Research Of Mutagenic Effects In Three Kinds Of Halophytes Seed Irradiated By Carbon Ion Beam And Electron Beam

In this research, we discussed the sensitivity and optimum irradiation dose of 3 species of halophytes which were irradiated by the carbon ion beam and the electron beam. Dry seeds of three types were irradiated by different parameters of carbon ion beam and the electron beam. This research was investigated the effects of germination and seedling growth of three halophytes irradiated by carbon ion beam and the electron beam to provid theoretical basis for halophytes superior breed.The main conclusion of this research as followed:1. The results indicated that after the carbon ion beam irradiation treatment, germination rate of Salicornia europaea L. slightly increased with the increase of irradiation doses, while survival rate significantly reduced with the increased doses. From the result of germination rate and survival rate of Salicornia europaea L., the irradiation effect of carbon ion beam was not obvious with different energy and different dose rates in low irradiation doses. Remarkable difference could be seen that when the irradiation dose was more than 160 Gy, the greater the dose rate was, the promoting function of germination rate and the inhibition of seedling survival rate were more obviously. LET effect of seed germination rate and survival rate showed remarkable difference, but there was no obvious regularity. The seedling survival rate, germination rate and germination index of Atri Plex aucheri Moq.were reduced with the increase of irradiation doses, while the seed vigor index and seedling length were increased firstly and then reduced. In addition to the 50 kev/u LET and 240 Gy dose, the seedling fresh weight was slightly lowered than the control and others were significantly higher than it. The seed germination rate, germination index, vigor index and seedling height of Atri Plex aucheri Moq.were inhibited significantly by the increased LET and doses. The promoting function of high LET to the seedling fresh weight was significantly superior to the low LET. The germination rate and germination index of Suaeda salsa L.increased slightly, and seedling height rised firstly and then reduced with the increase of irradiation doses. The curve of seedlings fresh and dry weight was like saddle–shaped. Vigor index, seedling root length, and survival rate were significantly reduced with the increase of irradiation doses. The content of MDA and H2O2, the activities of CAT, POD and SOD were increased firstly and then reduced with the increased doses.2. The experiment results showed that after the electron beam irradiation treatment, there was no obvious difference on germination rate of Salicornia europaea L. in every irradiation dose. The germination capacity and germination index of Salicornia europaea L. decreased slightly with the increase of irradiation doses. The germination rate, germination capacity and germination index of Suaeda salsa L.and Atri Plex aucheri Moq.were dropped significantly with the increase of irradiation doses. The seedling fresh weight of Salicornia europaea L. reduced gradually, and the others,seedling fresh weight increased firstly and then reduced with the increase irradiation doses. The vigor index, seedling height and survival rate of three kinds of halophytes were reduced with the increase of irradiation doses.3. The relevant results showed that three halophytes were different sensitive to the carbon ion beam and electron beam radiation. And the same plant also showed different sensitive to different irradiation parameters of carbon ion beam. At last we confirmed the LD50 and optimum irradiation condition: Salicornia europaea L.was irradiated by 30 kev/u carbon ions with 30 Gy/min does rate, and the medial lethal dose was 176 Gy and the optimum irradiation dosage was 140~211 Gy. Suaeda salsa L. was irradiated by 30 kev/u carbon ions with 30 Gy/min does rate, and the medial lethal dose was 364 Gy and the optimum irradiation dosage was 291~437 Gy. Atri Plex aucheri Moq. was irradiated by 75 kev/u carbon ions with 30 Gy/min does rate, and the medial lethal dose was 53 Gy and the optimum irradiation dosage was 42~64 Gy. After the treatment of electron beam irradiation, the medial lethal dose of Salicornia europaea L. was 2929 Gy and the optimum irradiation dosage was 2343~3514 Gy. The medial lethal dose of Atri Plex aucheri Moq.was 219 Gy and the optimum irradiation dosage was 175~263 Gy. The medial lethal dose of Suaeda salsa L. was 2868 Gy and the optimum irradiation dosage was 2294~3441 Gy.