Study On Germinating Character And Enzymatic Activity Of Flue-Cured Tobacco Varieties Under Space-Flight Mutation

The space-flight mutation breeding is one kind of high speed,high-effect mutation breeding method,and it's also an important method of breeding in nowadays. The seed characteristic of five flue-cured tobacco varieties(Xiangyan-1,T61, YZ206,TH-5 and YZ160) under space-flight mutation and SOD,CAT and POD activity of variants in either seedling stage or growing stage are studied in this article. The rule of the germination percentage,germinating energy and the SOD,CAT and POD activity of variants were analysised systematically.The main research results are as follows:1.The germination percentage and germination energy of variants which after space-flight mutation are lower than that of CK notablely,possible reason may be that high altitude strong radiation,high vacuum,tiny gravity and the peculiar unclear factor environment had disadvantageous influence on the seed.The reason of difference of germination percentage and germinating energy among different varieties mainly caused by different genetypes and their adaptability to environment.2.All of mutant plants showed significant higher SOD,POD and CAT activity in seedling stage and field growth stage than that of CK,ie,space-flight could enhance activity ability and stress-resistance of flue-cured tobacco varieties in seedling stage.During field growth stage,the activity of POD,SOD and CAT are rising at first, reaching a peak at flourishing stage,decreasing gradually afterwards.Furthermore,a few of mutant plants shows pretty high POD activity at 45 days after transplanting.