Drought Resistance Study Of Offspring Obtained By Transferring Into Wheat Mediated By Ion Beam

Wheat (Triticum aestivum), whose planting area and gross production are only second to paddy's in China, is the major food crop in the north. Most areas in north China are in the arid and semi-arid state under the influence of the climate. Drought is one of the crucial constraints to the production and development of wheat both in spring wheat reign and winter wheat reign, so the drought resistance has always been an important breeding objective. The drought-resistance mutants of wheat are got by using the method of ion-beam mediated transformation and some special variation materials come into being after years'seeds selection. The appraisal of the drought resistance and related studies of these variation materials also have been done in this experiment.1. Study on the effects of ion-beam mediated transgenic mutation by using wheat's segregating population as transgenic receptorBy using the seeds of two F2 generation segregating population of hybrid combinations as ion-beam mediated transgenic receptor respectively, the variation effects caused by ion-beam mediated transgene are analyzed. It has been found that ion-bean mediated transformation has different influence on different receptors' budding rates from the experiment of agronomic traits and qualitative characters. For example, it can make the budding rate of F2 segregating population's seeds decrease obviously in Hybrid Combination 1.After segregating population's seeds treated with ion-beam mediated transformation, the variation coefficient of its some characters will increase significantly, i.e. the mutant spectrum of characters widens. That shows it is good for seeds selection to use the seeds of segregating population as the receptor of ion-beam mediated transformation. Meanwhile, it demonstrates the average of the high strain and the main spike length has the trend to decrease compared with the control. This may, to some extent, have something to do with the damage effect of ion implantation.2. Study on the drought resistance of the main growth period of ion-beam mediated and exogenous DNA transformed wheat variantThe analysis of relative germination percentage and relative germination rate of 12 variation materials'germination periods, among which the relative germination percentage and relative germination rate of variation material 5504,5606,5626 are higher than control materials', indicates that the drought resistances of the seeding stage of those materials (5504,5606,5626) are all better than control's and the length of coleoptile and main radicle of all variation materials are not sensitive to water yet bud length is sensitive to water.The germplasm resources are inspected during different growth periods for drought resistance according to the correspondence between develop-mental stage of yield components and phenological phase in wheat. To get a knowledge of variation materials'drought resistance during different growth periods, the whole-growth-stage water stress of variation materials and study of corresponding yield index have been made. Some differences of agronomic traits between variation materials have been found after the investigation, significance analysis, variance analysis, and multiple comparisons about agronomic traits such as height, tiller number, fertile spikelet number, sterile spikelet number, kernel number, and 1000-grain weight on the condition of whole-growth-stage water stress and normal irrigation respectively. The key indicators' drought index of variation material 5402 and 5486 are greater than 1, which shows the materials' overall drought resistance has been improved.3. RAPD analysis of progeny of variant wheat with ion-bean mediated exogenous DNAFrom the RAPD analysis of ion-bean mediated progeny of variant wheat, it has been found that bonds of the variation materials are significantly different from control, witch shows the variant plane of ion-bean mediated exogenous DNA progeny of variant wheat mutated in DNA level.The RAPD analysis of variation material 5647 and eleven other materials with hexaploid tritical and oat as donors receptively shows the twelve variation materials have increased by 780 bonds and among them 328 with a proportion of 42.05% shows polymorphism. The bonds'mutation rate of variation materials is 25.35% minimum and 74.24% maximum. The drought resistance of material 5402 and 5486 are high and their mutation rates are 39.39% and 36.36% respectively. However, the mutation rate of 5563 is as high as 74.74%.