Ballvora A, Hesselbach J, Niewöhner J, Leister D, Salamini F, Gebhardt C
Max-Planck-Institut für Züchtungsforschung, Köln, Germany.
Mol Gen Genet. 1995 Nov 1;249(1):82-90. doi: 10.1007/BF00290239.
The dominant allele Gro1 confers on potato resistance to the root cyst nematode Globodera rostochiensis. The Gro1 locus has been mapped to chromosome VII on the genetic map of potato, using RFLP markers. This makes possible the cloning of Gro1 based on its map position. As part of this strategy we have constructed a high-resolution genetic map of the chromosome segment surrounding Gro1, based on RFLP, RAPD and AFLP markers. RAPD and AFLP markers closely linked to Gro1 were selected by bulked segregant analysis and mapped relative to the Gro1 locus in a segregating population of 1105 plants. Three RFLP and one RAPD marker were found to be inseparable from the Gro1 locus. Two AFLP markers were identified that flanked Gro1 at genetic distances of 0.6 cM and 0.8 cM, respectively. A genetic distance of 1 cM in the Gro1 region corresponds to a physical distance of ca. 100 kb as estimated by long-range restriction analysis. Marker-assisted selection for nematode resistance was accomplished in the course of constructing the high-resolution map. Plants carrying the resistance allele Gro1 could be distinguished from susceptible plants by marker assays based on the polymerase chain reaction (PCR).
显性等位基因Gro1使马铃薯对根结线虫罗氏马铃薯胞囊线虫具有抗性。利用RFLP标记，已将Gro1基因座定位到马铃薯遗传图谱的第七条染色体上。这使得基于其图谱位置克隆Gro1成为可能。作为该策略的一部分，我们基于RFLP、RAPD和AFLP标记构建了围绕Gro1的染色体片段的高分辨率遗传图谱。通过混合分组分析法选择与Gro1紧密连锁的RAPD和AFLP标记，并在1105株植物的分离群体中相对于Gro1基因座进行定位。发现三个RFLP标记和一个RAPD标记与Gro1基因座不可分离。鉴定出两个AFLP标记，分别在遗传距离0.6 cM和0.8 cM处位于Gro1两侧。根据长距离限制分析估计，Gro1区域1 cM的遗传距离对应于约100 kb的物理距离。在构建高分辨率图谱的过程中完成了对线虫抗性的标记辅助选择。携带抗性等位基因Gro1的植株可以通过基于聚合酶链反应（PCR）的标记分析与感病植株区分开来。
