Genomic Regions Associated with Virulence in Pyrenophora teres f. teres Identified by Genome-Wide Association Analysis and Biparental Mapping

Net form net blotch (NFNB), caused by the fungal pathogen Pyrenophora teres f. teres, is an important foliar disease present in all barley-producing regions of the world. This fungus is a hemibiotrophic and heterothallic ascomycete, where sexual recombination can lead to changes in disease expression in the host. Knowledge of the genetic architecture and genes involved in virulence is vital to increase the durability of NFNB resistance in barley cultivars. We used a genome-wide association mapping approach to characterize P. teres f. teres genomic regions associated with virulence in Australian barley cultivars. One hundred eighty-eight P. teres f. teres isolates collected across five Australian states were genotyped using Diversity Arrays Technology sequence markers and phenotyped across 20 different barley genotypes. Association mapping identified 14 different genomic regions associated with virulence, with the majority located on P. teres f. teres chromosomes 3 and 5 and one each present on chromosomes 1, 6, and 9. Four of the regions identified were confirmed by quantitative trait loci (QTL) mapping. The QTL regions are discussed in the context of their genomic architecture together with examination of their gene contents, which identified 20 predicted effectors. The number of QTL shown in this study at the population level clearly illustrates a complex genetic basis of P. teres f. teres virulence compared with pure necrotrophs, such as the wheat pathogens Parastagonospora nodorum and Parastagonospora tritici-repentis.

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Genome-Wide Association Mapping for Heat and Drought Adaptive Traits in Pea

Genes ◽

10.3390/genes12121897 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1897

Author(s):

Endale G. Tafesse ◽

Krishna K. Gali ◽

V. B. Reddy Lachagari ◽

Rosalind Bueckert ◽

Thomas D. Warkentin

Keyword(s):

Association Mapping ◽

Candidate Genes ◽

Vegetation Index ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Nucleotide Polymorphisms ◽

Adaptive Traits ◽

Flowering Duration ◽

Genome Wide ◽

A Genome

Heat and drought, individually or in combination, limit pea productivity. Fortunately, substantial genetic diversity exists in pea germplasm for traits related to abiotic stress resistance. Understanding the genetic basis of resistance could accelerate the development of stress-adaptive cultivars. We conducted a genome-wide association study (GWAS) in pea on six stress-adaptive traits with the aim to detect the genetic regions controlling these traits. One hundred and thirty-five genetically diverse pea accessions were phenotyped in field studies across three or five environments under stress and control conditions. To determine marker trait associations (MTAs), a total of 16,877 valuable single nucleotide polymorphisms (SNPs) were used in association analysis. Association mapping detected 15 MTAs that were significantly (p ≤ 0.0005) associated with the six stress-adaptive traits averaged across all environments and consistent in multiple individual environments. The identified MTAs were four for lamina wax, three for petiole wax, three for stem thickness, two for the flowering duration, one for the normalized difference vegetation index (NDVI), and two for the normalized pigment and chlorophyll index (NPCI). Sixteen candidate genes were identified within a 15 kb distance from either side of the markers. The detected MTAs and candidate genes have prospective use towards selecting stress-hardy pea cultivars in marker-assisted selection.

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Genome-Wide Association Study and Selection Signatures Detect Genomic Regions Associated with Seed Yield and Oil Quality in Flax

International Journal of Molecular Sciences ◽

10.3390/ijms19082303 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2303 ◽

Cited By ~ 18

Author(s):

Frank You ◽

Jin Xiao ◽

Pingchuan Li ◽

Zhen Yao ◽

Gaofeng Jia ◽

...

Keyword(s):

Association Study ◽

Seed Yield ◽

Phenotypic Variation ◽

Genome Wide Association Study ◽

Oil Quality ◽

Genome Wide Association ◽

Selection Signatures ◽

Genome Wide ◽

A Genome ◽

Genomic Regions

A genome-wide association study (GWAS) was performed on a set of 260 lines which belong to three different bi-parental flax mapping populations. These lines were sequenced to an averaged genome coverage of 19× using the Illumina Hi-Seq platform. Phenotypic data for 11 seed yield and oil quality traits were collected in eight year/location environments. A total of 17,288 single nucleotide polymorphisms were identified, which explained more than 80% of the phenotypic variation for days to maturity (DTM), iodine value (IOD), palmitic (PAL), stearic, linoleic (LIO) and linolenic (LIN) acid contents. Twenty-three unique genomic regions associated with 33 quantitative trait loci (QTL) for the studied traits were detected, thereby validating four genomic regions previously identified. The 33 QTL explained 48–73% of the phenotypic variation for oil content, IOD, PAL, LIO and LIN but only 8–14% for plant height, DTM and seed yield. A genome-wide selective sweep scan for selection signatures detected 114 genomic regions that accounted for 7.82% of the flax pseudomolecule and overlapped with the 11 GWAS-detected genomic regions associated with 18 QTL for 11 traits. The results demonstrate the utility of GWAS combined with selection signatures for dissection of the genetic structure of traits and for pinpointing genomic regions for breeding improvement.

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P1.08 Identification of Three Genomic Regions with Multiple Consecutive Prostate Cancer Susceptibility Loci Through a Genome-Wide Association Study in ARAB Population

Annals of Oncology ◽

10.1016/s0923-7534(20)31299-0 ◽

2012 ◽

Vol 23 ◽

pp. v14

Author(s):

L. Chouchane ◽

S. Shan ◽

K. al-Rumaihi ◽

I. al-Bozom ◽

S. al-Said ◽

...

Keyword(s):

Prostate Cancer ◽

Genome Wide Association Study ◽

Cancer Susceptibility ◽

Genome Wide Association ◽

Susceptibility Loci ◽

Arab Population ◽

Prostate Cancer Susceptibility ◽

Genome Wide ◽

A Genome ◽

Genomic Regions

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Genome-wide association mapping of genomic regions associated with phenotypic traits in Canadian western spring wheat

Molecular Breeding ◽

10.1007/s11032-017-0741-6 ◽

2017 ◽

Vol 37 (11) ◽

Cited By ~ 7

Author(s):

Hua Chen ◽

Kassa Semagn ◽

Muhammad Iqbal ◽

Neshat Pazooki Moakhar ◽

Teketel Haile ◽

...

Keyword(s):

Association Mapping ◽

Spring Wheat ◽

Genome Wide Association ◽

Phenotypic Traits ◽

Genome Wide ◽

Genomic Regions

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Erratum to: Genome-wide association mapping of agronomic and morphologic traits in highly structured populations of barley cultivars

Theoretical and Applied Genetics ◽

10.1007/s00122-011-1771-9 ◽

2011 ◽

Vol 124 (2) ◽

pp. 247-247

Author(s):

Minghui Wang ◽

Ning Jiang ◽

Tianye Jia ◽

Lindsey Leach ◽

James Cockram ◽

...

Keyword(s):

Association Mapping ◽

Structured Populations ◽

Genome Wide Association ◽

Barley Cultivars ◽

Genome Wide

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A Genome-Wide Association Study Identifies SNP Markers for Virulence in Magnaporthe oryzae Isolates from Sub-Saharan Africa

10.1101/418509 ◽

2018 ◽

Cited By ~ 1

Author(s):

Veena Devi Ganeshan ◽

Stephen O. Opiyo ◽

Samuel K. Mutiga ◽

Felix Rotich ◽

David M. Thuranira ◽

...

Keyword(s):

Association Study ◽

Magnaporthe Oryzae ◽

Genome Wide Association Study ◽

Significant Snps ◽

Sub Saharan Africa ◽

Genome Wide Association ◽

Genome Wide ◽

A Genome ◽

Sub Saharan ◽

Genomic Regions

ABSTRACTThe fungal phytopathogen Magnaporthe oryzae causes blast disease in cereals such as rice and finger millet worldwide. In this study, we assessed genetic diversity of 160 isolates from nine sub-Saharan Africa (SSA) and other principal rice producing countries and conducted a genome-wide association study (GWAS) to identify the genomic regions associated with virulence of M. oryzae. GBS of isolates provided a large and high-quality 617K single nucleotide polymorphism (SNP) dataset. Disease ratings for each isolate was obtained by inoculating them onto differential lines and locally-adapted rice cultivars. Genome-wide association studies were conducted using the GBS dataset and sixteen disease rating datasets. Principal Component Analysis (PCA) was used an alternative to population structure analysis for studying population stratification from genotypic data. A significant association between disease phenotype and 528 SNPs was observed in six GWA analyses. Homology of sequences encompassing the significant SNPs was determined to predict gene identities and functions. Seventeen genes recurred in six GWA analyses, suggesting a strong association with virulence. Here, the putative genes/genomic regions associated with the significant SNPs are presented.

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Genome-wide association study (GWAS) for morphological and yield-related traits in an oil palm hybrid (Elaeis oleifera x Elaeis guineensis) population

10.21203/rs.2.13122/v3 ◽

2019 ◽

Author(s):

Jaime Osorio ◽

Gina Garzón ◽

Paola Delgadillo ◽

Silvio Bastidas ◽

Leidy Moreno ◽

...

Keyword(s):

Association Mapping ◽

Candidate Genes ◽

Oil Palm ◽

Plant Architecture ◽

Elaeis Guineensis ◽

Genotyping By Sequencing ◽

Genome Wide Association ◽

Elaeis Oleifera ◽

Genome Wide ◽

Genomic Regions

Abstract Background The genus Elaeis has two species of economic importance for the oil palm agroindustry: Elaeis oleifera (O), native to the Americas, and Elaeis guineensis (G), native to Africa. This work provides to our knowledge, the first association mapping study in an interspecific OxG oil palm population, which shows tolerance to pests and diseases, high oil quality, and acceptable fruit bunch production. Results Using genotyping-by-sequencing (GBS), we identified a total of 3,776 single nucleotide polymorphisms (SNPs) that were used to perform a genome-wide association analysis (GWAS) in 378 OxG hybrid population for 10 agronomic traits. Twelve genomic regions (SNPs) were located near candidate genes implicated in multiple functional categories, such as tissue growth, cellular trafficking, and physiological processes. Conclusions We provide new insights on genomic regions that mapped on candidate genes involved in plant architecture and yield. These potential candidate genes need to be confirmed for future targeted functional analyses. Associated markers to the traits of interest may be valuable resources for the development of marker-assisted selection in oil palm breeding. Keywords: Association mapping, Elaeis guineensis , Elaeis oleifera , genotyping-by-sequencing, plant architecture, yield.

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Genome-Wide Association Study of Root Mealiness and Other Texture-Associated Traits in Cassava

Frontiers in Plant Science ◽

10.3389/fpls.2021.770434 ◽

2021 ◽

Vol 12 ◽

Author(s):

Kelechi Uchendu ◽

Damian Ndubuisi Njoku ◽

Agre Paterne ◽

Ismail Yusuf Rabbi ◽

Daniel Dzidzienyo ◽

...

Keyword(s):

Candidate Genes ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Nucleotide Polymorphisms ◽

Phenotypic Data ◽

Genome Wide ◽

A Genome ◽

Breeding Programmes ◽

Vegetables And Fruits ◽

Genomic Regions

Cassava breeders have made significant progress in developing new genotypes with improved agronomic characteristics such as improved root yield and resistance against biotic and abiotic stresses. However, these new and improved cassava (Manihot esculenta Crantz) varieties in cultivation in Nigeria have undergone little or no improvement in their culinary qualities; hence, there is a paucity of genetic information regarding the texture of boiled cassava, particularly with respect to its mealiness, the principal sensory quality attribute of boiled cassava roots. The current study aimed at identifying genomic regions and polymorphisms associated with natural variation for root mealiness and other texture-related attributes of boiled cassava roots, which includes fibre, adhesiveness (ADH), taste, aroma, colour, and firmness. We performed a genome-wide association (GWAS) analysis using phenotypic data from a panel of 142 accessions obtained from the National Root Crops Research Institute (NRCRI), Umudike, Nigeria, and a set of 59,792 high-quality single nucleotide polymorphisms (SNPs) distributed across the cassava genome. Through genome-wide association mapping, we identified 80 SNPs that were significantly associated with root mealiness, fibre, adhesiveness, taste, aroma, colour and firmness on chromosomes 1, 4, 5, 6, 10, 13, 17 and 18. We also identified relevant candidate genes that are co-located with peak SNPs linked to these traits in M. esculenta. A survey of the cassava reference genome v6.1 positioned the SNPs on chromosome 13 in the vicinity of Manes.13G026900, a gene recognized as being responsible for cell adhesion and for the mealiness or crispness of vegetables and fruits, and also known to play an important role in cooked potato texture. This study provides the first insights into understanding the underlying genetic basis of boiled cassava root texture. After validation, the markers and candidate genes identified in this novel work could provide important genomic resources for use in marker-assisted selection (MAS) and genomic selection (GS) to accelerate genetic improvement of root mealiness and other culinary qualities in cassava breeding programmes in West Africa, especially in Nigeria, where the consumption of boiled and pounded cassava is low.

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MULTI-TRAIT MODELS FOR GENOMIC REGIONS ASSOCIATED WITH MAL DE RÍO CUARTO AND BACTERIAL DISEASE IN MAIZE

Journal of Basic and Applied Genetics ◽

10.35407/bag.2021.32.01.03 ◽

2021 ◽

Vol 32 (Issue 1) ◽

pp. 25-33

Author(s):

M. Ruiz ◽

E.A. Rossi ◽

N.C. Bonamico ◽

M.G. Balzarini

Keyword(s):

Association Study ◽

Genome Wide Association Study ◽

Mixed Linear Model ◽

Snp Markers ◽

Genome Wide Association ◽

Bacterial Disease ◽

Maize Germplasm ◽

Genome Wide ◽

A Genome ◽

Genomic Regions

Maize (Zea Mays L.) production has been greatly benefited from the improvement of inbred lines in regard to the resistance to diseases. However, the absence of resistant genotypes to bacteriosis is remarkable. The aim of the study was to identify genomic regions for resistance to Mal de Río Cuarto (MRC) and to bacterial disease (BD) in a diverse maize germplasm evaluated in the Argentinian region where MRC virus is endemic. A maize diverse population was assessed for both diseases during the 2019-2020 crop season. Incidence and severity of MRC and BD were estimated for each line and a genome wide association study (GWAS) was conducted with 78,376 SNP markers. A multi-trait mixed linear model was used for simultaneous evaluation of resistance to MRC and BD in the scored lines. The germplasm showed high genetic variability for both MRC and BD resistance. No significant genetic correlation was observed between the response to both diseases. Promising genomic regions for resistance to MRC and BD were identified and will be confirmed in further trials. Key words: maize disease; genome wide association study; SNP; multi-trait model

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