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The abovementioned results imply that the silent genetic loci like I Pm41b i are a valuable resource of genetic variation in the wheat genome and therefore could be potentially utilized to enrich the genetic diversity in wheat breeding. Keywords: Pm41; allelic variation; genetic diversity; transposon; gene silencing EN Pm41 allelic variation genetic diversity transposon gene silencing 2039 2041 3 11/01/22 20221101 NES 221101 Common wheat ( I Triticum aestivum i . [Extracted from the article]

Summary: Powdery mildew poses severe threats to wheat production. The most sustainable way to control this disease is through planting resistant cultivars.We report the map‐based cloning of the powdery mildew resistance allele Pm5e from a Chinese wheat landrace. We applied a two‐step bulked segregant RNA sequencing (BSR‐Seq) approach in developing tightly linked or co‐segregating markers to Pm5e. The first BSR‐Seq used phenotypically contrasting bulks of recombinant inbred lines (RILs) to identify Pm5e‐linked markers. The second BSR‐Seq utilized bulks of genetic recombinants screened from a fine‐mapping population to precisely quantify the associated genomic variation in the mapping interval, and identified the Pm5e candidate genes.The function of Pm5e was validated by transgenic assay, loss‐of‐function mutants and haplotype association analysis. Pm5e encodes a nucleotide‐binding domain leucine‐rich‐repeat‐containing (NLR) protein. A rare nonsynonymous single nucleotide variant (SNV) within the C‐terminal leucine rich repeat (LRR) domain is responsible for the gain of powdery mildew resistance function of Pm5e, an allele endemic to wheat landraces of Shaanxi province of China.Results from this study demonstrate the value of landraces in discovering useful genes for modern wheat breeding. The key SNV associated with powdery mildew resistance will be useful for marker‐assisted selection of Pm5e in wheat breeding programs. [ABSTRACT FROM AUTHOR]

Summary: Powdery mildew, a fungal disease caused by Blumeria graminis f. sp. tritici (Bgt), has a serious impact on wheat production. Loss of resistance in cultivars prompts a continuing search for new sources of resistance.Wild emmer wheat (Triticum turgidum ssp. dicoccoides, WEW), the progenitor of both modern tetraploid and hexaploid wheats, harbors many powdery mildew resistance genes. We report here the positional cloning and functional characterization of Pm41, a powdery mildew resistance gene derived from WEW, which encodes a coiled‐coil, nucleotide‐binding site and leucine‐rich repeat protein (CNL). Mutagenesis and stable genetic transformation confirmed the function of Pm41 against Bgt infection in wheat.We demonstrated that Pm41 was present at a very low frequency (1.81%) only in southern WEW populations. It was absent in other WEW populations, domesticated emmer, durum, and common wheat, suggesting that the ancestral Pm41 was restricted to its place of origin and was not incorporated into domesticated wheat.Our findings emphasize the importance of conservation and exploitation of the primary WEW gene pool, as a valuable resource for discovery of resistance genes for improvement of modern wheat cultivars. [ABSTRACT FROM AUTHOR]

Bulked segregant CGT-Seq-facilitated map-based cloning of a powdery mildew resistance gene originating from wild emmer wheat (Triticum dicoccoides) In this study, we cloned the powdery mildew resistance allele I MlWE18 i ( I NLR SP WE18 sp i ) whose locus is not present in the wheat reference genomes using a combined BSA and CGT-seq strategies. Most of the cloned wheat disease resistance genes are NLRs that tend to be PAVs between the resistance and susceptible genotypes, especially the genes derived from wild relatives (Li I et al i ., 2020; Walkowiak I et al i ., 2020). Keywords: BSA; ChIP-Seq; NLR; PAV EN BSA ChIP-Seq NLR PAV 1288 1290 3 07/28/21 20210701 NES 210701 Powdery mildew, caused by I Blumeria graminis i f. sp. I tritici i ( I Bgt i ), is a widely occurring foliar disease of wheat worldwide. [Extracted from the article]