| In China, potato was an important grain & vegetables crops and industrial raw materials, with the traits of short growth period, high yield, wide adaptability, and nutrient-rich. The development of potato production had an important role in booming economy, increasing farmer's income, and guaranteeing food security. The key factors of industrialization of potato were breeding improved varieties, increasing yield, and improving milling quality, and the foundation of breeding new varieties was germplasm resources. While China was short of potato germplasm resources, and the main varieties of production were largely cultivated between the tetraploid breeding, which had a narrow genetic background. Moreover, as a autotetraploid crop, potato had a high level of cytohet, complex segregation of gene, low frequency of recessive genes, partly pollen sterility, low seed setting percentage of Hybrid, and so on, that slowed the studing progress of wild resources, and restricted the breeding varieties through conventional breeding methods. So inducing potato mutation by the use of exogenous factors and breeding potato materials with excellent characteristics was one of the primary means of creating new germplasm resources, in which mutation breeding was not only an important supplement to conventional breeding, but also an irreplaceable means.Compared with conventional breeding, mutation breeding have many advantages, included convenient operation, high Mutation frequency, unaffected by the gene narrow limits, short breeding period, unique advantages in creating new gene resources or changing a single gene control in the special characters and the traits of mutation offspring quickly stable. Besides, asexual reproduction could be used to fix potato beneficial mutations got by mutagenesis, which had special application value and could enrich potato gene pool resources to some extend and improve breeding level. In this study,60Coγradiation was used for the mutation of potato varieties to discuss of the effects of 60Coγradiation on phenotypic traits and genome DNA of cv. Favorita minituber and seed potato, and EMS was used for the mutation of stems of cv. Favorita plantlet, with axillary buds, to research the influence of EMS on budding, growth of regenerated plants, and genome DNA. The test results are as follows.1. The results of 60Coγradiation treatment(1) Compared with the non-irradiated controls, the whole period of germination was significantly prolonged for cv. Favorita minituberes and seed potatoes treated with 60Co y radiation. The minitubers's germination period was prolonged by 3.6d～38.8d at 10Gy～80Gy, and the seed Potato's germination period was prolonged by 1.3d～27.4d at 10Gy～100Gy.(2) 60Coγradiation resulted in mutation on stem and leaf of potato, especially on leaf, and the aberration rate of minituber and seed potato were 76.1% and 60.5%, respectively. While this mutation only appeared in VM1.(3) The results of minitubers:Low doses of radiation (<40Gy) had an effect of increasing the number of leaves.In the group treated with 10Gy,90d'leaves of VM1 and 30d'leaves of VM2 were significantly increased over the control by 6.5 per plant and 2.2 per plant, respectively.Radiation with 20Gy significantly shorten the growth period of VM1 and VM2 over the control by 3.7d and 4.9d, respectively, the plant height and stem diameter of VM2 were significantly superior to other treatment groups. While, beyond 40Gy treatment could seriously repressed plant growth, included decreasing germination rate, extending germination time, weakening stems'growth.The general trend of effects of irradiation was suppression in VM1, and the main manifestations included decreasing tuberization rate, declining tuber set per plant, and reducing production, though the radation with 10Gy increased the yied per dramatically over the control by 37.2%. Radation with 20Gy and 40Gy's tuber set and yied per plant were better than other treatment.(4) The results of seed potato:The doses of 10Gy and 20Gy had no significantly effect on the growth of VM1. Radation with 10Gy increased the number of tubers per plant significantly. while decreased the yield per plant dramatically over the control (37.6g/plant) by 10.6g/plant. Radition with 20Gy had no significantly effect on tuber formation. Beyond 20 Gy irradiation treatment could inhibit plant growth, reduce branch, weaken stem, and reduce yield per plant over the control(37.6g/plant) by 20.7g/plant～33.1g/plant.(5) 60Coγradiation resulted in a series of morphological variations in minituber and seed potato, and the mutant genes could be detected by moleculat markers. And SRAP analysis showed the polymorphic bands in two forms of flawing bands and increasing bands. The polymorphic bands were mainly concentrated in the range 100bp-500bp.(6) Selected nine polymorphic bands to clone, which induced by 60Coγradation on favorita minitubers, and clearly and steady in the individual and bulk selection results of SRAP, then sequenced five polymorphic bands with better clone effect to retrieve the similarity sequence in Genbank, and found 4 gene segments with identities between 76% and 81%. Sequence 1 and Solanum tuberosum clone RH066A20's identity was 86%. Both sequence 2 and sequence 4 had similarity with Solanum tuberosum resistance gene cluster, and their identities were 76% and 81%, respectively. Sequence 3 and Solanum tuberosum chromosome 5 clone RH072103's identity was 89%. While the sequence 5 and with Solanum lycopersicum cv. Heinz 1706 had 93% identity.2. The results of EMS treatment(1) EMS treatment had a significantly inhibition on bud emergence and rooting stem of Favorita vitro axillary stem, including reduced seedling emergence, lower rooting rate, and reduce the munber of roots.Concentration of 0.5%,2.0%, and 4.0% promoted the growth of leaf and stem of plantlets after transplanted, and their yield were significantly increased over control, in which the highest yield of 4.0% treatment group compared to control (0.3g/plant), the yield was increased by 1.5g/plant.(2) The treatment of EMS did not result in morphological variation, while SRAP analysis showed that DNA aberrations appeared in the test materials.5 out of 26 pair SRAP primers could amplify polymorphism in bulk selection, with 11 bands being polymorphic, in which had 7 increasing bands and 2 flawing bands...
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