Nsabiyera Vallence, Baranwal Deepak, Qureshi Naeela, Kay Pippa, Forrest Kerrie, Valárik Miroslav, Doležel Jaroslav, Hayden Matthew J, Bariana Harbans S, Bansal Urmil K
Faculty of Science, School of Life Sciences and Environment, The University of Sydney Plant Breeding Institute, Cobbitty, NSW, Australia.
Agriculture Victoria Research, AgriBio, Bundoora, VIC, Australia.
Front Plant Sci. 2020 Feb 4;10:1787. doi: 10.3389/fpls.2019.01787. eCollection 2019.
Leaf rust, caused by , threatens global wheat production due to the constant evolution of virulent pathotypes that defeat commercially deployed all stage-resistance (ASR) genes in modern cultivars. Hence, the deployment of combinations of adult plant resistance (APR) and ASR genes in new wheat cultivars is desirable. Adult plant resistance gene was previously mapped on the long arm of chromosome 4B of cultivar VL404 and flanked by microsatellite markers (8.1 cM) and (10.1 cM), neither of which was sufficiently closely linked for efficient marker assisted selection. This study used high-density SNP genotyping and flow sorted chromosome sequencing to fine-map the locus as a starting point to develop a diagnostic marker for use in breeding and to clone this gene. Marker was mapped 0.4 cM proximal to , whereas a group of markers including were placed 0.6 cM distal to this gene. Testing of the linked markers on 75 Australian and 90 European cultivars with diverse genetic backgrounds showed that _ was most strongly associated with . Our results also show that the genomic region contains structural variation relative to the reference stock Chinese Spring, possibly an inverted genomic duplication, which introduces a new set of challenges for the cloning.
叶锈病由……引起，由于致病型不断进化，能战胜现代品种中商业部署的全生育期抗性（ASR）基因，从而威胁全球小麦生产。因此，在新的小麦品种中部署成株抗性（APR）和ASR基因的组合是可取的。成株抗性基因……先前被定位在品种VL404的4B染色体长臂上，两侧分别是微卫星标记……（8.1厘摩）和……（10.1厘摩），但这两个标记都没有紧密到足以用于高效的标记辅助选择。本研究使用高密度SNP基因分型和流式分选染色体测序来精细定位……位点，以此为起点开发用于育种的诊断标记并克隆该基因。标记……被定位在……近端0.4厘摩处，而包括……在内的一组标记位于该基因远端0.6厘摩处。在75个具有不同遗传背景的澳大利亚品种和90个欧洲品种上对连锁标记进行测试表明，……与……关联最为紧密。我们的结果还表明，……基因组区域相对于参考品种中国春存在结构变异，可能是基因组倒位重复，这给……克隆带来了一系列新挑战。
