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

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 Analysis of Growth Curve Parameters in Chinese Simmental Beef Cattle

Animals ◽

10.3390/ani11010192 ◽

2021 ◽

Vol 11 (1) ◽

pp. 192

Author(s):

Xinghai Duan ◽

Bingxing An ◽

Lili Du ◽

Tianpeng Chang ◽

Mang Liang ◽

...

Keyword(s):

Beef Cattle ◽

Candidate Genes ◽

Growth Curve ◽

Growth And Development ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Coefficient Of Determination ◽

Nucleotide Polymorphisms ◽

Genome Wide ◽

A Genome

The objective of the present study was to perform a genome-wide association study (GWAS) for growth curve parameters using nonlinear models that fit original weight–age records. In this study, data from 808 Chinese Simmental beef cattle that were weighed at 0, 6, 12, and 18 months of age were used to fit the growth curve. The Gompertz model showed the highest coefficient of determination (R2 = 0.954). The parameters’ mature body weight (A), time-scale parameter (b), and maturity rate (K) were treated as phenotypes for single-trait GWAS and multi-trait GWAS. In total, 9, 49, and 7 significant SNPs associated with A, b, and K were identified by single-trait GWAS; 22 significant single nucleotide polymorphisms (SNPs) were identified by multi-trait GWAS. Among them, we observed several candidate genes, including PLIN3, KCNS3, TMCO1, PRKAG3, ANGPTL2, IGF-1, SHISA9, and STK3, which were previously reported to associate with growth and development. Further research for these candidate genes may be useful for exploring the full genetic architecture underlying growth and development traits in livestock.

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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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Genome-wide Association Study and Possible Candidate Genes for Root Color and Carotenoid Contents in Japanese Orange Carrot F2 Populations

10.21203/rs.3.rs-1014140/v1 ◽

2021 ◽

Author(s):

Taeko Shibaya ◽

Chika Kuroda ◽

Hisano Tsuruoka ◽

Chiharu Minami ◽

Akiko Obara ◽

...

Keyword(s):

Amino Acid ◽

Association Study ◽

Candidate Genes ◽

Genome Wide Association Study ◽

Carotenoid Biosynthesis ◽

Genome Wide Association ◽

Nucleotide Polymorphisms ◽

Visual Evaluation ◽

Genome Wide ◽

A Genome

Abstract Carrot is a major source of provitamin A in a human diet. Two of the most important traits for carrot breeding are carotenoid contents and root color. To examine genomic regions related to these traits and develop DNA markers for carrot breeding, we performed a genome-wide association study (GWAS) using genome-wide single-nucleotide polymorphisms (SNPs) in two F2 populations, both derived from crosses of orange root carrots bred by a Japanese seed company. The GWAS revealed 21 significant associations, and the physical position of some associations suggested two possible candidate genes. An Orange (Or) gene was a possible candidate for visual color evaluation and the α- and β-carotene contents. Sanger sequencing detected a new allele of Or with an SNP which caused a non-synonymous amino acid substitution. Genotypes of this SNP corresponded to the visual evaluation of root color in another breeding line. A chromoplast-specific lycopene β-cyclase (CYC-B) gene was a possible candidate for the β/α carotene ratio. On CYC-B, five amino acid substitutions were detected between parental plants of the F2 population. The detected associations and SNPs on the possible candidate genes will contribute to carrot breeding and the understanding of carotenoid biosynthesis and accumulation in orange carrots.

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Genome-Wide Association Analysis of Plant Height Using the Maize F1 Population

Plants ◽

10.3390/plants8100432 ◽

2019 ◽

Vol 8 (10) ◽

pp. 432 ◽

Cited By ~ 1

Author(s):

Zhang ◽

Wan ◽

He ◽

Lan ◽

Keyword(s):

Candidate Genes ◽

Plant Height ◽

Genetic Basis ◽

Genome Wide Association Study ◽

Plant Density ◽

Genome Wide Association ◽

Nucleotide Polymorphisms ◽

Higher Plant ◽

Genome Wide ◽

A Genome

Drastic changes in plant height (PH) are observed when maize adapt to a higher plant density. Most importantly, PH is an important factor affecting maize yield. Although the genetic basis of PH has been extensively studied using different populations during the past decades, genetic basis remains unclear in the F1 population, which was a widely used population in production. In this study, a genome-wide association study (GWAS) was conducted using an F1 population consisting of 300 maize hybrids with 17,652 single nucleotide polymorphisms (SNPs) makers to identify candidate genes for controlling PH. A total of nine significant SNPs makers and two candidate genes were identified for PH. The candidate genes, Zm00001d018617 and Zm00001d023659, were the genes most probable to be involved in the development of PH. Our results provide new insights into the genetic basis of PH in maize.

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Genome-Wide Association Study (GWAS) for Examining the Genomics Controlling Prickle Production in Red Raspberry (Rubus idaeus L.)

Agronomy ◽

10.3390/agronomy11010027 ◽

2020 ◽

Vol 11 (1) ◽

pp. 27

Author(s):

Archana Khadgi ◽

Courtney A. Weber

Keyword(s):

Association Study ◽

Genome Wide Association Study ◽

Genomic Region ◽

Rubus Idaeus ◽

Genome Wide Association ◽

Nucleotide Polymorphisms ◽

Red Raspberry ◽

Genome Wide ◽

A Genome ◽

Genotype By Sequencing

Red raspberry (Rubus idaeus L.) is an expanding high-value berry crop worldwide. The presence of prickles, outgrowths of epidermal tissues lacking vasculature, on the canes, petioles, and undersides of leaves complicates both field management and harvest. The utilization of cultivars with fewer prickles or prickle-free canes simplifies production. A previously generated population segregating for prickles utilizing the s locus between the prickle-free cultivar Joan J (ss) and the prickled cultivar Caroline (Ss) was analyzed to identify the genomic region associated with prickle development in red raspberry. Genotype by sequencing (GBS) was combined with a genome-wide association study (GWAS) using fixed and random model circulating probability unification (FarmCPU) to analyze 8474 single nucleotide polymorphisms (SNPs) and identify significant markers associated with the prickle-free trait. A total of four SNPs were identified on chromosome 4 that were associated with the phenotype and were located near or in annotated genes. This study demonstrates how association genetics can be used to decipher the genetic control of important horticultural traits in Rubus, and provides valuable information about the genomic region and potential genes underlying the prickle-free trait.

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Genome-Wide Association Study Reveals the Genetic Basis of Cold Tolerance in Rice at the Seedling Stage

Agriculture ◽

10.3390/agriculture11040318 ◽

2021 ◽

Vol 11 (4) ◽

pp. 318

Author(s):

Tae-Ho Ham ◽

Yebin Kwon ◽

Yoonjung Lee ◽

Jisu Choi ◽

Joohyun Lee

Keyword(s):

Association Study ◽

Candidate Genes ◽

Cold Tolerance ◽

Genome Wide Association Study ◽

Seedling Stage ◽

Genome Wide Association ◽

Matrix Analysis ◽

Rice Seedlings ◽

Genome Wide ◽

A Genome

We conducted a genome-wide association study (GWAS) of cold tolerance in a collection of 127 rice accessions, including 57 Korean landraces at the seedling stage. Cold tolerance of rice seedlings was evaluated in a growth chamber under controlled conditions and scored on a 0–9 scale, based on their low-temperature response and subsequent recovery. GWAS, together with principal component analysis (PCA) and kinship matrix analysis, revealed four quantitative trait loci (QTLs) on chromosomes 1, 4, and 5 that explained 16.5% to 18.5% of the variance in cold tolerance. The genomic region underlying the QTL on chromosome four overlapped with a previously reported QTL associated with cold tolerance in rice seedlings. Similarly, one of the QTLs identified on chromosome five overlapped with a previously reported QTL associated with seedling vigor. Subsequent bioinformatic and haplotype analyses revealed three candidate genes affecting cold tolerance within the linkage disequilibrium (LD) block of these QTLs: Os01g0357800, encoding a pentatricopeptide repeat (PPR) domain-containing protein; Os05g0171300, encoding a plastidial ADP-glucose transporter; and Os05g0400200, encoding a retrotransposon protein, Ty1-copia subclass. The detected QTLs and further evaluation of these candidate genes in the future will provide strategies for developing cold-tolerant rice in breeding programs.

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Evaluation of candidate genes in a genome-wide association study of childhood asthma in Mexicans

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2009.09.007 ◽

2010 ◽

Vol 125 (2) ◽

pp. 321-327.e13 ◽

Cited By ~ 60

Author(s):

Hao Wu ◽

Isabelle Romieu ◽

Min Shi ◽

Dana B. Hancock ◽

Huiling Li ◽

...

Keyword(s):

Association Study ◽

Candidate Genes ◽

Childhood Asthma ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Genome Wide ◽

A Genome

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Genome-wide association analysis of resistance to Pseudoperonospora cubensis in citron watermelon

Plant Disease ◽

10.1094/pdis-08-21-1611-re ◽

2021 ◽

Author(s):

Dennis Katuuramu ◽

Sandra Branham ◽

Amnon Levi ◽

Patrick Wechter

Keyword(s):

Candidate Genes ◽

Genome Wide Association Study ◽

Citrullus Lanatus ◽

Phenotypic Variability ◽

Germplasm Collection ◽

Snp Markers ◽

Genome Wide Association ◽

Pseudoperonospora Cubensis ◽

Genome Wide ◽

A Genome

Cultivated sweet watermelon (Citrullus lanatus) is an important vegetable crop for millions of people around the world. There are limited sources of resistance to economically important diseases within C. lanatus, whereas Citrullus amarus has a reservoir of traits that can be exploited to improve C. lanatus for resistance to biotic and abiotic stresses. Cucurbit downy mildew (CDM), caused by Pseudoperonospora cubensis, is an emerging threat to watermelon production. We screened 122 C. amarus accessions for resistance to CDM over two tests (environments). The accessions were genotyped by whole-genome resequencing to generate 2,126,759 single nucleotide polymorphic (SNP) markers. A genome-wide association study was deployed to uncover marker-trait associations and identify candidate genes underlying resistance to CDM. Our results indicate the presence of wide phenotypic variability (1.1 - 57.8%) for leaf area infection, representing a 50.7-fold variation for CDM resistance across the C. amarus germplasm collection. Broad-sense heritability estimate was 0.55, implying the presence of moderate genetic effects for resistance to CDM. The peak SNP markers associated with resistance to P. cubensis were located on chromosomes Ca03, Ca05, Ca07, and Ca11. The significant SNP markers accounted for up to 30% of the phenotypic variation and were associated with promising candidate genes encoding disease resistance proteins, leucine-rich repeat receptor-like protein kinase, and WRKY transcription factor. This information will be useful in understanding the genetic architecture of the P. cubensis-Citrullus spp. patho-system as well as development of resources for genomics-assisted breeding for resistance to CDM in watermelon.

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A Genome-Wide Association Study Reveals Candidate Genes Related to Salt Tolerance in Rice (Oryza sativa) at the Germination Stage

International Journal of Molecular Sciences ◽

10.3390/ijms19103145 ◽

2018 ◽

Vol 19 (10) ◽

pp. 3145 ◽

Cited By ~ 8

Author(s):

Jie Yu ◽

Weiguo Zhao ◽

Wei Tong ◽

Qiang He ◽

Min-Young Yoon ◽

...

Keyword(s):

Salt Tolerance ◽

Association Study ◽

Candidate Genes ◽

Genome Wide Association Study ◽

Rice Genome ◽

Genome Wide Association ◽

Phenotypic Correlation ◽

Genome Wide ◽

A Genome ◽

Germination Stage

Salt toxicity is the major factor limiting crop productivity in saline soils. In this paper, 295 accessions including a heuristic core set (137 accessions) and 158 bred varieties were re-sequenced and ~1.65 million SNPs/indels were used to perform a genome-wide association study (GWAS) of salt-tolerance-related phenotypes in rice during the germination stage. A total of 12 associated peaks distributed on seven chromosomes using a compressed mixed linear model were detected. Determined by linkage disequilibrium (LD) blocks analysis, we finally obtained a total of 79 candidate genes. By detecting the highly associated variations located inside the genic region that overlapped with the results of LD block analysis, we characterized 17 genes that may contribute to salt tolerance during the seed germination stage. At the same time, we conducted a haplotype analysis of the genes with functional variations together with phenotypic correlation and orthologous sequence analyses. Among these genes, OsMADS31, which is a MADS-box family transcription factor, had a down-regulated expression under the salt condition and it was predicted to be involved in the salt tolerance at the rice germination stage. Our study revealed some novel candidate genes and their substantial natural variations in the rice genome at the germination stage. The GWAS in rice at the germination stage would provide important resources for molecular breeding and functional analysis of the salt tolerance during rice germination.

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Haplotypes within tandemly duplicated candidate genes at BnaA9.MRP5 modulate phytate concentration in canola (Brassica napus L.)

10.22541/au.161165160.08519096/v1 ◽

2021 ◽

Author(s):

Haijiang Liu ◽

xiaojuan Li ◽

Qianwen Zhang ◽

pan yuan ◽

Lei Liu ◽

...

Keyword(s):

Candidate Genes ◽

Oilseed Rape ◽

Genome Wide Association Study ◽

Mineral Elements ◽

Nucleotide Polymorphisms ◽

Brassica Napus L ◽

Single Nucleotide ◽

Genome Wide ◽

A Genome ◽

Phytate Content

Phytate is the storage form of phosphorus in angiosperm seeds and plays vitally important roles during seed development. However, in crop plants phytate decreases bioavailability of seed-sourced mineral elements for humans, livestock and poultry, and contributes to phosphate-related water pollution. However, there is little knowledge about this trait in oilseed rape B. napus (oilseed rape). Here, a panel of 505 diverse B. napus accessions was screened in a genome-wide association study (GWAS) using 3.28 x 106 single nucleotide polymorphisms (SNPs). This identified 119 SNPs significantly associated with phytate concentration (PA_Conc) and phytate content (PA_Cont) and six candidate genes were identified. Of these, BnaA9.MRP5 represented the candidate gene for the significant SNP chrA09_5198034 (27kb) for both PA_Cont and PA_Conc. Transcription of BnaA9.MRP5 in a low -phytate variety (LPA20) was significantly elevated compared with a high -phytate variety (HPA972). Association and haplotype analysis indicated that inbred lines carrying specific SNP haplotypes within BnaA9.MRP5 were associated with high- and low-phytate phenotypes. No significant differences in seed germination and seed yield were detected between low and high phytate cultivars examined. Candidate genes, favorable haplotypes and the low phytate varieties identified in this study will be useful for low-phytate breeding of B. napus.

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