番茄黄化曲叶病毒病抗性基因Ty-3a分子标记的筛选及定位

Molecular Mapping and Identifying PCR-based Markers Conferring Ty-3a,A Resistant Gene to Tomato Yellow Leaf Curl Virus

本研究利用番茄黄化曲叶病毒病高感染株系7969-19-1-1-3及其高抗番茄黄化曲叶病毒病的株系Z3(Ty-3a)构建了包含1 404个单株的F2分离群体,并利用分子标记技术对其进行了分析。研究结果显示,在348对SSR、CAPS、SNP、Indel以及RFLP引物中,在双亲间有68对引物扩增出多态性差异,利用获得的68对引物对抗感池进行筛选,获得了7对多态性的标记C2_At3g56230、X38、H5、C4、TGS2216、X1和H12。为了进一步缩小区间,利用F2群体的1 404个单株进行连锁分析。在C2_At3g56230-H12区间寻找新的标记,最后将Ty-3a定位于标记TGS12660和TY3a-P19之间,2个标记的之间的物理距离约为29.7 kb,遗传距离约为0.3 c M。研究结果可为进一步克隆Ty-3a基因和分子标记辅助选择培养抗番茄黄化曲叶病毒番茄新品种奠定基础。

A F2 population, with 1 404 individuals, of 7969-19-1-1-3/Z3 was constructed for molecular mapping the tomato yellow leaf curl virus resistant gene Ty-3a in tomato, and molecular marker analysis was carried out in this study. 348 pairs SSR, CAPS, SNP, Indel and RFLP primers were used to detect polymorphism between the two parents, 68 of them showed polymorphic bands between 7969-19-1-1-3 and Z3, and 7 markers（C2_At3g56230, X38, H5, C4, TGS2216, X1 and H12） were obtained which showed specific DNA bands in the Preferred Small Group. Linkage analysis was performed using F2 population. The Ty-3a gene was ultimately mapped into region of 29.7 kb flanked by the markers TGS12660 and TY3a-P19 on chromosome 6. The genetic distance of this region is about 0.3 c M. The results laid a foundation for further cloning of Ty-3a gene and marker-assisted selection.