Analysis On Biological Effects And SSR Polymorphism Of Space-Induced Wheat

Seven wheat cultivars included Chuannong 19 and 06Fr785,etc.which were loaded in the "Practice 8" Breeding Satellite and got back from Space were employed to be the experiment materials.Through some tests in the laboratory and reproduction from one generation to another in fields(2006-2008) both physiological changes in the same generation such as seed germination vigor,rate,length of roots and height of young plants and agricultural variations among the different generations were investigated in the research.We analyzed storage protein composition(gliadin and HMW-GS) and microsatellite polymorphisms of the mutants which were found and discussed the mutagenic effects to physiology,biochemistry and molecular biology of the wheat seeds back from Space.Finally,many mutants involved in the short height,the big Spike or the plentiful properties with different storage protein and DNA microsatellite markers were acquired by screening.The main results were as follows:1.The results showed that the germination vigor and germination rate of wheat seeds back from satellite were changed,however,the changes varied from cultivars.The lowest germination rate was 96.83%of KD 11 equivalent to 99.82%of the control.The maximum one is 98.17%of Chuannong 19 equivalent to 132.66%of the control. Germination vigor and germination rate of other cultivars were significantly higher than those of the control.The growth effects in young plants of seven loaded materials were influenced by enhancement or inhibition in which the former was dominant.Different agronomic traits between Sp 1 and Sp 2 generations also existed in both Chuannong 19 and 06Fr785.Sp 2 generation were more diversities than Sp 1 which became an important generation for the screenings of mutants varied in some physiological properties.2.The mutant analyses in seed storage protein of Chuannong 19 and 06Fr785 indicated that both gliadin and HMW-GS were changed in some degree and produced different combination types of HWM-GS subunits from the control.Mutant subunit 1 was found in Site Glu-A1 of both Sp 1 and Sp 2 generation of 06Fr785 and formed a combination type 1/14 + 15/2 + 12 which quality score was 8 and higher than the control and belonged to the advanced combination.8 different bands were separated from gliadin of Sp 1 generation whose polymorphism was 32%and 12 gliadin mutants were acquired. 4 different bands were separated from gliadin of Sp 2 generation whose polymorphism was 15.3%and 5 gliadin mutants were acquired.Sp 1 generation of Chuannong 19 was not acquired any mutant subunits but Glu-B1 and Glu-D1 were found mutant subunits in Sp 2 generation and formed two mutant types of HWM-GS combination which were 1/7 + 8/2 + 12 and null/7 + 9/5 + 10 whose scores were 8 and 6 reSpectively and higher than the control.1 different bands were separated from gliadin of Sp 1 generation whose polymorphism was 5.3%and 7 gliadin mutants were acquired.5 different bands were separated from gliadin of Sp 2 generation whose polymorphism was 20%and 14 gliadin mutants were acquired.3.SSR general markers were involved in the polymorphism analyses of the mutants found in Sp 2 generation of Chuannong 19 and 06Fr785 in order to find out the effects to the DNA mutants of loaded plants.The results indicated that the polymorphisms were amplified by ten pairs of SSR primers in five mutants of 06Fr785 Sp 2 generation. Compared with the control,the polymorphism sites were performed in the addition,the deletion and the different sizes of amplified fragments whose polymorphism frequencies were 0.42%- 4.14%.The polymorphisms were amplified by seven pairs of primers in five mutants of Chuannong 19 Sp 2 generation and performed in the addition and the deletion whose polymorphism frequencies were 0.50%- 6.53%.4.Consequently,seed physiological activities,agronomic traits of progenies,seed storage proteins and molecular levels of plant DNA of wheat seeds back from Space were found variations in some degree among which we could breed the beneficial mutants and provide basic materials for the high yield and high quality wheat cultivars.At the same time,researches on the mutants could accumulate many data used to the further studies on the mutagenesis caused by Space radiation and found more advantages and methods worked for the enrichment of plant resources.