Skip to main content
ARS Home » Plains Area » Fargo, North Dakota » Edward T. Schafer Agricultural Research Center » Cereal Crops Improvement Research » Research » Publications at this Location » Publication #417212
Research Project: Improvement of Disease and Pest Resistance in Barley, Durum, Oat, and Wheat Using Genetics and Genomics

Location: Cereal Crops Improvement Research

Title: Genetic and physical localization of a leaf rust susceptibility gene in barley

Author
item LIU, RUIYING - North Dakota State University
item LUO, DANGPING - North Dakota State University
item Scheffler, Brian
item Hulse-Kemp, Amanda
item Overlander-Chen, Megan
item Nandety, Raja Sekhar
item Fiedler, Jason
item Chu, Chenggen
item Zhong, Shaobin
item Yang, Shengming

Submitted to: Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/24/2025
Publication Date: 5/27/2025
Citation: Liu, R., Luo, D., Scheffler, B.E., Hulse-Kemp, A.M., Overlander-Chen, M., Nandety, R., Fiedler, J.D., Chu, C.N., Zhong, S., Yang, S. 2025. Genetic and physical localization of a leaf rust susceptibility gene in barley. Theoretical and Applied Genetics. 138:127. https://doi.org/10.1007/s00122-025-04916-w.
DOI: https://doi.org/10.1007/s00122-025-04916-w

Interpretive Summary: Leaf rust is one of the most devastating diseases of barley. Understanding the genetic mechanisms involved in governing resistance and susceptibility of barley plants to leaf rust would aid researchers in developing barley varieties that better resist the disease. In this study, we conducted genetic analysis of resistant and susceptible barley lines to determine more precisely the genomic location of a specific barley gene that, when present, renders the barley plant susceptible to the disease. This gene, referred to as Sph1, was located to a small segment of a specific barley chromosome. Further analysis of the segment indicated that it harbors two genes coding for protein kinases, which are typically associated with disease resistance or susceptibility in plants. Therefore, the protein kinase genes may be a focus of future research to discover the identity of the Sph1 gene. We also developed molecular markers that can be used to track the presence/absence of the gene when developing new barley varieties. The results of this research provide a foundation for geneticists to advance our knowledge of how barley plants interact with the pathogen that causes leaf rust and provides tools for breeders to develop leaf rust-resistant barley varieties.

Technical Abstract: Caused by the biotrophic fungal pathogen Puccinia hordei, leaf rust is one of the important foliar diseases in barley. Although a few dominant resistance genes to leaf rust have been identified and cloned in barley, resistance conferred by major genes has been frequently defeated by the pathogen. A recessive resistance was identified in a spring barley accession using the VA90-34 isolate which is virulent to most of major resistance genes. To fine-map towards cloning of this recessive resistance (hereafter named Sph1, Susceptibility to P. hordei 1), we conducted genetic mapping with biparental populations in the present study. The Sph1 gene was anchored close to the telomere of the short arm of chromosome 3H, delimited within a 400 kb region. Of the six predicted genes in the Sph1 region, two genes encoding putative receptor-like kinase were selected for functional validation. Therefore, our study provides high-resolution genetic map and candidates of Sph1, paving the foundation for cloning of this important gene.