Construction Of SRAP Genetic Map And The QTL Analysis Of Chinese Cabbage Resistance (Ecc-1-1)

A F2 population with 225 individual plants crossed by female parent(A32-2) and male parent(A 19-2) were used to construct the molecular genetic map using SRAP molecular marker. At the same time,carried out QTL orientation of Chinese Cabbage resistance to Ecc-1-1 and established the Soft Rot resistance molecule basis for Building-up the resistance breeding molecule mark assists system choosing of Chinese cabbage Soft Rot.The main results are summarized as the followings:1.The test used the method of fast identify method.The results indicated that the difference of two parents resistance and susception was obvious,the female parent A32-2 showed resistant disease,male parent A19-2 showed sensitive and F1 showed resistant.According to the disease grand and plant numbers made the two-dimensional picture and used SAS8.2 univariate to examine the skewness and kurtosis.The number of 0 grand was 21 plants,1 grand was 60 plants, 3 grand was 75 plants,5 grand was 43 plants,7 grand was 16 plants,9 grand was 10 plants,the total plants were amount 225.The skewness was 0.8484,and kurtosis was 0.1358,illustrated the diseased-plant numbers was normal distribution,they were according to the character of quantitative character.2.The test optimized the condition of PCR through testing the density grade of Mg²⁺, dNTP,TaqE,primer,and DNA template.The suitable reaction system im 25μl reaction solution contained Mg²⁺3.0mmol/L,dNTP0.3mmol/L,TaqE1.5U,primer0.2μmol/L,60ngDNA.3.A molecular genetic map of Chinese cabbage was constructed by the analysis of 139 SRAP markers,with Mapmaker/EXP3.0b software,a total of 103 markers were mapped to 10 linkage groups,covering 1223.6 cM with an average distance of 11.9 cM between loci.The number of markers in every linkage group varied from 4 to 25,maximum distance was 33.1 cM, while minimal distance was 2.2 cM,the total map distance was from 54.0 to 348.0 cM.4.The molecular marker of F₂ analysed used the MAPMAKER 3.0 to analyse,LOD is 3.0,supplied the max-distance 50cM to divide the linkaged group and arrange the normal distance of markers,and used the WINQTLCart2.5 to make map.The results divided into four linkage-group.The test found seven QTLs cite.QE1 and QE2 located on the secondly linkage population.Its additive effects were 9.17 and 10.56.The explainable phenotype variation were 14.23%and 22.73%;QE3 located on the sixth linkage population.Its additive effects were 5.24.The explainable phenotype variation were 9.33%;QE4 located on the seventh linkage population.Their additive effects were 4.35.The explainable phenotype variation were 8.52%.