Biological Effects Of ～(60)Co-γ Ray On Cucumis Melo L.ssp.melo

In order to investigate the changes of different cultivars seeds treated with different dosages of ⁶⁰Co-γrays. Firstly, references in mutation breeding were gathered, and then analyzed the mutation effects and actions in breeding, at last, summarized advantages and disadvantages of various mutation methods, especially, effects of ⁶⁰Co-γrays in melon breeding. There is few all-round research on melon irradiation breeding through the method is applied commonly in melon breeding and some valuable cultivars had been breeded recently. Therefore, determined seeds germination, shape indexes, quantity of seedling growth, physiological-biochemical indexes (SOD activitiy, POD activitiy, MDA content) of Huanghou and Jiashigua F1 which had been treated with OGy, 300Gy, 450Gy, 600Gy, 750Gy, 900Gy, 1050Gy dosages of ⁶⁰Co-γrays, the results showed that the effect was similar when different cultivars was treated with same dosages of ⁶⁰Co-γrays, but the effect was distinct when same cultivars was treated with different dosages of ⁶⁰Co-γrays.OGy, 300Gy, 450Gy, 600Gy, 750Gy dosages of ⁶⁰Co-γrays were selected to irradiate Jiashigua, Huanghou, Jiashigua F1 and Jinlong seeds through the effect of different dosages of ⁶⁰Co-γrays to different cultivars was analyzed, and then Ml were breeded in Tulufan, M2 were breeded in Sanya. Characters of All mutations in growth were writed down and identified qualities of theirs fruit through determined weight of single fruit, index of fruit, thickness of fruit peel and flesh, diameter seed's cavity and content of center total soluble solid, the results showed that: 1, there were different mutations in four cultivars' Ml which was treated with different dosages and the effects were similar in Ml and M2 that the cultivars' MO were treated with same dosages, furthermore the changes which occurred in Ml were distinct in M2. 2, The effect was different that different cultivars were treated with same dosages. There were some mutations in Ml and M2 growth, but no mutation in fruit of Ml. Some high quality fruits in M2 were gotten to serve as breeding resource with better flavor, abundant content of center total soluble solid, characters of surface different with their parents, which suggested that there were mutations in M2, further analysis found that theirs MO had been treated with high dosages of ⁶⁰Co-γrays. There is a belief that mutation needs seeds treated with higher dosages rays. The research provides the references for mutation breeding on melon treated with ⁶⁰Co-γrays and selections of right dosages, accumulates the data for mutation breeding treated with ⁶⁰Co-γrays on Cucumis melo.