大豆回交群体耐旱耐盐的选择牵连效应及响应分析

利用回交群体和多位点扫描分析方法研究了逆境胁迫下的选择牵连效应,找到相应的基因组区段,并分析了这些区段对不同选择条件的响应。结果如下：随机群体标记偏分离率为34.38%（P〈0.000 1）,经耐旱、耐盐选择后标记偏分离率分别扩大到51.56%和55.88%。说明经过耐旱、耐盐选择后回交导入系群体等位基因偏分离更为严重,群体基因型结构发生变化,表明选择牵连效应的存在。基于牵连效应的选择响应,根据供体等位基因导入频率在耐旱、耐盐选择群体与随机群体中的表现,经卡方分析在0.000 1水平下检测到3个耐旱相关位点（Satt338、Satt640和Sat_108）,5个耐盐相关位点（Sat_271、Satt726、Satt640、Satt513和Sat_108）。

Hitchhiking effect and responses analysis about drought tolerance and salt tolerance of the backcrossing introgression lines in soybean

In this study,the hitchhiking effects in a backcross population with strong selection under salty and drought conditions were analyzed by scanning multiple molecular loci,and 34.38% of the loci were found with segregation distortion in random population.After drought and salt tolerance selection,the segregation distortion ratio increased to 51.56% and 55.88%.SSR alleles showed a serious distortion and genotype structure in backcross introgression lines changed considerably after drought or salt tolerance selection.Three putative drought-tolerance related loci（Satt338,Satt640 and Sat_108） and five putative salt-tolerance loci（Sat_271,Satt726,Satt640,Satt513 and Sat_108） were obtained with chi-square test（P0.000 1） based on hitchhiking effect calculated by comparison of the introgressive frequency of alleles between random population and selected population.