Study On Mutagenic Effects Of Space Environment On Wheat M₂

The wheat seed were treated by space flight . Photosynthetic rate and other physiological characteristics were measured during heading , blooming ,filling stage in wheat M₂ of Shaan 253 and Xinong 1043 . At the same time the agronomic characteristics and growth situation were observed, and obtained 12 mutation strsins . The effect of space environment mutation and ⁶⁰Coγ-ray irradiation on protect enzyme isozymes were studied by the technology of electrophoresis . The result is as follows:1. The effects are different for ⁶⁰Coγ-ray and space environment mutation on the protect enzyme of wheat seeding. The number of protect enzyme isozyme bands changed little by 100Gy radiation, and as same as space environment mutation.But it changed obviously by 300 and 500Gy radiation, and the original bands disappeared ,new bands appeared.2. The content of MDA and the activity of POD,CAT,SOD are measured at heading , blooming and filling stage After carried by spaceship. Correlation analysis show that POD is the main antioxidase in Shaan 253 , Xinong 1043 is SOD ,especially at filling stage.3. Four mutations strains from Shaan 253, eight mutations strains from Xinong 1043 were obtained by Space treatment . There is: lower height mutations are SP-253-38, SP-253-54 , SP-1043-1 , SP-1043-15 , SP-1043-16 , SP-1043-19 , SP-1043-40 , SP-1043-41 ; higher mutations are SP-253-27 , SP-1043-37 ; earlier ripe mutation is SP-253-51 ; lower height and bigger spike is SP-1043-14 .4. The above ground biomass of SP-1043-14 compared with control raise 29.5% by space environment theatment ; the weight of grains per spike in SP-1043-15 compared with control increased 30.8%,the above ground biomass raise 25.8%;the weight of grains per spike in SP-253-38 compared with control reduce 35.5% ,the above ground biomass increased 35.8% ; the weight of grains per spike in SP-1043-19 compared with control reduce 29.7%,the above ground biomass reduce 26.2% . These new strains were different from control on yeild characteristics , which can give valuable materials for breeding studies .