scholarly journals Development of Race-Specific SCAR Markers for Detection of Chinese Races CYR32 and CYR33 of Puccinia striiformis f. sp. tritici

Plant Disease ◽  
2010 ◽  
Vol 94 (2) ◽  
pp. 221-228 ◽  
Author(s):  
Baotong Wang ◽  
Xiaoping Hu ◽  
Qiang Li ◽  
Baojun Hao ◽  
Bo Zhang ◽  
...  

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is a devastating disease in China. Races CYR32 and CYR33 have been predominant in the recent P. striiformis f. sp. tritici population. To develop molecular markers for these races, initially 86 isolates, most of which were collected in 2007 throughout China, were tested on the set of wheat genotypes for differentiating Chinese P. striiformis f. sp. tritici races, and their genomic DNA were amplified with 94 random amplified polymorphic DNA (RAPD) primers. Twelve isolates were identified as CYR33, 14 as CYR32, and 60 as 13 other races. A 320-bp band was identified to be associated with CYR32 with primer S1271 (5′-CTTCTCGGTC-3′), and a 550-bp band was identified to be specific to CYR33 with primer S1304 (5′-AGGAGCGACA-3′). The two bands were cloned and sequenced. Based on the sequences, sequence characterized amplified region (SCAR) markers CYR32sp1/sp2 and CYR33sp1/sp2 were developed to differentiate CYR32 and CYR33, respectively, from other races. The SCAR markers were validated with DNA samples from wheat leaves inoculated with selected isolates from the 86 isolates and urediniospore DNA samples from an additional 63 isolates collected from 2006 to 2009. The detection of CYR32 and CYR33 with the SCAR markers was completely consistent with the results of the race identification with the set of differential wheat genotypes. Thus, the markers are highly reliable for identification of the two races.

Plant Disease ◽  
2021 ◽  
Author(s):  
Mercy Wamalwa ◽  
Ruth Wanyera ◽  
Julian Rodriguez-Algaba ◽  
Lesley Boyd ◽  
James Owuoche ◽  
...  

Stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici (Pst), is a major threat to wheat (Triticum spp.) production worldwide. The objective of this study was to determine the virulence of Pst races prevalent in the main wheat growing regions of Kenya, which includes Mt. Kenya, Eastern Kenya, and the Rift Valley (Central, Southern, and Northern Rift). Fifty Pst isolates collected from 1970 to 1992 and from 2009 to 2014 were virulence phenotyped using stripe rust differential sets, and 45 isolates were genotyped with sequence characterized amplified region (SCAR) markers to differentiate among the isolates and identify aggressive strains PstS1 and PstS2. Virulence corresponding to stripe rust resistance genes Yr1, Yr2, Yr3, Yr6, Yr7, Yr8, Yr9, Yr17, Yr25, Yr27 and the seedling resistance in genotype Avocet S were detected. Ten races were detected in the Pst samples obtained from 1970 to 1992, and three additional races were detected from 2009 to 2014, with a single race being detected in both periods. The SCAR markers detected both Pst1 and Pst2 strains in the collection. Increasing Pst virulence was found in the Kenyan Pst population, and that diverse Pst race groups dominated different wheat growing regions. Moreover, recent Pst races in east Africa indicated possible migration of some race groups into Kenya from other regions. This study is important in understanding Pst evolution and virulence diversity and useful in breeding wheat cultivars with effective resistance to stripe rust. Keywords: pathogenicity, Puccinia f. sp. tritici stripe (yellow) rust, Triticum aestivum


Plant Disease ◽  
2016 ◽  
Vol 100 (9) ◽  
pp. 1840-1847 ◽  
Author(s):  
L. Gao ◽  
H. X. Yu ◽  
X. H. Kang ◽  
H. M. Shen ◽  
C. Li ◽  
...  

Stripe rust, caused by the pathogenic fungus Puccinia striiformis f. sp. tritici, is an important disease of wheat worldwide. A rapid and reliable detection of the pathogen in latent infected wheat leaves is useful for accurate and early forecast of outbreaks and timely application of fungicides for managing the disease. Using the previously reported primer pair Bt2a/Bt2b, a 362-bp amplicon was obtained from P. striiformis f. sp. tritici and a 486-bp amplicon was obtained from both P. triticina (the leaf rust pathogen) and P. graminis f. sp. tritici (the stem rust pathogen). Based on the sequence of the 362-bp fragment, two pairs of sequence characterized amplified region (SCAR) primers were designed. PSTF117/PSTR363 produced a 274-bp amplicon and TF114/TR323 produced a 180-bp amplicon from P. striiformis f. sp. tritici, whereas they did not produce any amplicon from P. triticina, P. graminis f. sp. tritici, or any other wheat-infecting fungi. The detection limit of PSTF117/PSTR363 was 1 pg/µl and TF114/TR323 was 100 fg/µl. Both SCAR markers could be detected in wheat leaves 9 h post inoculation. An SYBR Green RT-PCR method was also developed to detect P. striiformis f. sp. tritici in infected leaves with the detection limit of 1.0 fg DNA from asymptomatic leaf samples of 6 h after inoculation. These methods should be useful for rapid diagnosis and accurate detection of P. striiformis f. sp. tritici in infected wheat leaves for timely control of the disease.


Plant Disease ◽  
2021 ◽  
Author(s):  
Mehmet Tekin ◽  
Ahmet Cat ◽  
Kadir Akan ◽  
Mursel Catal ◽  
Taner Akar

The gene Yr5 in wheat has generally been known to confer resistance to Puccinia striiformis f. sp. tritici races worldwide. However, a few reports indicated that some isolates of the stripe rust pathogen were virulent on the wheat genotypes with Yr5 in India, Australia, and China (Nagarajan 1986; Wellings and McIntosh 1990; Zhang et al. 2020). In April 2020, a stripe rust infection was observed on Triticum spelta ‘Album’ (TSA), the Yr5 donor, provided by Turkey Seed Gene Bank in a wheat breeding field at the experimental station of Akdeniz University in the Antalya province of Turkey. The sample was tested on the seedlings of the Yr single-gene lines in the Avocet S (AvS) background including Yr5 near-isogenic line (AvSYr5NIL), TSA, and susceptible bread wheat variety ‘Morocco’ according to the procedure reported by Wan et al. (2014), and found to be highly virulent on Morocco with infection type (IT) 9 and virulent on AvSYr5NIL and TSA with IT 7. To confirm this novel finding, single-pustule isolates derived from this sample were obtained from TSA and re-tested on the differentials and TSA. The Yr5-virulent isolate yielded similar infection types on these plants further verifying previous results. The single-pustule isolates were determined to be avirulent (Avr) (IT 0 to 6) on AvSYr1NIL, AvSYr8NIL, AvSYr9NIL, AvSYr10NIL, AvSYr32NIL, and AvSYr43NIL and virulent (Vr) (IT 7 to 9) on AvSYr5NIL, AvSYr6NIL, AvSYr7NIL, AvSYr17NIL, AvSYr24NIL, AvSYr27NIL, AvSYr44NIL, AvSYrSpNIL, and TSA. The isolates were identified as a new race and temporarily named TRVR20-5 based on its Avr/Vr pattern. Furthermore, to confirm the presence of Yr5, the genomic DNA of fresh leaves of AvSYr5NIL and TSA used in the virulence testing were isolated using NucleoSpin Plant II (Macherey-Nagel, Germany) according to the manufacturer’s procedure. The genomic DNA samples were amplified with the primers STS-7 (5′-GTACAATTCACCTAGAGT-3′) and STS-8 (5′-GCAAGTTTTCTCCCTATT-3′) (Chen et al. 2003) using a thermal cycler (T-100, BioRad, USA), and the resulting PCR products were digested with DpnII and visualized on an agarose gel. AvSYr5NIL and TSA had the fragment linked to the resistance allele (308 bp) whereas AvS and Morocco had the fragment linked to the susceptible allele (181 bp). Thus, both wheat genotypes were confirmed to carry Yr5, and the new Pst race virulent to Yr5 was confirmed. To the best of our knowledge, this is the first report of a Pst race virulent to Yr5 in Turkey, where stripe rust epidemics have occured in 2 out of every 5 years with 1-5% crop losses in over 25% of the wheat growing areas (Chen 2020). In a nutshell, monitoring the Pst races virulent to Yr5 with a potential to cause devastating epidemics worldwide is crucial due to the fact that international wheat breeding programs have been using Yr5 to develop wheat cultivars with resistance to stripe rust.


Agronomy ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 770 ◽  
Author(s):  
Mercy N. Wamalwa ◽  
James Owuoche ◽  
Joshua Ogendo ◽  
Ruth Wanyera

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the key diseases of economic importance in wheat worldwide. Host resistance, which follows the gene-for-gene hypothesis between the host and pathogen, has been used in wheat lines to resolve resistance specificities and postulate resistant genes. The objective of this study was to elucidate stripe rust resistance in a collection of Kenyan wheat lines and Watkin landraces to identify new sources of stripe rust (Yr) resistance. In this study, the resistance in twenty wheat lines was determined by comparing their infection type with those of twenty differential lines using isolates representing twelve Puccinia striiformis races from Kenya, Denmark, U.K., Sweden, and Eritrea at the seedling stage. Among the twenty wheat lines, none was resistant to all the twelve Pst races and isolate DK02d/12 (“Kranich” race) was virulent on all the genotypes except wheat genotype “Kenya Tai.” This genotype (“Kenya Tai”) had the highest resistance as it was resistant to all the twelve stripe rust races used in this study. From this study, the introduction and utilization of wheat genotypes with adult plant resistant (APR) stripe rust genes, such as Yr15, are important in breeding wheat genotypes with effective resistance to wheat stripe rust in Kenya and worldwide.


Plant Disease ◽  
2020 ◽  
Vol 104 (9) ◽  
pp. 2434-2439 ◽  
Author(s):  
Furong Peng ◽  
Miu Si ◽  
Yang Zizhu ◽  
Yuhang Fu ◽  
Yuheng Yang ◽  
...  

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important and devastating diseases of wheat; therefore, it is necessary to rapidly and accurately quantify fungicide effectiveness to monitor Pst sensitivity and manage the disease. In this study, a rapid method of quantifying the fungicide effectiveness with detached leaves was developed. The results showed that 0.5% water agar containing 75 μg/ml of 6-benzylaminopurine and filter paper worked the best for maintaining wheat leaves. The disease incidences of different concentrations of spore suspension were compared. When the spore concentrations were 5 and 10 mg/ml, the disease incidences had no significant differences at 12 and 15 days after inoculation (P < 0.05). Fungicide treatment tests revealed that there were no significant differences in the efficacies of triadimefon on rust suppression between detached leaves in the culture dishes and direct spray on seedlings. We also developed a Photoshop software method that can replace the current classification method and accurately measure the proportion of sporulation area on infected leaves. The sensitivity baseline of Pst to triadimefon was estimated as 0.1453 ± 0.0081 μg/ml, and all the values of EC50 were tested for normal distribution using the Shapiro–Wilk test (W = 0.204). The baseline can be used to test the sensitivity of different Pst isolates to triadimefon.


2014 ◽  
Vol 62 (4) ◽  
pp. 1649 ◽  
Author(s):  
Luquan Yang ◽  
Md. Asaduzzaman Khan ◽  
Zhiqiang Mei ◽  
Manman Yang ◽  
Tiandan Zhang ◽  
...  

<p>Genetic diversity within a species is a common feature, which plays a vital role in its survival and adaptability, and is important for the identification and authentication of a species. <em>Lonicera japonica</em> is a traditionally used medicinal plant, which have been recently genetically characterized by an improved random amplified polymorphic DNA (RAPD) analysis. In this study, the molecular markers on the basis of these RAPD fragments have been developed to identify specific <em>L. japonica</em> variety. The DNAs were extracted from fresh young leaves of different samples of <em>L. japonica</em> collected from Shenzhen, Yichang, Leshan, Emei and Loudi, China. The DNA materials were amplified using improved RAPD PCR. Different RAPD bands were excised, cloned and developed for stable sequence-characterized amplified region (SCAR) markers with different species. Two SCAR markers, JYH3-3 and JYH4-3, have been successfully cloned from improved RAPD fragments. The SCAR marker JYH3-3 was found specific for all of the <em>L. japonica</em> samples collected from the different regions, and another marker JYH 4-3 was strictly specific to the Shenzhen sample from Guangdong province, which is geographically distant from Hubei, Sichuan and Hunan Provinces (source of other <em>L. japonica</em> samples). The marker JYH3-3 was found as specific molecular marker for the identification of <em>L. japonica</em>, while JYH4-3 was found as molecular marker strictly specific for the Shenzhen sample. The developed SCAR markers might serve as more specific molecular markers for <em>L. japonica</em> variety authentication. The combination of improved RAPD analysis and SCAR marker development have resulted useful tools to study the genetic variety of any organism, which we have successfully applied here in <em>L. japonica</em>.</p><p>de cualquier organismo, que hemos aplicado con éxito en <em>L. japonica</em>.<strong></strong></p>


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jan Bettgenhaeuser ◽  
Inmaculada Hernández-Pinzón ◽  
Andrew M. Dawson ◽  
Matthew Gardiner ◽  
Phon Green ◽  
...  

AbstractCrop losses caused by plant pathogens are a primary threat to stable food production. Stripe rust (Puccinia striiformis) is a fungal pathogen of cereal crops that causes significant, persistent yield loss. Stripe rust exhibits host species specificity, with lineages that have adapted to infect wheat and barley. While wheat stripe rust and barley stripe rust are commonly restricted to their corresponding hosts, the genes underlying this host specificity remain unknown. Here, we show that three resistance genes, Rps6, Rps7, and Rps8, contribute to immunity in barley to wheat stripe rust. Rps7 cosegregates with barley powdery mildew resistance at the Mla locus. Using transgenic complementation of different Mla alleles, we confirm allele-specific recognition of wheat stripe rust by Mla. Our results show that major resistance genes contribute to the host species specificity of wheat stripe rust on barley and that a shared genetic architecture underlies resistance to the adapted pathogen barley powdery mildew and non-adapted pathogen wheat stripe rust.


2005 ◽  
Vol 95 (8) ◽  
pp. 884-889 ◽  
Author(s):  
Vihanga Pahalawatta ◽  
Xianming Chen

Most barley cultivars are resistant to stripe rust of wheat that is caused by Puccinia striiformis f. sp. tritici. The barley cv. Steptoe is susceptible to all identified races of P. striiformis f. sp. hordei (PSH), the barley stripe rust pathogen, but is resistant to most P. striiformis f. sp. tritici races. To determine inheritance of the Steptoe resistance to P. striiformis f. sp. tritici, a cross was made between Steptoe and Russell, a barley cultivar susceptible to some P. striiformis f. sp. tritici races and all tested P. striiformis f. sp. hordei races. Seedlings of parents and F1, BC1, F2, and F3 progeny from the barley cross were tested with P. striiformis f. sp. tritici races PST-41 and PST-45 under controlled greenhouse conditions. Genetic analyses of infection type data showed that Steptoe had one dominant gene and one recessive gene (provisionally designated as RpstS1 and rpstS2, respectively) for resistance to races PST-41 and PST-45. Genomic DNA was extracted from the parents and 150 F2 plants that were tested for rust reaction and grown for seed of F3 lines. The infection type data and polymorphic markers identified using the resistance gene analog polymorphism (RGAP) technique were analyzed with the Mapmaker computer program to map the resistance genes. The dominant resistance gene in Steptoe for resistance to P. striiformis f. sp. tritici races was mapped on barley chromosome 4H using a linked microsatellite marker, HVM68. A linkage group for the dominant gene was constructed with 12 RGAP markers and the microsatellite marker. The results show that resistance in barley to the wheat stripe rust pathogen is qualitatively inherited. These genes might provide useful resistance against wheat stripe rust when introgressed into wheat from barley.


Sign in / Sign up

Export Citation Format

Share Document