Aug 2026· Frontiers in Plant Science· Vol 17· 0 citations· 94 references
Medicine
TL;DR
This cluster-based framework provides a practical roadmap for consolidating Yr/QYr loci, prioritizing novel genomic targets, and deploying resistance strategically against evolving pathogen populations.
Abstract
Wheat stripe/yellow rust, caused by Puccinia striiformis f. sp. tritici (Pst), remains one of the most significant constraints to global wheat production. Genetic resistance breeding is the most effective, economical, and environmentally sustainable strategy for controlling stripe rust. Over the past two decades, advances in genome sequencing, molecular markers and high-throughput genotyping have led to the reporting of numerous Yr genes and an even greater number of quantitative trait loci (QTL, QYr). Alignment of QYr onto a common refence map is therefore required to consolidate dispersed reports, identify regions of co-localization, and define stable genomic regions underlying stripe rust resistance. In this review, catalogued Yr genes and published stripe rust QTL were systematically compiled from 142 studies and, where sufficient marker information was available, physically re-anchored to the IWGSC RefSeq v2.1 wheat reference genome. This integrative approach enabled consolidation of overlapping loci and delineation of 42 QTL-rich clusters (QRCs). The B-sub genome had the highest number of clusters (20), followed by the A-sub genome (16). The D-sub genome had the least number of clusters (6), with two chromosomes, 5D and 6D, lacking any clusters. Thirteen cloned Yr genes were mapped within these clusters, thereby providing functional validation of QRCs as biologically meaningful reservoirs of resistance. This cluster-based framework provides a practical roadmap for consolidating Yr/QYr loci, prioritizing novel genomic targets, and deploying resistance strategically against evolving pathogen populations.
Integrating high-throughput phenotyping with multiple complementary GWAS models reduces method-dependent bias and enables reliable identification of novel loci and elite germplasm for durable yellow and leaf rust resistance in wheat. The causal agents of yellow and leaf rust in wheat, Puccinia striiformis f. sp. tritici and Puccinia triticina, pose a serious threat to grain yield and quality worldwide. Growing durable resistant wheat cultivars is an effective protection measure contributing to sustainable agriculture. Many of the known resistance genes, however, have been overcome due to the high genetic diversity and adaptability of pathogen populations. Therefore, the present study aimed to identify novel loci associated with yellow rust and leaf rust in a genome-wide association study using 1984 spring wheat accessions from the German Federal ex situ Genebank. Phenotypic data obtained from a detached-leaf assay were combined with 90,283 genotyping-by-sequencing genome-wide markers. Six significant peak marker-trait associations were identified for yellow rust and leaf rust, respectively. These are located on chromosomes 1D, 2B, 3B, 4A, 4B, 4D, 5A, 6B, and 7D. Six candidate genes were identified close to the identified loci. These findings may be valuable for identifying and deploying genetic resources to broaden the genetic basis of resistance and safeguard durability of resistance against yellow and leaf rust.
Behnaz Soleimani, Anne-Kathrin Pfrieme, Ulrike Beukert et al.· Theoretical and Applied Gene...· 0 citations
Key message A non-durable adult plant stripe rust resistance gene in wheat was mapped to the distal region of chromosome 2DS and designated Yr88. Wheat stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most damaging fungal pathogens of wheat globally. Efforts to breed improved wheat cultivars have placed high priority on incorporating resistance to Pst. The resistances used are expressed at either all growth stages (all stage resistance; ASR) or at post-seedling growth stages (aka adult plant resistance; APR). Although APR has a reputation for being more durable than ASR examples have been documented of virulence for this type of resistance in the UK, Europe and in North America. Incursions of two genetically and pathogenically distinct pathotypes of Pst into Australia in 2017 and 2018 changed adult plant field stripe rust responses of many wheat cultivars grown in eastern Australia at that time. In some cases, changes in response could not be accounted for based on virulence on ASR genes, suggesting that the protective value of APR may have changed. This study reports the discovery of a new gene conferring race-specific APR to Pst pathotype 198 E16 A- J+ T+ 17+, a member of the internationally accepted multi-locus genotype (MLG) PstS13. The gene was mapped to the distal region of chromosome 2DS and designated Yr88. Evidence is provided for the presence of Yr88 in near isogenic genes carrying selected ASR and APR Yr genes, four Australian wheat cultivars (LRPB Hellfire, Sherriff CL Plus, Vixen, Wyalkatchem) plus the Mexican green revolution wheat cultivar Lerma Rojo 64 and the Pakistani wheat cultivar Moomal 2000.
R. Park, M. Chhetri, K. Sandhu et al.· Theoretical and Applied Gene...· 0 citations
A new approach to identify environment-specific quantitative trait loci (QTL) using GWAS and the validated resistance gene Yr27 was identified as sole candidate gene for one QTL region of particular relevance for Central European wheat.
Jiao-Jiao Wang, Renate H. Schmidt, Guoliang Li et al.· Theoretical and Applied Gene...· 1 citation
Leaf rust (LR), caused by Puccinia triticina, is a major constraint to global wheat production. Identifying quantitative trait loci (QTLs), conferring adult-plant resistance (APR), and developing breeder-friendly markers are essential for durable disease control. In this study, a recombinant inbred line (RIL) population derived from Liang66-S × Hengmai28 was evaluated for leaf rust severity across four environments. Maximum disease severity (MDS) showed continuous variation and moderate to high correlations among environments, indicating polygenic inheritance. Five APR QTLs were mapped on chromosomes 2BL, 3BS, 3BL, 7BL and 7DL, explaining 4.5–9.8% of the phenotypic variance (PVE) with LOD scores of 2.9–7.9. Among these, QLr.DFI-2BL, QLr.DFI-3BS, and QLr.DFI-7BL correspond to previously reported APR loci, whereas QLr.DFI-3BL and QLr.DFI-7DL represent potentially novel loci. QLr.DFI-3BL was detected across all four environments, while QLr.DFI-3BS and QLr.DFI-7BL showed the highest R2 (7.7–8.5% and 8.4–9.8%). Multiple defense-related genes within the QTL intervals for LR were identified, including the putative NBS-LRR, the putative BTB/POZ-MATH, F-box, receptor-like kinase, polyphenol oxidase, calcium-dependent protein kinase, peroxidase, and ethylene-responsive transcription factors. Based on the flanking markers, five KASP markers were developed. K-LR-3BS (for QLr.DFI-3BS) and K-LR-7BL (for QLr.DFI-7BL) successfully genotyped a natural population with 120 accessions, with call rates of 100% and 94.2%, and showed significant association with reduced leaf rust severity. However, further validation in diverse genetic backgrounds and populations is required before they can be considered for routine marker-assisted selection. These results provide two KASP markers as promising markers that require further validation in diverse backgrounds and highlight QLr.DFI-3BS and QLr.DFI-7BL as promising targets for fine mapping and eventual cloning of APR genes in wheat.
