*Article* **Physical Location of New Stripe Rust Resistance Gene(s) and PCR-Based Markers on Rye (***Secale cereale* **L.) Chromosome 5 Using 5R Dissection Lines**

### **Wei Xi 1,2,3,**†**, Zongxiang Tang 1,2,3,**†**, Jie Luo 1,2,3 and Shulan Fu 1,3,\***


Received: 8 July 2019; Accepted: 26 August 2019; Published: 30 August 2019

**Abstract:** The rye (*Secale cereale* L.) 5R chromosome contains some elite genes that can be used to improve wheat cultivars. In this study, a set of 5RKu dissection lines was obtained, and 111 new PCR-based and 5RKu-specific markers were developed using the specific length amplified fragment sequencing (SLAF-seq) method. The 111 markers were combined with the 52 5RKu-specific markers previously reported, and 65 *S. cereale* Lo7 scaffolds were physically mapped to six regions of the 5RKu chromosome using the 5RKu dissection lines. Additionally, the 5RLKu arm carried stripe rust resistance gene(s) and it was located to the region L2, the same region where 22 5RKu-specific markers and 11 *S. cereale* Lo7 scaffolds were mapped. The stripe rust resistance gene(s) located in the 5RLKu arm might be new one(s) because its source and location are different from the previously reported ones, and it enriches the resistance source of stripe rust for wheat breeding programs. The markers and the *S. cereale* Lo7 scaffolds that were mapped to the six regions of the 5RKu chromosome can facilitate the utilization of elite genes on the 5R chromosome in the improvement of wheat cultivars.

**Keywords:** wheat; rye; 5R dissection line; PCR-based markers; physical map; stripe rust
