Identification of Stripe Rust Resistance in Ethiopian Durum Wheat by Phenotypic Screening and Kompetitive Allele Specific PCR (KASP) SNP Markers

Abstract Background Maize is one of the most important field crops in the world. Most of the key agronomic traits, including yield traits and plant architecture traits, are quantitative. Fine mapping of genes/ quantitative trait loci (QTL) influencing a key trait is essential for marker-assisted selection (MAS) in maize breeding. However, the SNP markers with high density and high polymorphism are lacking, especially kompetitive allele specific PCR (KASP) SNP markers that can be used for automatic genotyping. To date, a large volume of sequencing data has been produced by the next generation sequencing technology, which provides a good pool of SNP loci for development of SNP markers. In this study, we carried out a multi-step screening method to identify kompetitive allele specific PCR (KASP) SNP markers based on the RNA-Seq data sets of 368 maize inbred lines. Results A total of 2,948,985 SNPs were identified in the high-throughput RNA-Seq data sets with the average density of 1.4 SNP/kb. Of these, 71,311 KASP SNP markers (the average density of 34 KASP SNP/Mb) were developed based on the strict criteria: unique genomic region, bi-allelic, polymorphism information content (PIC) value ≥0.4, and conserved primer sequences, and were mapped on 16,161 genes. These 16,161 genes were annotated to 52 gene ontology (GO) terms, including most of primary and secondary metabolic pathways. Subsequently, the 50 KASP SNP markers with the PIC values ranging from 0.14 to 0.5 in 368 RNA-Seq data sets and with polymorphism between the maize inbred lines 1212 and B73 in in silico analysis were selected to experimentally validate the accuracy and polymorphism of SNPs, resulted in 46 SNPs (92.00%) showed polymorphism between the maize inbred lines 1212 and B73. Moreover, these 46 polymorphic SNPs were utilized to genotype the other 20 maize inbred lines, with all 46 SNPs showing polymorphism in the 20 maize inbred lines, and the PIC value of each SNP was 0.11 to 0.50 with an average of 0.35. The results suggested that the KASP SNP markers developed in this study were accurate and polymorphic. Conclusions These high-density polymorphic KASP SNP markers will be a valuable resource for map-based cloning of QTL/genes and marker-assisted selection in maize. Furthermore, the method used to develop SNP markers in maize can also be applied in other species.

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Molecular Mapping of a Novel QTL Conferring Adult Plant Resistance to Stripe Rust in Chinese Wheat Landrace ‘Guangtoumai’

Plant Disease ◽

10.1094/pdis-07-20-1544-re ◽

2020 ◽

Author(s):

Yu Wu ◽

Yuqi Wang ◽

Fangjie Yao ◽

Li Long ◽

Jing Li ◽

...

Keyword(s):

Stripe Rust ◽

Plant Resistance ◽

Rust Resistance ◽

Adult Plant Resistance ◽

Snp Markers ◽

Stripe Rust Resistance ◽

Adult Plant ◽

Major Locus ◽

Dcaps Marker ◽

Chinese Wheat

Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat in the world. Chinese wheat landrace ‘Guangtoumai’ (GTM) exhibited a high-level resistance against predominant Pst races in China at the adult-plant stage. The objective of this research was to identify and map the major locus/loci for stripe rust resistance in GTM. A set of 212 recombinant inbred lines (RILs) was developed from a cross between GTM and Avocet S (AvS). The parents and RILs were evaluated in three field tests (2018, 2019, and 2020 at Chongzhou, Sichuan) with the currently predominant Pst races for final disease severity (FDS) and genotyped with the Wheat 55K SNP array to construct a genetic map with 1,031 SNP markers. A major locus, named QYr.GTM-5DL, was detected on chromosome 5DL in GTM. The locus was mapped in a 2.75 cM interval flanked by SNP markers AX-109855976 and AX-109453419, explaining up to 44.4% of the total phenotypic variation. Since no known Yr genes have been reported on chromosome 5DL, QYr.GTM-5DL is very likely a novel adult plant resistance (APR) locus. Haplotype analysis revealed that the resistance allele displayed enhanced levels of stripe rust resistance and is likely present in 5.3% of the 247 surveyed Chinese wheat landraces. The derived cleaved amplified polymorphic sequence (dCAPS) marker dCAPS-5722, converted from a SNP marker tightly linked to QYr.GTM-5DL with 0.3 cM, was validated on a subset of RILs and 48 commercial wheat cultivars developed in Sichuan. The results indicated that QYr.GTM-5DL with its linked dCAPS marker could be used in marker-assisted selection to improve stripe rust resistance in breeding programs, and this QTL will provide new and possibly durable resistance to stripe rust.

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Genome-wide Mapping for Stripe Rust Resistance Loci in Common Wheat Cultivar Qinnong 142

Plant Disease ◽

10.1094/pdis-05-18-0846-re ◽

2019 ◽

Vol 103 (3) ◽

pp. 439-447 ◽

Cited By ~ 4

Author(s):

Qingdong Zeng ◽

Jianhui Wu ◽

Shengjie Liu ◽

Xianming Chen ◽

Fengping Yuan ◽

...

Keyword(s):

Resistance Gene ◽

Stripe Rust ◽

Rust Resistance ◽

Puccinia Striiformis ◽

Wheat Cultivar ◽

Infection Type ◽

Snp Markers ◽

Stripe Rust Resistance ◽

Adult Plant ◽

Wheat Cultivars

Stripe rust caused by Puccinia striiformis f. sp. tritici threatens worldwide wheat production. Growing resistant cultivars is the best way to control this disease. Chinese wheat cultivar Qinnong 142 (QN142) has a high level of adult-plant resistance to stripe rust. To identify quantitative trait loci (QTLs) related to stripe rust resistance, we developed a recombinant inbred line (RIL) population from a cross between QN142 and susceptible cultivar Avocet S. The parents and 165 F6 RILs were evaluated in terms of their stripe rust infection type and disease severity in replicated field tests with six site-year environments. The parents and RILs were genotyped with single-nucleotide polymorphism (SNP) markers. Four stable QTLs were identified in QN142 and mapped to chromosome arms 1BL, 2AL, 2BL, and 6BS. The 1BL QTL was probably the known resistance gene Yr29, the 2BL QTL was in a resistance gene-rich region, and the 2AL and 6BS QTLs might be new. Kompetitive allele specific polymerase chain reaction markers developed from the SNP markers flanking these QTLs were highly polymorphic in a panel of 150 wheat cultivars and breeding lines. These markers could be used in marker-assisted selection for incorporating the stripe rust resistance QTL into new wheat cultivars.

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Validation of SNP markers associated with ascochyta blight resistance in pea

Canadian Journal of Plant Science ◽

10.1139/cjps-2018-0211 ◽

2019 ◽

Vol 99 (2) ◽

pp. 243-249

Author(s):

Ambuj B. Jha ◽

Krishna K. Gali ◽

Sabine Banniza ◽

Thomas D. Warkentin

Keyword(s):

Association Studies ◽

Ascochyta Blight ◽

Snp Markers ◽

Blight Resistance ◽

Maturity Stage ◽

Single Nucleotide ◽

Specific Pcr ◽

Allele Specific ◽

Allele Specific Pcr ◽

Important Disease

Ascochyta blight of pea is an important disease that can cause severe yield loss. Our previous studies identified several closely linked single nucleotide polymorphism (SNP) markers associated with ascochyta blight resistance. The objective of this study was to validate SNP markers in 36 cultivars from the Saskatchewan pea regional variety trial. Ascochyta blight scores ranged from 1.0 to 9.0 at the physiological maturity stage under field conditions across the 25 site–years in Saskatchewan from 2013 to 2017. Based on Kompetitive Allele-Specific PCR assays, six SNP markers were used for an association study. SNP markers RGA-G3Ap103, PsC8780p118, and PsC22609p103 were significantly (P < 0.05) associated with ascochyta blight scores in 2013 and 2016 at Saskatoon. PsC8780p118 was significantly associated with ascochyta blight scores at Milden in 2014 and Rosthern in 2017. Furthermore, RGA-G3Ap103 showed significant association at Milden in 2014. Based on association studies, RGA-G3Ap103 and PsC8780p118 may have some potential as markers for pea breeding.

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Barley Stripe Rust Resistance QTL: Development and Validation of SNP Markers for Resistance to Puccinia striiformis f. sp. hordei

Phytopathology ◽

10.1094/phyto-09-15-0225-r ◽

2016 ◽

Vol 106 (11) ◽

pp. 1344-1351 ◽

Cited By ~ 14

Author(s):

K. Esvelt Klos ◽

T. Gordon ◽

P. Bregitzer ◽

P. Hayes ◽

X. M. Chen ◽

...

Keyword(s):

Stripe Rust ◽

Rust Resistance ◽

Puccinia Striiformis ◽

Recombinant Inbred Lines ◽

Snp Markers ◽

Stripe Rust Resistance ◽

Adult Plant ◽

Seedling Resistance ◽

Resistance Qtl ◽

Barley Stripe Rust

Quantitative trait loci (QTL) for barley stripe rust resistance were mapped in recombinant inbred lines (RIL) from a ‘Lenetah’ × ‘Grannelose Zweizeilige’ (GZ) cross. GZ is known for a major seedling resistance QTL on chromosome 4H but linked markers suitable for marker-assisted selection have not been developed. This study identified the 4H QTL (log of the likelihood [LOD] = 15.94 at 97.19 centimorgans [cM]), and additional QTL on chromosomes 4H and 6H (LOD = 5.39 at 72.7 cM and 4.24 at 34.46 cM, respectively). A QTL on chromosome 7H (LOD = 2.04 at 81.07 cM) was suggested. All resistance alleles were derived from GZ. Evaluations of adult plant response in Corvallis, OR in 2013 and 2015 provided evidence of QTL at the same positions. However, the minor QTL on 4H was not statistically significant in either location/year, while the 7H QTL was significant in both. The single-nucleotide polymorphism markers flanking the resistance QTL were validated in RIL from a ‘95SR316A’ × GZ cross for their ability to predict seedling resistance. In 95SR316A × GZ, 91 to 92% of RIL with GZ alleles at the major 4H QTL and at least one other were resistant to moderate in reaction. In these populations, at least two QTL were required to transfer the barley stripe rust resistance from GZ.

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Genomic Regions Associated With Stripe Rust Resistance Against the Egyptian Race Revealed by Genome-Wide Association Study

10.21203/rs.3.rs-57243/v1 ◽

2020 ◽

Author(s):

Abou-Zeid A. Mohamed ◽

Amira M. I. Mourad

Keyword(s):

Stripe Rust ◽

Spring Wheat ◽

Rust Resistance ◽

Genome Wide Association Study ◽

Snp Markers ◽

Genome Wide Association ◽

Stripe Rust Resistance ◽

Wheat Genotypes ◽

Genome Wide ◽

Resistant Genotypes

Abstract Background: Wheat stripe rust (caused by Puccinia striiformis f. sp. Tritici), is a major disease that causes huge yield damage. New pathogen races appeared in the last few years and caused a broke down in the resistant genotypes. In Egypt, some of the resistant genotypes began to be susceptible to stripe rust in recent years. This situation increases the need to produce new genotypes with durable resistance. Besides, looking for a new resistant source from the available wheat genotypes all over the world help in enhancing the breeding programs. Results: In the recent study, a set of 103-spring wheat genotypes from different fourteen countries were evaluated to their field resistant to stripe rust for two years. These genotypes included 17 Egyptian genotypes from the old and new cultivars. The 103-spring wheat genotypes were reported to be well adapted to the Egyptian environmental conditions. Out of the tested genotypes, eight genotypes from four different countries were found to be resistant in both years. Genotyping was carried out using genotyping-by-sequencing and a set of 26,703 SNPs were used in the genome-wide association study. Five SNP markers, located on chromosomes 2A and 4A, were found to be significantly associated with the resistance in both years. Three gene models associated with disease resistance and underlying these significant SNPs were identified. One immune Iranian genotype, with the highest number of different alleles from the most resistant Egyptian genotypes, was detected. Conclusion: the high variation among the tested genotypes in their resistance to the Egyptian stripe rust race confirming the possible improvement of stripe rust resistance in the Egyptian wheat genotypes. The identified five SNP markers are stable and could be used in marker-assisted selection after validation in different genetic backgrounds. Crossing between the immune Iranian genotype and the Egyptian genotypes will improve stripe rust resistance in Egypt.

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Molecular Fingerprinting and Hybridity Authentication in Cowpea Using Single Nucleotide Polymorphism Based Kompetitive Allele-Specific PCR Assay

Frontiers in Plant Science ◽

10.3389/fpls.2021.734117 ◽

2021 ◽

Vol 12 ◽

Author(s):

Patrick Obia Ongom ◽

Christian Fatokun ◽

Abou Togola ◽

Stella Salvo ◽

Oluwaseye Gideon Oyebode ◽

...

Keyword(s):

Single Nucleotide Polymorphism ◽

Principal Component ◽

Snp Markers ◽

Breeding Program ◽

Molecular Fingerprinting ◽

Nucleotide Polymorphism ◽

Single Nucleotide ◽

Specific Pcr ◽

Allele Specific ◽

Allele Specific Pcr

Optimization of a breeding program for increased genetic gain requires quality assurance (QA) and quality control (QC) at key phases of the breeding process. One vital phase in a breeding program that requires QC and QA is the choice of parents and successful hybridizations to combine parental attributes and create variations. The objective of this study was to determine parental diversity and confirm hybridity of cowpea F1 progenies using KASP (Kompetitive Allele-Specific PCR)-based single nucleotide polymorphism (SNP) markers. A total of 1,436 F1 plants were derived from crossing 220 cowpea breeding lines and landraces to 2 elite sister lines IT99K-573-1-1 and IT99K-573-2-1 as male parents, constituting 225 cross combinations. The progenies and the parents were genotyped with 17 QC SNP markers via high-throughput KASP genotyping assay. The QC markers differentiated the parents with mean efficiency of 37.90% and a range of 3.4–82.8%, revealing unique fingerprints of the parents. Neighbor-Joining cladogram divided the 222 parents into 3 clusters. Genetic distances between parents ranged from 0 to 3.74 with a mean of 2.41. Principal component analysis (PCA) depicted a considerable overlap between parents and F1 progenies with more scatters among parents than the F1s. The differentiation among parents and F1s was best contributed to by 82% of the markers. As expected, parents and F1s showed a significant contrast in proportion of heterozygous individuals, with mean values of 0.02 and 0.32, respectively. KASP markers detected true hybridity with 100% success rate in 72% of the populations. Overall, 79% of the putative F1 plants were true hybrids, 14% were selfed plants, and 7% were undetermined due to missing data and lack of marker polymorphism between parents. The study demonstrated an effective application of KASP-based SNP assay in fingerprinting, confirmation of hybridity, and early detection of false F1 plants. The results further uncovered the need to deploy markers as a QC step in a breeding program.

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