cm2 at low-energy 30 keV was most effective for treating maize pollen. Three elite inbred lines were treated in this study. Some mutants such as white anther color, red seed capsules, lethal seed and albino seedling mutants were observed in the MO and M1 populations. The results demonstrated that the pollen treatment with low-energy ion beam was an effectual method in maize mutant breeding.③A method of maize seed embryo proteomics research were established that overcome protein distilled,2-D salt-removed and voltage-hoisted, coloration and so on. The amended method acquired high quality 2-D picture and established good base for the proteomics research of ion beam radiation effects.④Innovation of ion beam radiation effects research. Based on the former research, we studied proteomics research of ion beam radiation effects. Through ion beam radiating treatment of maize seed and proteomics analyzing of treatment seed embryos, some absorbing results were acquired. The vacuum, high temperature and ion of ion beam radiation equipment affected the proteome of the treatment maize seed embryos, and so some protein enzymes answered to the pressure of environment such as smHSP (HSP16.9,HSP17.4),HSP70,LEA3,DHN1 and so on that up-regulated in output and probably related to defence of ion pressure. Some kinds of antioxidant protein enzymes were up-regulated in output such as MnSOD, GST21, peroxidase and so on that probably has been associated with stress tolerance in plants because it neutralizes the reactivity of O-2, which is overproduced under oxidative Reactive Oxygen Species(ROS). The protein degradation enzymes such as 26S-ubiquitin proteosome pathway conjugating enzymes were up-regulated in output probably related to the degradation of denaturalization protein produced by ion beam radiation. Many regulator protein such as Ran,MAPK,PP2A,14-3-3 were up-regulated or down-regulated related to regulation of organism response. Some metabolize enzyme related to sugar, protein, nucleic acid and so on were down-regulated probably related to the damnification of ion beam radiation or seed bourgeon drawback, slow growth and so on. Some gene expression correlative protein or nucleic acid conjunction protein probably related to gene mutation.⑤The heterosis behaved well in maize proteome, especialy in the proteomic induced by ion beam radiation. More differences were discovered in the response of ion beam radiation among the parents and hybrid. The hybrid can endure stronger ion beam radiation than the parents. In proteome, the response of hybrid became more complex and active than the parents. Such as more kinds and quantity of molecule cheapore as HSPs, LEA3,DHN1 and so on so that clear up denature protein efficiently, more kinds more kinds and quantity of antioxidant protein enzymes to neutralize the reactivity of O-2 and so on, more kinds more kinds and quantity of regulator for regulating efficiently. In addition, more little in down-regulated extent in the hybrid metabolize enzymes than the parents probably related to the strong endurance to ion beam radiation.
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