| Potato(Solanum tuberosum L.)occupies an important position in industrial and agricultural production,but potato cultivars are vulnerable to the threat of low temperature and frost,so it is of great significance to effectively utilize the cold-resistant resources in wild species.Somatic cell hybridization can transfer the excellent traits of wild species to cultivated species.In order to use somatic hybrids to create resources and explore their genetic rules,this study uses somatic hybrids obtained in our laboratory previously were used as the research material to systematically evaluate somatic hybrids.The cold resistance,ploidy and agronomic traits of cell hybrids.And backcrossing with cultivated species created cold-resistant resources with the blood of wild species S.malmeanum.The main research results are as follows:1.There were 25 hexaploid lines,6 aneuploid lines,6 pentaploid lines,4 tetraploid lines and 2 heptapeloid lines identified of 44 individual cell hybrid lines(S.tuberosum cv.AC142+S.malmean acc.MLM266-2).Then the statistics of agronomic traits and the identification of cold resistance showed that 41 of them were growing well,and most of the agronomic traits varied widely.The direct cold resistance ability of somatic hybrids ranges from-3.56°C to-1.97°C,39 of which are distributed between the cultivated hybrid parent AC142(-2.38°C)and the wild hybrid parent MLM266-2(-5.1°C)Among them,5were higher than the cultivar fusion parent AC142;the domestication ability of somatic hybrids was between 0.15℃ and 4.19℃,of which 8 were lower than AC142(0.74℃),and 1 was higher than MLM266-2(2.97℃)),32 copies were distributed between the two fusion parents,accounting for 72.73% of the total.Combining the results of agronomic traits and cold tolerance identification,Selection of M+A2-1,M+A17-1,M+A18-1 and other 9-cell hybrids and cultivars with strong cold resistance and excellent agronomic traits have constructed 44 backcross combinations.The hybridization efficiency analysis found that Among the cell hybrids,M+A18-1 and M+A59-1 have higher hybridization ability as the female parent,and the success rates are 69.81% and 58.73% respectively.At the same time,it was found that Huashu 1 and Huashu 11 had relatively high hybridization ability as male parent.The high hybridization efficiency provides the material basis for the creation of potato resources.2.In order to further explore the cold resistance and agronomic traits of the backcross offspring,the three combinations of FT069,FT070 and FT071 in the BC1 generation were further studied.The ploidy identification of BC1 showed that the ploidy distribution range of the offspring of FT069 combination is wide,including tetraploid,pentaploid,hexaploid,and aneuploid.The largest number was pentaploid,accounting for31.58%;FT070 The combination includes 3 tetraploid,7 pentaploid,5 hexaploid and 8aneuploid;FT071 combination is mostly aneuploid,accounting for 50%,including 1tetraploid,6 pentaploid and 6 hexaploid.Then the three BC1 generation combinations were analyzed for agronomic traits and cold resistance identification.The results showed that the BC1 generation had segregation of traits in plant shape,flower color,anther,potato color,etc.Overall,the plant height increased,and the shape,The yield has been improved to a certain extent,but the habit of forming potatoes needs further improvement.In terms of cold resistance,the progeny of the three backcross combinations showed obvious resistance to susceptibility.After treatment at-3°C,15 of the 40 materials of the FT069 combination had a lower relative conductivity than the parent M+A17-1,7 The relative conductivity of FT070 is higher than that of the male parent Redsen;the relative conductivity of 5 of the 19 materials of FT070 is lower than that of the female parent M+A17-1,and the relative conductivity of 5 is higher than that of the male parent Adirondack;6 of the 26 materials of FT071 are relative The conductivity is lower than the female parent M+A2-1,and 5 copies are higher than the male parent 393160-4.In terms of domestication resistance,as a whole,the cold resistance of the three combinations after domestication has been strengthened to a certain extent,and the isolation of resistance is more obvious.According to the results of agronomic traits and cold resistance identification,a total of 6 excellent individual plants,FT069-32,FT070-1,FT070-23,FT071-21,FT071-22,and FT071-40,were backcrossed to construct BC2 and analyzed backcross Relevant data found that the cultivated variety Huashu 1 as the male parent and the BC1 generation had a high pollination success rate.3.The offspring of the three combinations FT070-23×Huashu No.1,FT071-22×Huaen No.1,and FT071-22×Huashu No.13 were named FT120,FT121,and FT122,respectively.The cold resistance of the BC2 generation was identified.The results showed that the cold resistance of the BC2 generation was separated.In the FT120 combination,4 materials had stronger cold resistance than the female parent FT070-23,and 12 materials were between the two parents.The material is lower than the male parent Huashu No.1;1 material in the FT121 combination has stronger cold resistance than the female parent FT071-22,and 5 materials are lower than the male parent Huaen 1;8materials in the FT122 combination have strong cold resistance In the female parent FT071-22,32 materials were less than the male parent Huashu No.13,and the other 9materials were between the two parents.Subsequent investigations on agronomic traits of materials with outstanding resistance should be conducted to screen out breeding materials with excellent comprehensive traits. |
PDF Full Text Request