Molecular Characterization of a Powdery Mildew Resistance Gene in Wheat Cultivar Suwon 92

Powdery mildew, caused by Blumeria graminis f. sp tritici, is an important foliar disease of wheat worldwide. Pyramiding race-specific genes into a single cultivar and combining race-specific resistance genes with durable resistance genes are the preferred strategies to improve the durability of powdery mildew resistance. The objectives of this study were to characterize a powdery mildew resistance gene in Suwon 92 and identify gene-specific or tightly linked molecular markers for marker-assisted selection (MAS). A population of recombinant inbred lines (RILs) was derived by single seed descent from a cross between Suwon 92 and a susceptible cultivar, CI 13227. The RILs were screened for adult-plant infection type of powdery mildew and characterized with amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers. The linked markers explained 41.3 to 69.2% of the phenotypic variances measured in 2 years. A morphological marker, hairy glume, was also associated with powdery mildew resistance in Suwon 92, and explained 43 to 51% of the phenotypic variance. The powdery mildew resistance gene in Suwon 92 was located on the short arm of chromosome 1A where Pm3 was located. Two gene-specific markers were developed based on the sequence of the cloned Pm3b gene. These two markers, which were mapped at the same locus in the peak region of the LOD score for the RIL population, explained most of the phenotypic variance for powdery mildew resistance in the RIL population. The powdery mildew resistance in Suwon 92 is most likely conditioned by the Pm3 locus. The gene markers developed herein can be directly used for MAS of some of the Pm3 alleles in breeding programs.

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Physical Mapping of Pm57, a Powdery Mildew Resistance Gene Derived from Aegilops searsii

10.20944/preprints201912.0322.v1 ◽

2019 ◽

Author(s):

Zhenjie Dong ◽

Xiubin Tian ◽

Chao Ma ◽

Qing Xia ◽

Beilin Wang ◽

...

Keyword(s):

Molecular Markers ◽

Powdery Mildew ◽

Binding Site ◽

Resistance Gene ◽

Resistance Genes ◽

Powdery Mildew Resistance ◽

Nucleotide Binding ◽

Leucine Rich Repeat ◽

Powdery Mildew Resistance Gene ◽

Mildew Resistance

Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is one of many severe diseases that threaten bread wheat (Triticum aestivum L.) yield and quality worldwide. The discovery and deployment of powdery mildew resistance genes (Pm) can prevent this disease epidemic in wheat. In a previous study, we transferred the powdery mildew resistance gene Pm57 from Aegilops searsii into common wheat and cytogenetically mapped the gene in a chromosome region with the fraction length (FL) 0.75-0.87, which represents 12% of 2Ss#1 segment on the long arm of chromosome 2Ss#1. In this study, we performed RNA-Seq on three infected and mock-infected wheat-Ae. searsii 2Ss#1 introgression lines with Bgt-isolates inoculation at 0, 12, 24, and 48 hours after inoculation. Then we designed 79 molecular markers based on transcriptome sequences and physically mapped them to Ae. searsii chromosome 2Ss#1- in seven intervals. We used these markers to identify 46 wheat-Ae. searsii 2Ss#1 recombinants induced by ph1b, a deletion mutant of pairing homoelogous (Ph) genes. Analysis of the 46 ph1b-induced 2Ss#1L recombinants with different Bgt-responses using 28 2Ss#1L-specific molecular markers in the interval FL0.72-0.87 where Pm57 is located, and the flanking intervals, we physically mapped Pm57 gene on the long arm of 2Ss#1 in a 5.13 Mb genomic region, which was flanked by markers X67593 (773.72 Mb) and X62492 (778.85 Mb). By comparative synteny analysis of the corresponding region on chromosome 2B in Chinese spring (T. aestivum L.) with other model species we identified ten genes that are putative plant defense-related (R) genes which includes six coiled-coil nucleotide-binding site-leucine-rich repeat (CNL), three nucleotide-binding site-leucine-rich repeat (NL) and a leucine-rich receptor-like repeat (RLP) encoding proteins. This study will lay a foundation for further cloning of Pm57, and benefit the understanding of interactions between resistance genes of wheat and powdery mildew pathogens.

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Physical Mapping of Pm57, a Powdery Mildew Resistance Gene Derived from Aegilops searsii

International Journal of Molecular Sciences ◽

10.3390/ijms21010322 ◽

2020 ◽

Vol 21 (1) ◽

pp. 322 ◽

Cited By ~ 1

Author(s):

Zhenjie Dong ◽

Xiubin Tian ◽

Chao Ma ◽

Qing Xia ◽

Beilin Wang ◽

...

Keyword(s):

Powdery Mildew ◽

Binding Site ◽

Resistance Gene ◽

Resistance Genes ◽

Powdery Mildew Resistance ◽

Nucleotide Binding ◽

Nucleotide Binding Site ◽

Leucine Rich Repeat ◽

Powdery Mildew Resistance Gene ◽

Mildew Resistance

Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is one of many severe diseases that threaten bread wheat (Triticum aestivum L.) yield and quality worldwide. The discovery and deployment of powdery mildew resistance genes (Pm) can prevent this disease epidemic in wheat. In a previous study, we transferred the powdery mildew resistance gene Pm57 from Aegilops searsii into common wheat and cytogenetically mapped the gene in a chromosome region with the fraction length (FL) 0.75–0.87, which represents 12% segment of the long arm of chromosome 2Ss#1. In this study, we performed RNA-seq using RNA extracted from leaf samples of three infected and mock-infected wheat-Ae. searsii 2Ss#1 introgression lines at 0, 12, 24, and 48 h after inoculation with Bgt isolates. Then we designed 79 molecular markers based on transcriptome sequences and physically mapped them to Ae. searsii chromosome 2Ss#1- in seven intervals. We used these markers to identify 46 wheat-Ae. searsii 2Ss#1 recombinants induced by ph1b, a deletion mutant of pairing homologous (Ph) genes. After analyzing the 46 ph1b-induced 2Ss#1L recombinants in the region where Pm57 is located with different Bgt-responses, we physically mapped Pm57 gene on the long arm of 2Ss#1 in a 5.13 Mb genomic region, which was flanked by markers X67593 (773.72 Mb) and X62492 (778.85 Mb). By comparative synteny analysis of the corresponding region on chromosome 2B in Chinese Spring (T. aestivum L.) with other model species, we identified ten genes that are putative plant defense-related (R) genes which includes six coiled-coil nucleotide-binding site-leucine-rich repeat (CNL), three nucleotide-binding site-leucine-rich repeat (NL) and a leucine-rich receptor-like repeat (RLP) encoding proteins. This study will lay a foundation for cloning of Pm57, and benefit the understanding of interactions between resistance genes of wheat and powdery mildew pathogens.

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Microsatellite markers linked to 2 powdery mildew resistance genes introgressed from Triticum carthlicum accession PS5 into common wheat

Genome ◽

10.1139/g05-016 ◽

2005 ◽

Vol 48 (4) ◽

pp. 585-590 ◽

Cited By ~ 74

Author(s):

Zhendong Zhu ◽

Ronghua Zhou ◽

Xiuying Kong ◽

Yuchen Dong ◽

Jizeng Jia

Keyword(s):

Powdery Mildew ◽

Microsatellite Markers ◽

Resistance Gene ◽

Common Wheat ◽

Resistance Genes ◽

Powdery Mildew Resistance ◽

Wheat Chromosome ◽

The Other ◽

Powdery Mildew Resistance Gene ◽

Mildew Resistance

Two dominant powdery mildew resistance genes introduced from Triticum carthlicum accession PS5 to common wheat were identified and tagged using microsatellite markers. The gene designated PmPS5A was placed on wheat chromosome 2AL and linked to the microsatellite marker Xgwm356 at a genetic distance of 10.2 cM. Based on the information of its origin, chromosome location, and reactions to 5 powdery mildew isolates, this gene could be a member of the complex Pm4 locus. The 2nd gene designated PmPS5B was located on wheat chromosome 2BL with 3 microsatellite markers mapping proximally to the gene: Xwmc317 at 1.1 cM; Xgwm111 at 2.2 cM; and Xgwm382 at 4.0 cM; and 1 marker, Xgwm526, mapping distally to the gene at a distance of 18.1 cM. Since this gene showed no linkage to the other 2 known powdery mildew resistance genes on wheat chromosome 2B, Pm6 and Pm26, we believe it is a novel powdery mildew resistance gene and propose to designate this gene as Pm33.Key words: powdery mildew, resistance gene, microsatellite, Triticum carthlicum, wheat.

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