Effects On Physiological And Biochemical Characters Of Three Kinds Of Flax Treated With Physical And Chemical Mutagensis

The purpose of this paper was to search the effect on physiological and biochemical characters of three kinds of flax treated with physical and chemical mutagensis. Arm was to screening optimum mutagen and its concentrations, in order to build the technical base and offer early foundation for flax breeding. First, Germinated seeds of'shuangya No.5','Fany'and'y5z-093'were treated with different concentrations of EMS(ethylme thane sulphonate), NaN3 andγ-ray radialization and combined treatments, then the physiological and biochemical indexes of M1 generation were mensurated, effects on physiological and biochemical index of three kinds of flaxes, which treated with physical and chemical mutagens, were determined. Besides, seedlings of M2 generation were stressed with different concentration of salt, then contents of malondialdehyde(MDA) of the seedling were measured, these layed the prophase foundation for screening salt-resistant flaxes. The main results were as follows:1.There were extremely remarkable negetive correlation with different doses of mutagen on the germination tendency and germination rate of three kinds of flax. Effect of mutation on germination tendency was bigger than that on germination rate, the germination tendency and germination rate of three kinds of flax were all over 50%. The relative root vigour and height of seedling were extremely decreased with increasing does of mutagen, and among the total ,the degressive range of'y5z-093'was the lowest, the range of 'Shuangya No.5' and'Fany'were not significant.2.The contents of chlorophyll of M1 generation of three kingds of flax were all decreased with increasing the dose of mutagens; the contents of osmotic regulation substances(such as free proline ,soluble protien and sugar) of cell were increased at the beginning and then decreased, the content of free proline was fewer and had little change; the change trends of content of soluble protien and sugar were same mainly, the trends were higher than that of controls; The changs of activity of three protective enzymes were complicated, the fluctuation level of SOD were the greatest in three protective enzymes, the change was significant, the fluctuation level of POD were less than that of SOD. The results showed that SOD and POD were main protective enzymes; The contents of MDA were increased with increasing the dose of mutagens, in a word, ascending range of MDA in'y5z-093'seedling was the largest, the range of MDA in 'Shuangya No.5' seedling was the smallest; The fluctuation levels of PAL activity of three flax species were 'Shuangya No.5'>'y5z-093'>'Fany'.in order from high to low.3.There were polymorphism in EST and POD isozyme zymogram bands of the three flax species treated with mutagen and before, the chang of zymogram bands of'y5z-093'was the largest.4.There were different sensitivities on three flax species to different mutagens,'y5z-093'was most sensitive to the radiation of 60co-γray, the effect of mutation was the most serious in three flax species, especially in height;'Fany'was more sensitive to the EMS treatment than other mutagens; 'Shuangya No.5' was more sensitive to NaN3 treatment than other mutagens. In a word, the tolerance of three flax species from high to low, the order was as followed: 'Shuangya No.5'>'Fany'>'y5z-093'. On the whole, effect of combined treatments were higher than that of single treatments, the optimum treatment was EMS(0.1% )+γ-ray radialization(500Gy)or NaN3(0.5×10-3)+γ-ray radialization(500Gy). The dose ofγ-ray radialization was 500Gy which was cirtical value.5.MDA contents of M2 seedling were risen treated with salt stress, there was a positive relation between MDA contents and mutagenic concentration on M1. The content of MDA increased significantly when the NaCl content beyond 100mmol/L; then rise of MDA concents on M2 was not significant treated with low concentration of salt.