scholarly journals Lessons from a Phenotyping Center Revealed by the Genome-Guided Mapping of Powdery Mildew Resistance Loci

2016 ◽  
Vol 106 (10) ◽  
pp. 1159-1169 ◽  
Author(s):  
Lance Cadle-Davidson ◽  
David Gadoury ◽  
Jonathan Fresnedo-Ramírez ◽  
Shanshan Yang ◽  
Paola Barba ◽  
...  
Keyword(s):  
High Resolution ◽  
Powdery Mildew ◽  
Host Resistance ◽  
Powdery Mildew Resistance ◽  
Natural Infection ◽  
Genotyping By Sequencing ◽  
Developmentally Regulated ◽  
Mildew Resistance ◽  
Powdery Mildews ◽  
Trait Locus

The genomics era brought unprecedented opportunities for genetic analysis of host resistance, but it came with the challenge that accurate and reproducible phenotypes are needed so that genomic results appropriately reflect biology. Phenotyping host resistance by natural infection in the field can produce variable results due to the uncontrolled environment, uneven distribution and genetics of the pathogen, and developmentally regulated resistance among other factors. To address these challenges, we developed highly controlled, standardized methodologies for phenotyping powdery mildew resistance in the context of a phenotyping center, receiving samples of up to 140 grapevine progeny per F1 family. We applied these methodologies to F1 families segregating for REN1- or REN2-mediated resistance and validated that some but not all bioassays identified the REN1 or REN2 locus. A point-intercept method (hyphal transects) to quantify colony density objectively at 8 or 9 days postinoculation proved to be the phenotypic response most reproducibly predicted by these resistance loci. Quantitative trait locus (QTL) mapping with genotyping-by-sequencing maps defined the REN1 and REN2 loci at relatively high resolution. In the reference PN40024 genome under each QTL, nucleotide-binding site−leucine-rich repeat candidate resistance genes were identified—one gene for REN1 and two genes for REN2. The methods described here for centralized resistance phenotyping and high-resolution genetic mapping can inform strategies for breeding resistance to powdery mildews and other pathogens on diverse, highly heterozygous hosts.

scholarly journals MILDEW LOCUS O Mutation Does Not Affect Resistance to Grain Infections with Fusarium spp. and Ramularia collo-cygni

2015 ◽  
Vol 105 (9) ◽  
pp. 1214-1219 ◽  
Author(s):  
Katharina Hofer ◽  
Andrea Linkmeyer ◽  
Katharina Textor ◽  
Ralph Hückelhoven ◽  
Michael Hess
Keyword(s):  
Cell Death ◽  
Powdery Mildew ◽  
Fungal Pathogens ◽  
Powdery Mildew Resistance ◽  
Natural Infection ◽  
Spring Barley ◽  
Susceptibility Gene ◽  
Fusarium Spp ◽  
Mildew Resistance ◽  
Barley Powdery Mildew

MILDEW LOCUS O defines a major susceptibility gene for powdery mildew, and recessive mlo resistance alleles are widely used in breeding for powdery mildew resistance in spring barley. Barley powdery mildew resistance, which is conferred by mlo genes, is considered to be costly in terms of spontaneous defense reactions and enhanced susceptibility to cell-death-inducing pathogens. We assessed fungal infestation of barley (Hordeum vulgare) grain by measuring fungal DNA after natural infection with Fusarium spp. and Ramularia collo-cygni or after inoculation with Fusarium spp. in the field. Powdery-mildew-resistant mlo5 genotypes did not show enhanced Fusarium spp. or R. collo-cygni DNA content of grain over four consecutive years. Data add to our understanding of pleiotropic effects of mlo-mediated powdery mildew resistance and contributes to the discussion of whether or not application of barley mlo mutations may support pathogenesis of cell-death-inducing fungal pathogens under field conditions.

scholarly journals Grapevine powdery mildew resistance and susceptibility loci identified on a high-resolution SNP map

2013 ◽  
Vol 127 (1) ◽  
pp. 73-84 ◽  
Author(s):  
Paola Barba ◽  
Lance Cadle-Davidson ◽  
James Harriman ◽  
Jeffrey C. Glaubitz ◽  
Siraprapa Brooks ◽  
...  
Keyword(s):  
High Resolution ◽  
Powdery Mildew ◽  
Powdery Mildew Resistance ◽  
Susceptibility Loci ◽  
Mildew Resistance ◽  
Grapevine Powdery Mildew ◽  
Snp Map

scholarly journals Genotyping by Sequencing-Based Discovery of SNP Markers and Construction of Linkage Map from F5 Population of Pepper with Contrasting Powdery Mildew Resistance Trait

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Abinaya Manivannan ◽  
Sena Choi ◽  
Tae-Hwan Jun ◽  
Eun-Young Yang ◽  
Jin-Hee Kim ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Linkage Map ◽  
Powdery Mildew Resistance ◽  
Genotyping By Sequencing ◽  
Snp Markers ◽  
Read Mapping ◽  
Single Nucleotide ◽  
Mildew Resistance ◽  
Polymorphic Snps ◽  
Resistance Trait

Powdery mildew (PM) is a common fungal disease infecting pepper plants worldwide. Molecular breeding of pepper cultivars with powdery mildew resistance is desirable for the economic improvement of pepper cultivation. In the present study, 188 F5 population derived from AR1 (PM resistant) and TF68 (PM sensitive) parents were subjected to high-throughput genotyping by sequencing (GBS) for the identification of single nucleotide polymorphism (SNP) markers. Further, the identified SNP markers were utilized for the construction of genetic linkage map and QTL analysis. Overall read mapping percentage of 87.29% was achieved in this study with the total length of mapped region ranging from 2,956,730 to 25,537,525 bp. A total of 41,111 polymorphic SNPs were identified, and a final of 1,841 SNPs were filtered for the construction of a linkage map. A total of 12 linkage groups were constructed corresponding to each chromosome with 1,308 SNP markers with the map length of 2506.8 cM. Further, two QTLs such as Pm-2.1 and Pm-5.1 were identified in chromosomes 2 and 5, respectively, for the PM resistance. Overall, the outcomes of the present endeavor can be utilized for the marker-assisted selection of pepper with powdery mildew-resistant trait.

scholarly journals New Pathotype Nomenclature for Better Characterisation the Virulence and Diversity of Blumeria graminis f.sp. avenae Populations

Agronomy ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1852
Author(s):  
Sylwia Okoń ◽  
Magdalena Cieplak ◽  
Adam Kuzdraliński ◽  
Tomasz Ociepa
Keyword(s):  
Powdery Mildew ◽  
Resistance Genes ◽  
Host Resistance ◽  
Powdery Mildew Resistance ◽  
Blumeria Graminis ◽  
Sources Of Resistance ◽  
Mildew Resistance ◽  
Differential Set ◽  
Letter Code ◽  
First Time

Fungal cereal pathogens, including Blumeria graminis f.sp. avenae, have the ability to adapt to specific conditions, which in turn leads to overcoming host resistance. An important aspect is the standardized way of characterizing the races and pathotypes of the pathogen. In the presented work, for the first time it was proposed to use a unified letter code that allows describing the pathotypes of B. graminis f.sp. avenae. The set of 14 oat genotypes were used as a differential set. This set included genotypes having so far described powdery mildew resistance genes Pm1–Pm11, and two genotypes (A. sterilis and A. strigosa) with effective sources of resistance to Bga. Based on the analysis of 160 Bga isolates collected in 2016–2019 from 4 locations in Poland, the most numerous was the TBBB pathotype, represented by 30% of the tested isolates. It was present in all analyzed populations. Subsequently, 8.1% and 6.3% of the isolates represented the TBCB and RBBB pathotypes, respectively.

scholarly journals High Resolution Genetic and Physical Mapping of a Major Powdery Mildew Resistance Locus in Barley

2019 ◽  
Vol 10 ◽  
Author(s):  
Parastoo Hoseinzadeh ◽  
Ruonan Zhou ◽  
Martin Mascher ◽  
Axel Himmelbach ◽  
Rients E. Niks ◽  
...  
Keyword(s):  
High Resolution ◽  
Powdery Mildew ◽  
Physical Mapping ◽  
Powdery Mildew Resistance ◽  
Resistance Locus ◽  
Mildew Resistance ◽  
Genetic And Physical Mapping

scholarly journals Genetic Mapping of Powdery Mildew Resistance Genes in Wheat Landrace ‘Guizi 1’ Using Genotyping-By-Sequencing

2021 ◽  
Author(s):  
Luhua Li ◽  
Xicui Yang ◽  
Zhongni Wang ◽  
Mingjian Ren ◽  
Chang An ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Resistance Genes ◽  
Quantitative Trait ◽  
Powdery Mildew Resistance ◽  
Dominant Gene ◽  
Genotyping By Sequencing ◽  
Snp Markers ◽  
Phenotypic Variance ◽  
Nucleotide Polymorphisms ◽  
Mildew Resistance

Abstract Wheat powdery mildew (Pm), caused by Blumeria graminis f. sp. tritici (Bgt), is a destructive disease of wheat (Triticum aestivum L.) worldwide that causes severe yield losses. Resistant wheat cultivars easily lose effective resistance against newly emerged Bgt strains; therefore, identifying new resistance genes is necessary for breeding resistant cultivars. ‘Guizi 1’ is a Chinese wheat cultivar with effective moderate and stable resistance against powdery mildew. A genetic analysis indicated that powdery mildew resistance in ‘Guizi 1’ was controlled by a single dominant gene, designated PmGZ1. In total, 110 F2 individual plants and the 2 parents were used for genotyping-by-sequencing, which produced 23,134 high-quality single-nucleotide polymorphisms (SNPs). The SNP distributions on the 21 chromosomes ranged from 134 on chromosome 6D to 6,288 on chromosome 3B. Chromosome 6A has 1,866 SNPs, among which 16 are located in a physical region between positions 307,802,221 and 309,885,836 in an approximate 2.3-cM region, which possessed the greatest SNP density. The average map distance between SNP markers was 0.1 cM. A quantitative trait locus with a significant epistatic effect on powdery mildew resistance was mapped to Chromosome 6A. The LOD value of PmGZ1 reached 34.8, and PmGZ1 was located within the confidence interval marked by chr6a-307802221 and chr6a-309885836. The phenotypic variance explained by PmGZ1 was 74.7%. Four candidate genes (two each encoding TaAP2-A and actin proteins) were annotated as resistance genes. The present results provide valuable information for wheat genetic improvement, quantitative trait loci fine mapping, and candidate gene validation.

Sign in / Sign up

Export Citation Format

Share Document