Plant Genome. 2019 Mar;12(1). doi: 10.3835/plantgenome2018.08.0055.
The appearance of highly virulent and more aggressive races of f. sp. () during the last two decades has led to stripe rust epidemics worldwide and to the rapid erosion of effective resistance genes. In this study, we mapped an adult-plant resistance locus from the Argentinean wheat ( L.) cultivar Klein Chajá, which is effective against these new races. By using wheat exome capture data and a large population of 2480 segregating plants (4960 gametes), we mapped within a 0.24-cM region [332 kb in International Wheat Genome Sequencing Consortium (IWGSC) RefSeq version 1.0] on chromosome arm 1BL. This region overlaps with current maps of the adult-plant resistance gene , which has remained effective for more than 60 yr. An allelism test failed to find recombination between and and yielded similar resistance phenotypes for the two loci. These results, together with similar haplotypes in the candidate region, suggested that and might represent the same gene. However, we cannot rule out the possibility of tightly linked but different genes because most of the 13 genes in the candidate region are annotated with functions associated with disease resistance. To evaluate their potential as candidate genes, we characterized their polymorphisms between resistant and susceptible haplotypes. Finally, we used these polymorphisms to develop high-throughput markers to accelerate the deployment of these resistance loci in wheat breeding programs.
在过去的二十年中，高毒性和侵袭性更强的 f. sp. () 菌株的出现导致了全球条锈病的流行，并迅速侵蚀了有效的抗性基因。在本研究中，我们从阿根廷小麦（ L.）品种 Klein Chajá 中定位了一个成株期抗性基因，该基因对这些新菌株有效。利用小麦外显子捕获数据和一个包含 2480 个分离植物（4960 个配子）的大群体，我们将其定位在 1BL 染色体臂上的 0.24-cM 区域内[332 kb 在国际小麦基因组测序联盟（IWGSC）RefSeq 版本 1.0 中]。该区域与成株期抗性基因的现有图谱重叠，该基因已经有效超过 60 年。等位基因测试未能在和之间发现重组，并且两个基因座的抗性表型相似。这些结果，加上候选区域中相似的单倍型，表明和可能代表同一个基因。然而，我们不能排除紧密连锁但不同基因的可能性，因为候选区域中的 13 个基因大多数都被注释为与疾病抗性相关的功能。为了评估它们作为候选基因的潜力，我们对抗性和敏感单倍型之间的多态性进行了表征。最后，我们利用这些多态性开发了高通量标记，以加速这些抗性基因座在小麦育种计划中的应用。
