小麦持久抗条锈病主效基因YrRC-4BL的精细定位及候选基因分析

小麦条锈病严重影响我国小麦稳产、高产。培育持久稳定的抗病品种是防控条锈病最经济、有效的措施。普通小麦品系P10103对条锈病保持抗性近40年，前期成功在其4BL染色体上定位一个稳定的主效抗病基因YrRC，经条锈菌多小种鉴定发现，YrRC呈现典型的成株期广谱抗性，且抗性效果优于广谱抗病基因Yr18。本项目拟开展YrRC精细定位及其高效利用的工作，包括：1）通过BSR-Seq和重测序技术开发分子标记并结合大规模遗传群体精细定位YrRC，明确功能区段的组成，初步选定候选基因；2）结合紧密连锁标记、候选基因的重要信息及单倍型分析，开发YrRC辅助选择标记，用于该抗源的定向转育及分子聚合育种；3）利用高代近交系分析YrRC在不同遗传背景下抗性效应及其与产量、品质等性状的关系，评估YrRC在小麦改良中的应用价值。研究结果将会极大地促进持久抗病基因YrRC的克隆及其在分子改良育种中的高效利用。

The biotrophic fungal pathogen Puccinia striiformis f. sp. tritici (Pst), the causal agent of stripe rust or yellow rust (YR), is one of the most important diseases threatening wheat production in China. The acceleration of stripe rust resistance is the prior choice for limiting disease epidemics and minimizing the economic losses caused by the disease. Breeding for durable resistance cultivars depends upon the availability of resistance resources. Wheat cultivar P10103 derived from CIMMYT displays high resistance to stripe rust in our fields more than ten years. In our previous study, we have dissected the genetic basis of its high resistance to stripe rust and preliminarily mapped a major QTL, temporarily named YrRC, spanning the interval of more than 7 cM on terminal of chromosome 4BL. The gene YrRC confers broad-spectrum resistance as effective as Yr18 and it has potential utilization value for wheat breeding. The objectives of the present project are: (1) to employ both BSR-Seq and whole genome resequencing approaches to refine the genomic region of YrRC, (2) to identify the candidate genes associated with resistance, (3) to develop robust DNA markers that can be reliably used for marker-assisted selection in wheat breeding programs.