长穗偃麦草1St小片段抗条锈病新基因挖掘与转移利用

条锈病是危害我国小麦安全生产的主要病害之一。十倍体长穗偃麦草是进行小麦遗传改良的宝贵基因库，挖掘和利用其中的抗病基因是防控条锈病的有效途径。本项目组前期选育了高抗条锈病、多花多实的小麦-长穗偃麦草小片段易位系SN52684，发现其条锈病抗性位于1St小片段，受新的显性单基因控制。.本研究旨在：（1）分析长穗偃麦草1St小片段的传递规律，阐明其在不同背景下对小麦条锈病抗性和多花多实等主要农艺性状的遗传效应；（2）参考中国春和二倍体长穗偃麦草基因组序列，通过比较基因组学、转录组学分析及表型鉴定，阐明1St小片段内潜在的抗病基因集，根据这些基因在病菌诱导下的表达模式及其在抗病调控网络中的作用，筛选抗条锈病候选基因，并进行功能验证；（3）开发1St小片段的特异分子标记，创制抗条锈病、综合性状优良的新种质。研究结果不仅可为小麦遗传改良提供新的基因资源，还可为有效挖掘和充分利用外源优异基因提供新思路。

Stripe rust is one of the most destructive diseases in wheat. Thinopyrum ponticum carries many useful genes and thus serves as a valuable gene pool in wheat genetic improvement. Development and utilization of disease-resistant genes from this wild relative is an economical and effective strategy to control stripe rust. In our lab, a translocation line SN52684 with small alien segments, exhibiting high resistance to stripe rust and more florets and kernels than its common wheat parent Yannong15, was selected from progenies of wheat-Thinopyrum ponticum. Further studies showed that the stripe rust resistance was controlled by a novel dominant gene located on the small 1St chromosome segment. In order to develop and utilize the new resistance gene, several crosses were made to analyze the hereditary transmission of the alien segment and to illuminate its genetic effects on stripe rust resistance and main agronomic traits under different backgrounds. Taking the genome sequence of Chinese Spring and Th. elongatum as reference, the potential resistance gene sets on the alien chromosome segment will be detected by means of combined identification with comparative genomics, transcriptomics and phenetics. Candidate genes will be identified based on the expression patterns and genetic network of these genes under pathogen infection, and then the function of candidate genes is to be verified. Furthermore, molecular markers specific to the alien segment will be designed and used as assistants to breed new germplasms with high resistance to stipe rust and positive agronomic traits. The results of this project can provide not only novel gene resources for wheat genetic improvement, but also new strategy for effectively developing and utilizing alien useful genes.