四倍体马铃薯SSR遗传图谱的构建及晚疫病抗性QTL初步定位

利用四倍体马铃薯栽培种‘大西洋'和‘陇薯6号'杂交得到的190个F_1株系为作图群体,构建了四倍体马铃薯的分子遗传图谱,采用区间作图法对马铃薯晚疫病抗性进行了QTL初步定位。结果显示:通过对190个F_1株系进行检测,共发现有7个与晚疫病抗性相关的QTL位点,分别分布在第5、6、7、10和11连锁群上;各位点的LOD值在2.70~10.32之间,其中主效QTL位点3个(LOD≥3.5),可解释17.37%~65.68%的表型变异。获得紧密连锁的特异标记(S183-210、S148-460)为进一步进行QTL精确定位提供了参考。

Construction of a genetic map based on SSR markers and the primary QTLs mapping of the resistance to Phytophthora infestans in tetraploid potato

In this study ,we mapped and characterized quantitative trait loci(QTL) associated with the resistance to Phytophthora infestans in a tetraploid potato variety. A total of 190 F₁ individuals obtained by crossing between foreign cultivar ‘Atlantic’ and local cultivar ‘Longshu No.6’and used to construct the map containing 171 SSR markers. By using interval mapping, 7 QTLs for resistance to P. infestans were identified. These QTLs were mapped on linkage group 5, 6, 7, 10 and 11, respectively. The phenotypic variations explained by each QTL ranged from 17.37% to 65.68%, and their LOD values varied from 2.70 to 10.32. Of the three QTLs with LOD value higher than 3.5 were considered major QTLs. The two tight linkage SSR markers S183-210 and S148-460 would be used in fine mapping of the resistance to P. infestans in tetraploid potato.