Wheat Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), poses a significant threat to wheat production globally. Understanding regional virulence patterns is crucial for effective resistance gene deployment and sustainable disease management. A total of 209 Pst isolates were collected from six provinces (Gansu, Qinghai, Shaanxi, Hubei, Henan, and Jiangsu) across two major epidemic regions in 2023-2024. Isolates were tested against 19 Chinese differential hosts and 18 Yr single-gene differentials. Using Chinese differentials, 54 races were identified, with CYR34 (19.62%), CYR32 (10.53%), and CYR33 (9.09%) being predominant; 31 were new. The Yr single-gene differential detected 63 races, VR1 (10.05%), VR2 (6.22%), and VR3 (5.74%) were the most frequent in the VR (Virulence Race) system, where numbers indicate sequential race designations based on distinct virulence patterns. Virulence assessment showed overwhelming prevalence against 17 Chinese varieties and 10 single-gene lines (> 60% frequency), while complete susceptibility absence occurred against Zhong 4 (Yr genes unknown), Triticum spelta Album (Yr5), Avocet S*6/Yr5, and Avocet S*6/Yr15. This study validates the superior discriminatory power of Yr single-gene differentials for Pst race identification and provides essential baseline data for regional resistance breeding programs. The findings support the adoption of enhanced surveillance systems for sustainable stripe rust management in China.

Wheat stripe rust, caused by the Puccinia striiformis f. sp. tritici (Pst), is a devastating disease that threatens global wheat production. Pst deploys numerous effectors to manipulate host processes during infection. Receptor-like cytoplasmic kinases (RLCKs) coordinate complex defense responses against microbial pathogens, but their roles in wheat immunity remain poorly understood. In this study, we identified a wheat TaRLCK176, the ortholog of OsRLCK176, plays a positive role in wheat resistance to Pst. Stable overexpression of TaRLCK176 in wheat confers broad-spectrum resistance against Pst. Additionally, TaRLCK176 is targeted by the stripe rust effector Pst08755, which promotes the degradation of TaRLCK176, thereby suppresses chitin-induced MAP kinase activation, and facilitates Pst infection. In summary, our results reveal that Pst effector Pst08755 targets and promotes the degradation of TaRLCK176, suppressing host immunity. This study provides new insights into the mechanisms of Pst pathogenicity and wheat defense.

Although tubby-like proteins (TLPs) are evolutionarily conserved across eukaryotes, their roles in orchestrating plant immune responses, particularly against obligate biotrophic pathogens, remain poorly defined. In this study, we found that TaTLP5, a member of the tubby-like F-box gene family, is rapidly upregulated following Puccinia striiformis f. sp. tritici (Pst) infection. Silencing TaTLP5 in wheat enhances susceptibility to Pst, whereas its overexpression confers resistance by promoting reactive oxygen species (ROS) accumulation. In addition, the molecular interaction mechanism underlying TaTLP5-mediated wheat disease resistance has been elucidated. The results showed that TaTLP5 forms an SKP1-Cullin1-F-box (SCF)-type E3 ubiquitin ligase complex with TaSKP1 (S-phase kinase-associated protein 1) and TaCullin1. Notably, this complex mediates the ubiquitination and degradation of TaCAT1 (Catalase1), a key susceptibility factor in wheat. This ubiquitination-dependent degradation of TaCAT1 elevates ROS accumulation, thereby enhancing wheat resistance against Pst. Our findings revealed a conserved regulatory module by which the TaTLP5-TaSKP1-TaCullin complex modulates ROS-dependent immunity via ubiquitination-mediated degradation of TaCAT1 during wheat-Pst interactions. These mechanistic insights highlight potential actionable targets for the rational breeding of disease-resistant crop varieties.

As global warming continues, rising temperatures significantly alter the interactions between wheat and the stripe rust pathogen Puccinia striiformis f. sp. tritici (Pst). Utilising high-temperature all-stage (HTAS) resistance to Pst is a novel strategy for breeding climate and disease resilient wheat cultivars. Cysteine-rich receptor-like kinases (CRKs) are involved in massive transduction pathways upon perception of biotic and abiotic stresses in plants. Here, we identify a CRK subfamily gene, TaCRK6, from Xiaoyan 6 (XY6), a wheat cultivar possessing non-race-specific and durable HTAS resistance to stripe rust. The expression of TaCRK6 concurrently responds to both Pst inoculation and the relatively high temperature treatment. Silencing TaCRK6 significantly attenuated HTAS resistance to Pst in XY6. Furthermore, overexpression of TaCRK6 in susceptible wheat cultivar Fielder exhibited a resistant phenotype with reduced Pst sporulation and increased necrosis. TaCRK6 interacts with and primarily phosphorylates the cytoplasmic kinase TaRLCK185 with the threonine residue at position 248. Notably, the MAPK signalling cascades, positioned downstream of TaRLCK185, are proved to participate in activating HTAS resistance in XY6. TaRLCK185 transduces the MAPK cascade signals by interacting with and primarily phosphorylating the serine residue of TaMAPKKK1 at position 132. TaCRK6-mediated phosphorylation of T248 alters the conformation of TaRLCK185, which in turn promotes its interaction with TaMAPKKK1, ultimately leading to activation of the downstream TaMAPKKK1-TaMAPKK9-TaMAPK6 cascade. Moreover, the TaCRK6-TaRLCK185-TaMAPKs module regulates the biosynthesis of salicylic acid (SA). These results indicate a TaCRK6-TaRLCK185-TaMAPKs module that transduces dual stress signals, coupling with the SA pathway initiation to ultimately activate HTAS resistance against Pst in XY6.

Genome-wide identification of TGA transcription factors in wheat and the TaTGA13 negatively modulates stripe rust resistance.

Wheat stripe rust, caused by the biotrophic fungal pathogen Puccinia striiformis f. sp. tritici (Pst), is among the top crop diseases incurring huge economic losses worldwide. Identification of new stripe rust resistant sources that can be easily used in wheat cultivar development is essential for food security. PI 622129, an Iranian wheat landrace, exhibits high resistance to the predominant U.S. Pst races. A recombinant inbred line (RIL) population from the cross PI 622129 × Stardust was genotyped using SNPs generated by genotyping-by-sequencing. The RIL population was evaluated for responses to the Pst race PSTv-37 at the seedling stage in three environments, and quantitative trait loci (QTL) analysis revealed four QTL for stripe rust resistance on chromosome arms 2DS, 5BS, 2AL, and 7BL. Of these, QYr.stars-2DS and QYr.stars-5BS are major QTL explaining 21-38% and 11.6-27.2% of the total phenotypic variance, respectively, in three experiments. QYr.stars-2DS is a new stripe rust resistance locus that was identified in the interval of 2.58-5.54 Mb on chromosome arm 2DS based on the Chinese Spring IWGSC RefSeq v2.1 reference genome. Another QTL, QYr.stars-5BS, is close to Yr47 and was delimited to the interval 8.1 - 9.0 Mb in the reference genome. QYr.stars-2AL and QYr.stars-7BL were mapped to the terminal and QTL-rich regions on chromosome arms 2AL (750.8 - 752.5 Mb) and 7BL (718.1 - 721.2 Mb), respectively. KASP markers were developed to facilitate the rapid introgression of these QTL into locally adapted lines via marker-assisted selection.

Wheat stripe rust, caused by the fungus Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating diseases affecting wheat production globally. Its epidemic potential, capacity for rapid genetic evolution, and ability to cause significant yield losses make it a persistent threat to global food security. Traditional management approaches, primarily reliant on resistant cultivars and fungicide applications, have been challenged by the emergence of new virulent pathogen races and issues of fungicide resistance. In this context, there is an urgent need to develop and implement sustainable control strategies as part of integrated management systems for wheat stripe rust. Such approaches must balance efficacy, economic viability, environmental stewardship, and social acceptability. This paper provides an in-depth overview of sustainable control strategies within integrated management frameworks for wheat stripe rust, synthesizing recent advances in plant pathology, crop management, energy systems, sustainability science, and digital agriculture. By drawing on cross-disciplinary insights, especially from energy management, industrial process control, and sustainability integration in business and agricultural systems, this review elucidates how innovation in control strategies can address the multifaceted challenges posed by wheat stripe rust.

Wild grasses can serve as hosts for plant pathogens that attack small grain cereal crops, thereby perpetuating the disease cycle and potentially initiating epidemics. Foxtail barley (Hordeum jubatum) is a perennial grass species that is common across North America and can often be found growing near cultivated barley fields. Despite the close proximity of the two plant species in agroecosystems, few studies have been advanced to characterize the compatibility of H. jubatum to barley pathogens and its possible role in disease epidemiology. The objective of this study was to assess whether H. jubatum can act as a host to seven fungal pathogens causing diseases of barley. A collection of H. jubatum accessions (n = 100) from sites in Minnesota, Wisconsin, and North Dakota in the United States and Manitoba in Canada were inoculated at the seedling or adult plant stage in the greenhouse with isolates of Drechslera teres f. teres (causal pathogen of net form net blotch), Bipolaris sorokiniana (spot blotch), Puccinia graminis f. sp. tritici (stem rust), Blumeria graminis f. sp. hordei (powdery mildew), Puccinia striiformis f. sp. hordei (stripe rust), Puccinia hordei (leaf rust), and P. coronati-hordei (crown rust). None of the accessions showed any visual signs of infection when challenged with B. graminis f. sp. hordei and P. hordei. In contrast, 97 to 100% of evaluated accessions were infected by D. teres f. teres, B. sorokiniana, P. graminis f. sp. tritici, P. striiformis f. sp. hordei, and P. coronati-hordei. The relative degree of compatibility of H. jubatum to these latter five pathogens ranged from low (similar to resistant barley) to high (similar to susceptible barley). These results demonstrate that H. jubatum can be infected by isolates of important barley pathogens, but typically not with the same degree of compatibility as susceptible barleys. Nevertheless, when infected plants of H. jubatum are growing near barley fields, they could serve as reservoirs of inoculum to initiate some diseases.

IntroductionIn North India, Puccinia striiformis f. sp. triticii (Pst), the causal agent of stripe rust, poses a significant challenge to wheat productivity. The frequent emergence of new virulent Pst strains has rendered many resistance genes ineffective. Hence, continuous identification and deployment of novel resistance genes are crucial for maintaining durable resistance and ensuring sustainable wheat cultivation.Materials and MethodsA genome-wide association study (GWAS) was conducted on 652 elite, diverse wheat genotypes using 1,938 DArTseq SNP markers. Field evaluations were performed at the adult plant stage across four locations—Hisar, Karnal, Gurdaspur, and Khudwani—under natural disease conditions. Marker–trait associations were identified using General Linear Model (GLM), Mixed Linear Model (MLM), and FarmCPU approaches, considering loci with –log₁₀(p) ≥ 3 as significant.ResultsAnalysis revealed 27 genomic regions significantly associated with stripe rust resistance across environments. Among these, four loci were located on chromosomes 2B and 6B, and three on 6A. Several loci corresponded to resistance-related genes, including NBS-LRR, F-box, LRR, protein kinase, Ser/Thr_kinase, Znf_RING-CH, E3-ubiquitin ligase, and ABC transporter genes, suggesting their potential role in rust resistance mechanisms.DiscussionThe study identified novel genomic regions associated with Pst resistance, providing valuable resources for wheat improvement. The functional annotation of these loci highlights their involvement in plant defense pathways. Conversion of these loci into breeder-friendly molecular markers will facilitate marker-assisted selection (MAS) and accelerate the development of durable stripe rust-resistant wheat cultivars suited to North Indian agro-ecological conditions.

Plasticity in initial infection traits in response to high temperature for worldwide representative Puccinia striiformis isolates.

Wheat stripe rust (Puccinia striiformis f. sp. tritici, Pst) poses a catastrophic threat to global food security. While MADS-box transcription factors regulate development and abiotic stress, their roles in plant-pathogen immunity remain enigmatic. In this study, we identified TaMADS2, a Pst-induced MADS-box gene, as a positive regulator of wheat resistance. Functional analyses demonstrated that TaMADS2 overexpression significantly enhanced Pst resistance, whereas its knockdown rendered wheat more susceptible. Further investigation revealed that TaMADS2 interacts with trichome birefringence-like protein 21 (TaTBL21) to activate glycerol kinase-like (TaGKL) expression. Silencing TaGKL in wild-type or TaMADS2-overexpressing lines compromised resistance, with elevated Pst biomass. Notably, dual silencing of TaMADS2 and TaGKL further heightened susceptibility, confirming their synergistic defence role. Mechanistically, the TaMADS2-TaTBL21 complex promotes wheat resistance to stripe rust disease by upregulating TaGKL expression, leading to the accumulation of the key defence metabolites salicylic acid (SA) and glycerol-3-phosphate (G3P). Our study unveils a novel TaMADS2-TaTBL21-TaGKL module that potentiates wheat resistance against stripe rust, offering strategic targets for breeding resistant wheat.

Comparative defense profiling in wheat near-isogenic lines reveals mechanistic diversity among stripe rust resistance (Yr) genes conferring uniform infection type against Puccinia striiformis f. sp. tritici

TuNHL1, an NDR1/HIN1 like gene, is essential for YrU1-mediated stripe rust resistance and enhances powdery mildew resistance in plants.

Durum wheat (Triticum turgidum ssp. durum) suffers substantial yield losses from yellow rust (Puccinia striiformis) and leaf rust (Puccinia triticina). In this study, we employed genome‐wide association studies (GWAS) to identify loci associated with rust resistance and used genomic selection (GS) to evaluate the predictive accuracy of different statistical models and phenotyping metrics (AUDPC_GDD, Angle, GDD50, and maxVar) in a Canadian durum wheat panel. The panel was evaluated in Mexico for yellow rust across three seasons near Toluca, and for leaf rust over two seasons at El Batán. Our GWAS identified 36 significant marker‐trait associations (MTAs), including known loci (Yr30, Yr57, Yr82, YrU1, Lr16, Lr17, Lr18, and Lr65) and previously unreported regions. Yellow rust resistance was linked to loci on chromosomes 3A (602.7 Mbp) and 3B (243.4 Mbp), while leaf rust MTAs appeared on chromosomes 5A (552.8 Mbp) and 7A (570 Mbp). Candidate genes near novel MTAs encode defense‐related proteins such as serine/threonine kinases and NB‐ARC (nucleotide binding–Apaf‐1, R proteins, and CED‐4), F‐box, and RIN4 (RPM1‐interacting protein 4)‐domain proteins. Among four scoring metrics tested, AUDPC_GDD consistently outperformed others for yellow rust, whereas maxVar was most effective for leaf rust, reflecting differences in phenotypic distribution and trait variance. Bayesian GS models (BayesB) achieved the highest prediction accuracy, but including GWAS‐derived fixed effects did not improve predictions, likely due to complexities in modeling major‐effect loci. These results underscore the importance of rust‐specific phenotyping strategies and illustrate the difficulty of integrating GWAS into GS models to dissect complex resistance traits.

In the plant ecosystem, microbiomes are of great significance in sustaining plant health, participating in multiple physiological activities like nutrient metabolism, stress resistance, and hormone regulation. However, the invasion of pathogens like Puccinia striiformis can disrupt the balance of the plant microbiome, significantly affecting plant growth, development, and metabolism. This study delved into the responses of wheat microbial communities in different niches, namely the phyllosphere and rhizosphere, to P. striiformis infection. The structure of the phyllosphere fungal community was predominantly affected by the wheat variety. The α–diversity of phyllosphere fungi increased with the enhancement of wheat resistance. In the rhizosphere, although the inoculation did not cause a notable alteration to the overall architecture of the bacterial and fungal communities, remarkable variations were detected in the relative proportion of certain microbial taxa across various resistant wheat varieties. The co-occurrence network of the rhizosphere underwent significant structural and functional reorganization, and the network became substantially more complex after inoculation. The study also uncovered the interaction among the microbial communities in the phyllosphere and rhizosphere, with highly resistant varieties showing a stronger ability to coordinate this interaction to optimize microbial community functions and enhance disease resistance. This research deepens the understanding of the wheat—Puccinia striiformis—microbial community interaction system and paves the way for further research on wheat disease prevention and control strategies.

Transcriptional and post-translational regulation of wheat TaWRKY40 orchestrates ROS-mediated plant resistance against stripe rust.

Yellow rust, also known as stripe rust, is a significant disease that affects wheat in Iraq. The current study was conducted to study host-parasite interaction of some durum wheat cultivars with the new yellow rust (Puccinia striiformis f. sp. tritici) (Pst) races at adult plant stage in the field during the growing seasons, 2021 to 2023 under rain fed conditions in Sulaimani. Furthermore, Agricultural characteristics of the tested durum cultivar were also determined in the presence of the disease. The findings revealed that most durum wheat cultivars were moderately susceptible to susceptible to yellow rust disease under Sulaimani environmental conditions. The mean coefficient of yellow rust infection ranged from 1.73 in Ofanto to 23 in Cham-5. However, some cultivars, such as Cham-1, Fadda-98, and Ofanto, displayed moderate resistance response to the disease, while others, like Bhuth-5 and Acsad-65, showed moderate susceptibility. Yellow rust parameters (Diseases severity, infection type and coefficient of infection) were higher in 2023 season compared to 2022 in most of the tested cultivars. Additionally, the moderate resistant cultivar cv. Fadda-98 displayed distinct in some plant traits compared to other durum wheat cultivars, such as plant height (101.12cm), awn length (14.21cm), number of grains per spike (60.22), grain weight per spike (2.92g), biological yield (2292.4 g/m2), and grain yield (783.13). The study finding enhances wide cultivation of cv. Fadda-98 in the hot spot of yellow rust lands in Iraq.

This article examines the effect of yellow rust (Puccinia striiformis West.) and powdery mildew (Erysiphe graminis D.C.) on the protein content of winter wheat grain and the effectiveness of chemical agents for their prevention. The studies were conducted in the Kashkadarya region, and various fungicides were used in field experiments. As a result, it was found that the diseases significantly reduce the protein content of wheat grain, negatively affect the quality of the crop, and the use of chemicals limits the spread of diseases, helps to increase the protein content in grain and improve the quality of the crop. Some fungicides also showed high economic efficiency, ensuring the formation of high protein content in winter wheat.

Puccinia striiformis f. sp. tritici (Pst) and P. striiformis f. sp. hordei (Psh) cause stripe rust epidemics on wheat and barley, respectively. Demethylation inhibitor (DMI) fungicides have been used for decades in managing stripe rust in the United States, but the pathogen tolerance was not clear. To determine the dynamics of DMI fungicide targeting gene Cyp51 mutants, Pst isolates collected from 1968 to 2021 and Psh isolates from 1993 to 2021 were tested using a Kompetitive Allele Specific PCR (KASP) marker for the Y134F point mutation in the Cyp51 gene. The mutant allele was found in the Pst and Psh populations as early as in 1968 and 1993, respectively, and the mutant frequencies fluctuated from year to year. The KASP test of the Pst-infected leaf samples from fungicide-testing plots in 2024 revealed that the application of DMI fungicide Tilt increases the mutant frequency. The urediniospore germination tests with 22 selected isolates at different concentrations of Tilt showed that the mean EC50 value of the homozygous mutant isolates was 2.7 times higher than that of the wild type isolates, but those of the heterozygous and wild type isolates were not significantly different from each other. The results indicate that the KASP marker is useful in monitoring the DMI fungicide targeting gene mutants and DMI fungicides are likely less effective in controlling the homozygous mutant population than the wild type and heterozygous populations. The information is useful for managing stripe rust using diverse fungicides as well as growing resistant cultivars.

Puccinia striiformis f. sp. tritici, causing stripe rust, is one of the most prominent pathogens of wheat worldwide. The biotrophic and obligate fungus is capable of rapid developing new virulent races that can overcome race-specific resistance in host plants. The traditional virulence characterization of the pathogen requires strict conditions for testing isolates on wheat differentials with specific resistance genes, which is time consuming. Developing molecular markers for avirulence genes could provide an efficient method for monitoring virulence changes in the pathogen population. In this study, secreted protein (SP) gene-based single nucleotide polymorphism (SNP) markers previously identified to be associated with avirulence genes of the pathogen were converted to Kompetitive Allele Specific PCR (KASP) markers. The KASP markers were screened with a diverse panel of 192 isolates selected from various countries based on their virulent races and molecular genotypes. The markers significantly correlated to the avirulence/virulence phenotypic data of the 192 isolates were further validated with 845 isolates collected from the United States in 2019-2021. Based on the results of both the screening and validation data, 21 KASP markers significantly associated with different avirulence genes were developed. Seventeen of the 21 markers were significantly associated with two or more avirulence genes, and except AvrYr10, and the remaining 15 avirulence genes had two or more markers. Different combinations of up to three markers could be used for specific detection of 16 avirulence genes in monitoring the pathogen population.