Molecular Cytogenetics and SLAF-seq-based Specific Molecular Markers for a Wheat–Aegilops geniculata 3M g Alien Addition Line with Resistance to Stripe Rust and Powdery Mildew

Abstract Background: Aegilops geniculata Roth is closely related to common wheat (Triticum aestivum L.) and is a valuable genetic resource for improvement of wheat. Results: In this study, the W19513 line was derived from the BC1F10 progeny of a cross between wheat ‘Chinese Spring’ and Ae. geniculata SY159. Cytological examination showed that W19513 contained 44 chromosomes. Twenty-two bivalents were formed at the first meiotic metaphase in the pollen mother cells, and the chromosomes were evenly distributed to opposite poles at meiotic anaphase. Genomic in situ hybridization demonstrated that W19513 carried a pair of alien chromosomes from the M genome. Fluorescence in situ hybridization confirmed detection of variation in chromosomes 4A and 6B. Functional molecular marker analysis using expressed sequence tag–sequence-tagged site and PCR-based landmark unique gene primers revealed that the alien gene belonged to the third homologous group. The marker analysis confirmed that the alien chromosome pair was 3Mg. In addition, to further explore the molecular marker specificity of chromosome 3Mg, based on the specific locus amplified fragment sequencing technique, molecular markers specific for W19513 were developed with efficiencies of up to 47.66%. The W19513 line was inoculated with the physiological race E09 of powdery mildew (Blumeria graminis f. sp. tritici) at the seedling stage and showed moderate resistance. Field inoculation with a mixture of the races CYR31, CYR32, CYR33, and CYR34 of the stripe rust fungus (Puccinia striiformis f. sp. triticii) revealed that the line W19513 showed strong resistance.Conclusions: This study provides a foundation for use of the line W19513 in future genetic research and wheat improvement.

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Molecular cytogenetics for a wheat–Aegilops geniculata 3Mg alien addition line with resistance to stripe rust and powdery mildew

BMC Plant Biology ◽

10.1186/s12870-021-03360-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yongfu Wang ◽

Xiaofang Cheng ◽

Xiaoying Yang ◽

Changyou Wang ◽

Hong Zhang ◽

...

Keyword(s):

In Situ Hybridization ◽

Powdery Mildew ◽

Molecular Marker ◽

Stripe Rust ◽

Puccinia Striiformis ◽

Addition Line ◽

Field Inoculation ◽

Aegilops Geniculata ◽

Marker Analysis

Abstract Background Aegilops geniculata Roth is closely related to common wheat (Triticum aestivum L.) and is a valuable genetic resource for improvement of wheat. Results In this study, the W19513 line was derived from the BC1F10 progeny of a cross between wheat ‘Chinese Spring’ and Ae. geniculata SY159. Cytological examination showed that W19513 contained 44 chromosomes. Twenty-two bivalents were formed at the first meiotic metaphase I in the pollen mother cellsand the chromosomes were evenly distributed to opposite poles at meiotic anaphase I. Genomic in situ hybridization demonstrated that W19513 carried a pair of alien chromosomes from the M genome. Fluorescence in situ hybridization confirmed detection of variation in chromosomes 4A and 6B. Functional molecular marker analysis using expressed sequence tag–sequence-tagged site and PCR-based landmark unique gene primers revealed that the alien gene belonged to the third homologous group. The marker analysis confirmed that the alien chromosome pair was 3Mg. In addition, to further explore the molecular marker specificity of chromosome 3Mg, based on the specific locus amplified fragment sequencing technique, molecular markers specific for W19513 were developed with efficiencies of up to 47.66%. The W19513 line was inoculated with the physiological race E09 of powdery mildew (Blumeria graminis f. sp. tritici) at the seedling stage and showed moderate resistance. Field inoculation with a mixture of the races CYR31, CYR32, CYR33, and CYR34 of the stripe rust fungus (Puccinia striiformis f. sp. triticii) revealed that the line W19513 showed strong resistance. Conclusions This study provides a foundation for use of the line W19513 in future genetic research and wheat improvement.

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Molecular Cytogenetic Characterization of a New T2BL·1RS Wheat-Rye Chromosome Translocation Line Resistant to Stripe Rust and Powdery Mildew

Plant Disease ◽

10.1094/pdis-93-2-0124 ◽

2009 ◽

Vol 93 (2) ◽

pp. 124-129 ◽

Cited By ~ 20

Author(s):

Chunmei Wang ◽

Qi Zheng ◽

Lihui Li ◽

Yongchun Niu ◽

Haibo Wang ◽

...

Keyword(s):

In Situ Hybridization ◽

Powdery Mildew ◽

Stripe Rust ◽

Expressed Sequence Tag ◽

Puccinia Striiformis ◽

Wheat Breeding ◽

Translocation Line ◽

Winter Rye ◽

New Genotype

Wheat (Triticum aestivum) genotypes with rye (Secale cereale) 1RS chromosomal translocations are widely used in wheat breeding programs because 1RS carries genes for resistance to several diseases. However, some of the pathogens have evolved into new races that overcome the resistance due to extensive use of cultivars with the resistance genes from rye. Therefore, identification and deployment of new resistance sources with desirable agronomic characteristics are important and urgent. We have used winter rye cultivar German White as a source of genes for desirable traits in wheat improvement. A new genotype named WR04-32 was produced through hybridization and chromosome manipulation between common winter wheat cultivar Xiaoyan 6 and German White. This genotype was highly resistant to a wide spectrum of the wheat stripe rust (Puccinia striiformis f. sp. tritici) and powdery mildew (Blumeria graminis f. sp. tritici) pathotypes prevalent in China. The polymerase chain reaction (PCR) result using EST-STS (expressed sequence tag-site tagged sequence) marker STSWE126 specific to 1RS confirmed 1RS in WR04-32, and it was further proved to be a wheat-rye T2BL·1RS translocation line using sequential genomic in situ hybridization (GISH) and multicolor fluorescence in situ hybridization (FISH) with probes pAs1 and pSc119.2 (or pHvG38). In addition to its resistance to stripe rust and powdery mildew, WR04-32 was genetically stable and had desirable agronomic traits, making it a desirable germplasm for wheat breeding.

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Assessment of resistance to cereal cyst nematode, stripe rust and powdery mildew in the wheat-Thinopyrum intermedium derivatives and their chromosome composition

Plant Disease ◽

10.1094/pdis-10-20-2141-re ◽

2021 ◽

Author(s):

Lei Cui ◽

Yongkang Ren ◽

Yinguang Bao ◽

Hai Nan ◽

Zhaohui Tang ◽

...

Keyword(s):

In Situ Hybridization ◽

Powdery Mildew ◽

Stripe Rust ◽

Puccinia Striiformis ◽

Cyst Nematode ◽

Cereal Cyst Nematode ◽

Thinopyrum Intermedium ◽

Resistant Lines ◽

Multiple Pathogens

Wide hybridization between wheat and wild relatives such as Thinopyrum intermedium is important for broadening genetic diversity and improving disease resistance in wheat. We developed 30 wheat-Th. intermedium derivatives. Here, we report assessments of their resistance to different pathogens including cereal cyst nematode (CCN, Heterodera spp.), Puccinia striiformis causing stripe rust, and Blumeria graminis f. sp. tritici inciting powdery mildew. Under natural field infection, all the wheat-Th. intermedium lines were resistant to at least one of the pathogens, and four lines were resistant to multiple pathogens. Twenty-nine out of 30 tested lines exhibited resistance to H. avenae, a dominant CCN species in wheat fields. Twenty-four lines were resistant to H. filipjevi, an emerging threat to wheat production. Tests of phenotypic responses in the naturally infected field nurseries identified six stripe rust resistant lines and 13 powdery mildew resistant lines. Mitotic observation demonstrated that these newly developed wheat-Th. intermedium derivatives included not only octoploid but also chromosome addition, substitution, and translocation lines. Chromosome compositions of the four lines resistant to multiple pathogens were analyzed by genomic in situ hybridization and fluorescence in situ hybridization. The octoploid lines Zhong 10-68 and Zhong 10-117 carried both intact Th. intermedium chromosomes and translocated chromosomes. Line Zhong 10-149 had 42 wheat chromosomes and two wheat ditelosomes plus a pair of T3BS·J translocated chromosomes. Line Zhong 10-160 carried 41 wheat chromosomes plus one pair of the J genome chromosomes of Th. intermedium. The multiple disease resistant wheat-Th. intermedium derivatives, especially lines with chromosome counts close to common wheat, provide valuable materials for wheat resistance breeding programs.

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The barley immune receptor Mla recognizes multiple pathogens and contributes to host range dynamics

Nature Communications ◽

10.1038/s41467-021-27288-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jan Bettgenhaeuser ◽

Inmaculada Hernández-Pinzón ◽

Andrew M. Dawson ◽

Matthew Gardiner ◽

Phon Green ◽

...

Keyword(s):

Powdery Mildew ◽

Stripe Rust ◽

Resistance Genes ◽

Host Species ◽

Plant Pathogens ◽

Puccinia Striiformis ◽

Species Specificity ◽

Wheat Stripe Rust ◽

Barley Powdery Mildew ◽

Barley Stripe Rust

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.

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High-temperature adult-plant resistance to stripe rust in facultative winter wheat

Crop and Pasture Science ◽

10.1071/cp16073 ◽

2016 ◽

Vol 67 (10) ◽

pp. 1064 ◽

Cited By ~ 2

Author(s):

Beyhan Akin ◽

Xian Ming Chen ◽

Alex Morgunov ◽

Nusret Zencirci ◽

Anmin Wan ◽

...

Keyword(s):

Molecular Markers ◽

High Temperature ◽

Winter Wheat ◽

Stripe Rust ◽

Field Experiments ◽

Puccinia Striiformis ◽

Yellow Rust ◽

Stripe Rust Resistance ◽

Adult Plant ◽

Improvement Program

Stripe (yellow) rust, caused by Puccinia striiformis Westend. f. sp. tritici Erikss., is one of the most damaging diseases in wheat and is especially damaging for winter and facultative wheat. The objective of this study was to understand stripe rust resistance in 100 wheat and facultative wheat entries from the International Winter Wheat Improvement Program by conducting experiments in a greenhouse and in four field environments in Washington State, USA, and by genotyping molecular markers linked to Yr genes. Percentages of entries resistant to the rust races at the seedling stage were: PST-17, 44%; PST-37, 32%; PST-43, 45%; PST-45, 49%; PST-116, 18%; PST-100, 17%; and PST-127, 8%. Molecular markers were positive for genes Yr9, Yr17, and Yr18 and negative for Yr5, Yr10, and Yr15. Yr18 was present in 44 entries (44%). By using the highly virulent races PST-127 and PST-100 under controlled conditions, 16 entries were shown to have high-temperature adult-plant (HTAP) resistance and resistant–moderately resistant field reactions at all four field sites. Resistant entries, especially those with HTAP resistance, were also identified in the field experiments.

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Development of resistance gene analog polymorphism markers for the Yr9 gene resistance to wheat stripe rust

Genome ◽

10.1139/g01-028 ◽

2001 ◽

Vol 44 (4) ◽

pp. 509-516 ◽

Cited By ~ 34

Author(s):

Z X Shi ◽

X M Chen ◽

R F Line ◽

H Leung ◽

C R Wellings

Keyword(s):

Molecular Markers ◽

Resistance Gene ◽

Stripe Rust ◽

Puccinia Striiformis ◽

Resistance Gene Analog ◽

Stripe Rust Resistance ◽

Isogenic Line ◽

Wheat Cultivars ◽

Development Of Resistance ◽

Rye Translocations

The Yr9 gene, which confers resistance to stripe rust caused by Puccinia striiformis f.sp. tritici (P. s. tritici) and originated from rye, is present in many wheat cultivars. To develop molecular markers for Yr9, a Yr9 near-isogenic line, near-isogenic lines with nine other Yr genes, and the recurrent wheat parent 'Avocet Susceptible' were evaluated for resistance in the seedling stage to North American P. s. tritici races under controlled temperature in the greenhouse. The resistance gene analog polymorphism (RGAP) technique was used to identify molecular markers for Yr9. The BC7:F2 and BC7:F3 progeny, which were developed by backcrossing the Yr9 donor wheat cultivar Clement with 'Avocet Susceptible', were evaluated for resistance to stripe rust races. Genomic DNA was extracted from 203 BC7:F2 plants and used for cosegregation analysis. Of 16 RGAP markers confirmed by cosegregation analysis, 4 were coincident with Yr9 and 12 were closely linked to Yr9 with a genetic distance ranging from 1 to 18 cM. Analyses of nulli-tetrasomic 'Chinese Spring' lines with the codominant RGAP marker Xwgp13 confirmed that the markers and Yr9 were located on chromosome 1B. Six wheat cultivars reported to have 1B/1R wheat-rye translocations and, presumably, Yr9, and two rye cultivars were inoculated with four races of P. s. tritici and tested with 9 of the 16 RGAP markers. Results of these tests indicate that 'Clement', 'Aurora', 'Lovrin 10', 'Lovrin 13', and 'Riebesel 47/51' have Yr9 and that 'Weique' does not have Yr9. The genetic information and molecular markers obtained from this study should be useful in cloning Yr9, in identifying germplasm that may have Yr9, and in using marker-assisted selection for combining Yr9 with other stripe rust resistance genes.Key words: molecular markers, Puccinia striiformis f.sp. tritici, resistance gene analog polymorphism, Triticum aestivum.

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Chromosome constitution and origin analysis in three derivatives of Triticum aestivum – Leymus mollis by molecular cytogenetic identification

Genome ◽

10.1139/gen-2014-0161 ◽

2014 ◽

Vol 57 (11/12) ◽

pp. 583-591 ◽

Cited By ~ 13

Author(s):

Xiaofei Yang ◽

Changyou Wang ◽

Chunhuan Chen ◽

Hong Zhang ◽

Zengrong Tian ◽

...

Keyword(s):

Triticum Aestivum ◽

Powdery Mildew ◽

Common Wheat ◽

Stripe Rust ◽

Wheat Breeding ◽

Chromosome Constitution ◽

Disease Resistances ◽

Derivatives Of ◽

Leymus Mollis

Leymus mollis (2n = 4x = 28, NsNsXmXm) is an important tetraploid species in Leymus (Poaceae: Triticeae) and a useful genetic resource for wheat breeding because of the stress tolerance and disease resistance of this species. The development of Triticum aestivum (common wheat) – L. mollis derivatives with desirable genes will provide valuable bridge materials for wheat improvement, especially regarding powdery mildew resistance genes, which are rarely documented in L. mollis. In the present study, three derivatives of common wheat cultivar 7182 and L. mollis, namely M47, M51, and M42, were subjected to chromosomal characterization via cytogenetic identification, the analysis of molecular markers, and genomic in situ hybridization. These derivatives were all morphologically and cytogenetically stable. M47 was highly resistant to powdery mildew and nearly immune to stripe rust at the adult stage, and the chromosome constitution of this derivative can be expressed as 2n = 56 = 42T.a + 14L.m (where T.a = T. aestivum chromosomes; L.m = L. mollis chromosomes). Compared to M47, M42 was also resistant to stripe rust but was susceptible to powdery mildew; the chromosome constitution of M42 was 2n = 54 = 42T.a + 12L.m, in which a pair of homoeologous group 7 L.m chromosomes was eliminated. Finally, M51 was susceptible to powdery mildew and stripe rust and had a chromosome constitution of 2n = 48 = 42T.a + 6L.m, in which four pairs of L.m chromosomes from homoeologous groups 2, 4, 5, and 7 were eliminated. The differing disease resistances of the three derivatives are discussed in this report in the context of their chromosomal variations; this information can thus contribute to breeding disease resistant wheat with the potential for applying these derivatives as useful bridge materials.

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Molecular cytogenetics and St-chromosome-specific molecular markers development of novel stripe rust resistant wheat–Thinopyrum intermedium as well as wheat–Thinopyrum ponticum substitution lines

10.21203/rs.3.rs-911109/v1 ◽

2021 ◽

Author(s):

Siwen Wang ◽

Changyou Wang ◽

Xianbo Feng ◽

Jixin Zhao ◽

Pingchuan Deng ◽

...

Keyword(s):

Molecular Marker ◽

Stripe Rust ◽

Rust Resistance ◽

Snp Array ◽

Kernel Weight ◽

Stripe Rust Resistance ◽

Substitution Lines ◽

Fish Genome ◽

Thinopyrum Ponticum

Abstract Background Owing to the excellent resistance to abiotic and biotic stress, Thionpyrum intermedium (2n = 6x = 42, JJJsJsStSt) and Thinopyrum ponticum (2n = 10x = 70) are both widely utilized in wheat germplasm innovation programs. Disomic substitution lines (DSLs) carrying one pair of alien chromosomes are valuable bridge materials for novel genes transmission, FISH karyotype construction and specific molecular marker development. Results Six wheat–Thinopyrum DSLs derived from crosses between Abbondanza nullisomic lines (2n = 40) and two octoploid Trititrigia lines (2n = 8x = 56), were characterized by a sequential fluorescence in situ hybridization (FISH)–genome in situ hybridization (GISH), a multicolor GISH (mc-GISH), and an analysis of wheat 15K SNP array combined with molecular marker selection. ES-9 (DS2St (2A)) and ES-10 (DS3St (3D)) are wheat–Th. ponticum DSLs, while ES-23 (DS2St (2A)), ES-24 (DS3St (3D)), ES-25(DS2St (2B)), and ES-26 (DS2St (2D)) are wheat–Th. intermedium DSLs. ES-9, ES-23, ES-25 and ES-26 conferred higher thousand-kernel weight and stripe rust resistance at adult stages, while ES-10 and ES-24 performed highly resistant to stripe rust at all stages. Furthermore, cytological analysis showed that the alien chromosomes (2St/3St) belonging to the same homoeologous group derived from different donors carried the same FISH karyotype and could normally form a bivalent. Based on specific-locus amplified fragment sequencing (SLAF-seq), two 2St-chromosome-specific markers (PTH-005 and PTH-013) and two 3St-chromosome-specific markers (PTH-113 and PTH-135) were developed. Conclusions The six wheat–Thinopyrum disomic substitution lines conferring stripe rust resistance will be used as bridging parents for valuable resistant genes transmission. And the utility of PTH-113 and PTH-135 in a BC1F2 population showed the newly developed markers could be useful tools for efficient identification of St chromosomes in a common wheat background.

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Characterization of New Wheat-Dasypyrum breviaristatum Introgression Lines with Superior Gene(s) for Spike Length and Stripe Rust Resistance

Cytogenetic and Genome Research ◽

10.1159/000493562 ◽

2018 ◽

Vol 156 (2) ◽

pp. 117-125 ◽

Cited By ~ 1

Author(s):

Hongjin Wang ◽

Zhihui Yu ◽

Bin Li ◽

Tao Lang ◽

Guangrong Li ◽

...

Keyword(s):

Molecular Markers ◽

Stripe Rust ◽

Rust Resistance ◽

Field Evaluation ◽

Spike Length ◽

Stripe Rust Resistance ◽

Stripe Rust Resistance Gene ◽

Fraction Length ◽

Dasypyrum Breviaristatum

Dasypyrum breviaristatum (genome VbVb) contains potentially important traits for commercial wheat production. Chromosome 2Vb of D. breviaristatum carries several desirable agronomic characters, including long spike length as well as enhanced resistance to stripe rust, which are expressed in a common wheat background. In this study, wheat-D. breviaristatum 2Vb deletion lines were produced and identified by fluorescence in situ hybridization (FISH), and 74 molecular markers specific to D. breviaristatum chromosome 2Vb were physically localized in 4 distinct chromosomal regions. New wheat-D. breviaristatum 2Vb translocation lines were also characterized by FISH. The breakpoint of the translocation T3AS.3AL-2VbS was determined by physically mapped molecular markers. Field evaluation revealed that genes affecting plant height and spike length are located on fraction length (FL) 0.65-1.00 of 2VbS, while the stripe rust resistance gene(s) are located on FL 0.40-1.00 of D. breviaristatum chromosome 2VbL. The newly characterized wheat-Dasypyrum chromosomal introgressions are of potential value for the improvement of the yield and disease resistance of wheat.

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Characterization and Evaluation of Resistance to Powdery Mildew of Wheat–Aegilops geniculata Roth 7Mg (7A) Alien Disomic Substitution Line W16998

International Journal of Molecular Sciences ◽

10.3390/ijms21051861 ◽

2020 ◽

Vol 21 (5) ◽

pp. 1861

Author(s):

Yajuan Wang ◽

Deyu Long ◽

Yanzhen Wang ◽

Changyou Wang ◽

Xinlun Liu ◽

...

Keyword(s):

In Situ Hybridization ◽

Powdery Mildew ◽

Common Wheat ◽

Agronomic Traits ◽

Genomic In Situ Hybridization ◽

Substitution Line ◽

Aegilops Geniculata ◽

The Common ◽

Sequential Fish

Aegilops geniculata Roth has been used as a donor of disease-resistance genes, to enrich the gene pool for wheat (Triticum aestivum) improvement through distant hybridization. In this study, the wheat–Ae. geniculata alien disomic substitution line W16998 was obtained from the BC1F8 progeny of a cross between the common wheat ‘Chinese Spring’ (CS) and Ae. geniculata Roth (serial number: SY159//CS). This line was identified using cytogenetic techniques, analysis of genomic in situ hybridization (GISH), functional molecular markers (Expressed sequence tag-sequence-tagged site (EST–STS) and PCR-based landmark unique gene (PLUG), fluorescence in situ hybridization (FISH), sequential fluorescence in situ hybridization–genomic in situ hybridization (sequential FISH–GISH), and assessment of agronomic traits and powdery mildew resistance. During the anaphase of meiosis, these were evenly distributed on both sides of the equatorial plate, and they exhibited high cytological stability during the meiotic metaphase and anaphase. GISH analysis indicated that W16998 contained a pair of Ae. geniculata alien chromosomes and 40 common wheat chromosomes. One EST–STS marker and seven PLUG marker results showed that the introduced chromosomes of Ae. geniculata belonged to homoeologous group 7. Nullisomic–tetrasomic analyses suggested that the common wheat chromosome, 7A, was absent in W16998. FISH and sequential FISH–GISH analyses confirmed that the introduced Ae. geniculata chromosome was 7Mg. Therefore, W16998 was a wheat–Ae. geniculata 7Mg (7A) alien disomic substitution line. Inoculation of isolate E09 (Blumeria graminis f. sp. tritici) in the seedling stage showed that SY159 and W16998 were resistant to powdery mildew, indeed nearly immune, whereas CS was highly susceptible. Compared to CS, W16998 exhibited increased grain weight and more spikelets, and a greater number of superior agronomic traits. Consequently, W16998 was potentially useful. Germplasms transfer new disease-resistance genes and prominent agronomic traits into common wheat, giving the latter some fine properties for breeding.

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