Identification of a Diverse Core Set Panel of Rice From the East Coast Region of India Using SNP Markers

In India, rice (Oryza sativa L.) is cultivated under a variety of climatic conditions. Due to the fragility of the coastal ecosystem, rice farming in these areas has lagged behind. Salinity coupled with floods has added to this trend. Hence, to prevent genetic erosion, conserving and characterizing the coastal rice, is the need of the hour. This work accessed the genetic variation and population structure among 2,242 rice accessions originating from India’s east coast comprising Andhra Pradesh, Orissa, and Tamil Nadu, using 36 SNP markers, and have generated a core set (247 accessions) as well as a mini-core set (30 accessions) of rice germplasm. All the 36 SNP loci were biallelic and 72 alleles found with average two alleles per locus. The genetic relatedness of the total collection was inferred using the un-rooted neighbor-joining tree, which grouped all the genotypes (2,242) into three major clusters. Two groups were obtained with a core set and three groups obtained with a mini core set. The mean PIC value of total collection was 0.24, and those of the core collection and mini core collection were 0.27 and 0.32, respectively. The mean heterozygosity and gene diversity of the overall collection were 0.07 and 0.29, respectively, and the core set and mini core set revealed 0.12 and 0.34, 0.20 and 0.40 values, respectively, representing 99% of distinctiveness in the core and mini core sets. Population structure analysis showed maximum population at K = 4 for total collection and core collection. Accessions were distributed according to their population structure confirmed by PCoA and AMOVA analysis. The identified small and diverse core set panel will be useful in allele mining for biotic and abiotic traits and managing the genetic diversity of the coastal rice collection. Validation of the 36-plex SNP assay was done by comparing the genetic diversity parameters across two different rice core collections, i.e., east coast and northeast rice collection. The same set of SNP markers was found very effective in deciphering diversity at different genetic parameters in both the collections; hence, these marker sets can be utilized for core development and diversity analysis studies.

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Genotyping-By-Sequencing Reveals Population Structure and Genetic Diversity of a Buffelgrass (Cenchrus ciliaris L.) Collection

Diversity ◽

10.3390/d12030088 ◽

2020 ◽

Vol 12 (3) ◽

pp. 88

Author(s):

Alemayehu Teressa Negawo ◽

Yilikal Assefa ◽

Jean Hanson ◽

Asebe Abdena ◽

Meki S. Muktar ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Core Collection ◽

Reference Genome ◽

Genotyping By Sequencing ◽

Snp Markers ◽

Soil Conditions ◽

Cenchrus Ciliaris ◽

Population Structure Analysis ◽

Wide Range

Buffelgrass (Cenchrus ciliaris L.) is an important forage grass widely grown across the world with many good characteristics including high biomass yield, drought tolerance, and adaptability to a wide range of soil conditions and agro-ecologies. Two hundred and five buffelgrass accessions from diverse origins, conserved as part of the in-trust collection in the ILRI genebank, were analyzed by genotyping-by-sequencing using the DArTseq platform. The genotyping generated 234,581 single nucleotide polymorphism (SNP) markers, with polymorphic information content (PIC) values ranging from 0.005 to 0.5, and the short sequences of the markers were aligned with foxtail millet (Setaria italica) as a reference genome to generate genomic map positions of the markers. One thousand informative SNP markers, representing a broad coverage of the reference genome and with an average PIC value of 0.35, were selected for population structure and diversity analyses. The population structure analysis suggested two main groups, while the hierarchical clustering showed up to eight clusters in the collection. A representative core collection containing 20% of the accessions in the collection, with germplasm from 10 African countries and Oman, was developed. In general, the study revealed the presence of considerable genetic diversity and richness in the collection and a core collection that could be used for further analysis for specific traits of interest.

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Population Structure and Genetic Diversity in Korean Cowpea Germplasm Based on SNP Markers

Plants ◽

10.3390/plants9091190 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1190 ◽

Cited By ~ 1

Author(s):

Eunju Seo ◽

Kipoong Kim ◽

Tae-Hwan Jun ◽

Jinsil Choi ◽

Seong-Hoon Kim ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Principal Component ◽

Snp Markers ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Useful Knowledge ◽

Population Structure Analysis ◽

Group 3 ◽

Genetic Diversity Study

Cowpea is one of the most essential legume crops providing inexpensive dietary protein and nutrients. The aim of this study was to understand the genetic diversity and population structure of global and Korean cowpea germplasms. A total of 384 cowpea accessions from 21 countries were genotyped with the Cowpea iSelect Consortium Array containing 51,128 single-nucleotide polymorphisms (SNPs). After SNP filtering, a genetic diversity study was carried out using 35,116 SNPs within 376 cowpea accessions, including 229 Korean accessions. Based on structure and principal component analysis, a total of 376 global accessions were divided into four major populations. Accessions in group 1 were from Asia and Europe, those in groups 2 and 4 were from Korea, and those in group 3 were from West Africa. In addition, 229 Korean accessions were divided into three major populations (Q1, Jeonra province; Q2, Gangwon province; Q3, a mixture of provinces). Additionally, the neighbor-joining tree indicated similar results. Further genetic diversity analysis within the global and Korean population groups indicated low heterozygosity, a low polymorphism information content, and a high inbreeding coefficient in the Korean cowpea accessions. The population structure analysis will provide useful knowledge to support the genetic potential of the cowpea breeding program, especially in Korea.

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Genetic Diversity and Variability in Endangered Pantesco and Two Other Sicilian Donkey Breeds Assessed by Microsatellite Markers

The Scientific World JOURNAL ◽

10.1100/2012/648427 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Salvatore Bordonaro ◽

Anna Maria Guastella ◽

Andrea Criscione ◽

Antonio Zuccaro ◽

Donata Marletta

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Genetic Variability ◽

Genetic Information ◽

Gene Diversity ◽

Genetic Distances ◽

Conservation Strategies ◽

Population Structure Analysis ◽

The Mean ◽

Differentiation Index

The genetic variability of Pantesco and other two Sicilian autochthonous donkey breeds (Ragusano and Grigio Siciliano) was assessed using a set of 14 microsatellites. The main goals were to describe the current differentiation among the breeds and to provide genetic information useful to safeguard the Pantesco breed as well as to manage Ragusano and Grigio Siciliano. In the whole sample, that included 108 donkeys representative of the three populations, a total of 85 alleles were detected. The mean number of alleles was lower in Pantesco (3.7), than in Grigio Siciliano and Ragusano (4.4 and 5.9, resp.). The three breeds showed a quite low level of gene diversity (He) ranging from 0.471 in Pantesco to 0.589 in Grigio. The overall genetic differentiation index (Fst) was quite high; more than 10% of the diversity was found among breeds. Reynolds’ () genetic distances, correspondence, and population structure analysis reproduced the same picture, revealing that, (a) Pantesco breed is the most differentiated in the context of the Sicilian indigenous breeds, (b) within Ragusano breed, two well-defined subgroups were observed. This information is worth of further investigation in order to provide suitable data for conservation strategies.

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Genetic diversity and population structure analysis of bambara groundnut (Vigna subterrenea L) landraces using DArT SNP markers

PLoS ONE ◽

10.1371/journal.pone.0253600 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0253600

Author(s):

Charles U. Uba ◽

Happiness O. Oselebe ◽

Abush A. Tesfaye ◽

Wosene G. Abtew

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

West Africa ◽

East Africa ◽

Unknown Origin ◽

Snp Markers ◽

Bambara Groundnut ◽

Conservation Strategy ◽

Population Structure Analysis ◽

Geographical Regions

Understanding the genetic structure and diversity of crops facilitates progress in plant breeding. A collection of 270 bambara groundnut (Vigna subterrenea L) landraces sourced from different geographical regions (Nigeria/Cameroon, West, Central, Southern and East Africa) and unknown origin (sourced from United Kingdom) was used to assess genetic diversity, relationship and population structure using DArT SNP markers. The major allele frequency ranged from 0.57 for unknown origin to 0.91 for West Africa region. The total gene diversity (0.482) and Shannon diversity index (0.787) was higher in West African accessions. The genetic distance between pairs of regions varied from 0.002 to 0.028 with higher similarity between Nigeria/Cameroon-West Africa accessions and East-Southern Africa accessions. The analysis of molecular variance (AMOVA) revealed 89% of genetic variation within population, 8% among regions and 3% among population. The genetic relatedness among the collections was evaluated using neighbor joining tree analysis, which grouped all the geographic regions into three major clusters. Three major subgroups of bambara groundnut were identified using the ADMIXTURE model program and confirmed by discriminant analysis of principal components (DAPC). These subgroups were West Africa, Nigeria/Cameroon and unknown origin that gave rise to sub-population one, and Central Africa was sub-population two, while Southern and East Africa were sub-population three. In general, the results of all the different analytical methods used in this study confirmed the existence of high level of diversity among the germplasm used in this study that might be utilized for future genetic improvement of bambara groundnut. The finding also provides new insight on the population structure of African bambara groundnut germplasm which will help in conservation strategy and management of the crop.

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Population Structure Analysis Revealed Water or Ancient Hub-induced Genetic Diversity of Cultivated-type Tea Plants in Guizhou Plateau

10.21203/rs.3.rs-964671/v1 ◽

2021 ◽

Author(s):

Zhifei Zhao ◽

Qinfei Song ◽

Dingchen Bai ◽

Suzhen Niu ◽

Yingqin He ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Structure Analysis ◽

Core Collection ◽

Genotyping By Sequencing ◽

Tea Plant ◽

Transmission Model ◽

Population Structure Analysis ◽

Tea Plants ◽

Guizhou Plateau

Abstract Background Tea plants originated from the southwest of China. Guizhou is one of the origin center of tea plants, which is rich in tea plant germplasm resources. However, the distribution characteristics and transmission model of tea plant were still unclear. Results We collected 253 cultivated-type tea plant accessions from Guizhou plateau and analyzed the genetic diversity, PCA, phylogenetic, population structure, LD, and development of core collection using the genotyping-by-sequencing (GBS) approach. A total of 112,072 high-quality SNPs were identified, which was further used to analyze the genetic diversity and population structure. In this study, we found that the genetic diversity in cultivated-type tea accessions of PR Basin were significantly higher than that in cultivated-type tea accessions of YR Basin. Moreover, four groups, including three pure groups (CG-1, CG-2 and CG-3) and one admixture group (CG-4), were identified based on population structure analysis, which was verified by PAC and phylogenetic analysis. Our results showed that the highest GD and Fst values were found in CG-2 vs CG-3, followed by CG-1 vs CG-2 and CG-1 vs CG-3. The lowest GD and Fst values were detected in CG-4 vs CG-1, CG-4 vs CG-2, and CG-4 vs CG-3. Conclusions This study provided the evidence to confirm the contribution of PR and YR Basins and ancient hub road section to the transmission of cultivated-type tea accessions in Guizhou plateau. The genetic diversity, population structure and core collection revealed by our study will benefit further genetic studies, germplasm protection, and breeding.

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Genetic Diversity and Population Structure of a Rhodes Grass (Chloris gayana) Collection

Genes ◽

10.3390/genes12081233 ◽

2021 ◽

Vol 12 (8) ◽

pp. 1233

Author(s):

Alemayehu Teressa Negawo ◽

Meki S. Muktar ◽

Yilikal Assefa ◽

Jean Hanson ◽

Alieu M. Sartie ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Polymorphic Information Content ◽

Snp Markers ◽

Correction Coefficient ◽

Rhodes Grass ◽

Representative Subset ◽

Population Structure Analysis ◽

Chloris Gayana ◽

Molecular Information

Rhodes grass (Chloris gayana Kunth) is one of the most important forage grasses used throughout the tropical and subtropical regions of the world. Enhancing the conservation and use of genetic resources requires the development of knowledge and understanding about the existing global diversity of the species. In this study, 104 Rhodes grass accessions, held in trust in the ILRI forage genebank, were characterized using DArTSeq markers to evaluate the genetic diversity and population structure, and to develop representative subsets, of the collection. The genotyping produced 193,988 SNP and 142,522 SilicoDArT markers with an average polymorphic information content of 0.18 and 0.26, respectively. Hierarchical clustering using selected informative markers showed the presence of two and three main clusters using SNP and SilicoDArT markers, respectively, with a cophenetic correction coefficient of 82%. Bayesian population structure analysis also showed the presence of two main subpopulations using both marker types indicating the existence of significant genetic variation in the collection. A representative subset, containing 21 accessions from diverse origins, was developed using the SNP markers. In general, the results revealed substantial genetic diversity in the Rhodes grass collection, and the generated molecular information, together with the developed subset, should help enhance the management, use and improvement of Rhodes grass germplasm in the future.

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Whole Genome Diversity, Population Structure, and Linkage Disequilibrium Analysis of Chickpea (Cicer arietinum L.) Genotypes Using Genome-Wide DArTseq-Based SNP Markers

Genes ◽

10.3390/genes10090676 ◽

2019 ◽

Vol 10 (9) ◽

pp. 676 ◽

Cited By ~ 3

Author(s):

Farahani ◽

Maleki ◽

Mehrabi ◽

Kanouni ◽

Scheben ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Linkage Disequilibrium ◽

Large Scale ◽

Principal Component ◽

Snp Markers ◽

Genome Diversity ◽

High Genetic Diversity ◽

Breeding Programs ◽

Population Structure Analysis

Characterization of genetic diversity, population structure, and linkage disequilibrium is a prerequisite for proper management of breeding programs and conservation of genetic resources. In this study, 186 chickpea genotypes, including advanced “Kabuli” breeding lines and Iranian landrace “Desi” chickpea genotypes, were genotyped using DArTseq-Based single nucleotide polymorphism (SNP) markers. Out of 3339 SNPs, 1152 markers with known chromosomal position were selected for genome diversity analysis. The number of mapped SNP markers varied from 52 (LG8) to 378 (LG4), with an average of 144 SNPs per linkage group. The chromosome size that was covered by SNPs varied from 16,236.36 kbp (LG8) to 67,923.99 kbp (LG5), while LG4 showed a higher number of SNPs, with an average of 6.56 SNPs per Mbp. Polymorphism information content (PIC) value of SNP markers ranged from 0.05 to 0.50, with an average of 0.32, while the markers on LG4, LG6, and LG8 showed higher mean PIC value than average. Unweighted neighbor joining cluster analysis and Bayesian-based model population structure grouped chickpea genotypes into four distinct clusters. Principal component analysis (PCoA) and discriminant analysis of principal component (DAPC) results were consistent with that of the cluster and population structure analysis. Linkage disequilibrium (LD) was extensive and LD decay in chickpea germplasm was relatively low. A few markers showed r2 ≥ 0.8, while 2961 pairs of markers showed complete LD (r2 = 1), and a huge LD block was observed on LG4. High genetic diversity and low kinship value between pairs of genotypes suggest the presence of a high genetic diversity among the studied chickpea genotypes. This study also demonstrates the efficiency of DArTseq-based SNP genotyping for large-scale genome analysis in chickpea. The genotypic markers provided in this study are useful for various association mapping studies when combined with phenotypic data of different traits, such as seed yield, abiotic, and biotic stresses, and therefore can be efficiently used in breeding programs to improve chickpea.

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Comparing the efficiency of sampling strategies to establish a representative in the phenotypic-based genetic diversity core collection of orchardgrass (Dactylis glomerata L.)

Czech Journal of Genetics and Plant Breeding ◽

10.17221/9/2012-cjgpb ◽

2013 ◽

Vol 49 (No. 1) ◽

pp. 36-47 ◽

Cited By ~ 4

Author(s):

M. Studnicki ◽

W. Mądry ◽

J. Schmidt

Keyword(s):

Genetic Diversity ◽

Core Collection ◽

Dactylis Glomerata ◽

Sampling Strategy ◽

Sampling Strategies ◽

Core Collections ◽

The Core ◽

Entire Collection ◽

The Mean ◽

Dactylis Glomerata L

Establishing a core collection that represents the genetic diversity of the entire collection with a minimum loss of its original diversity and minimal redundancies is an important problem for gene bank curators and crop breeders. In this paper, we assess the representativeness of the original genetic diversity in core collections consisting of one-tenth of the entire collection obtained according to 23 sampling strategies. The study was performed using the Polish orchardgrass Dactylis glomerata L. germplasm collection as a model. The representativeness of the core collections was validated by the difference of means (MD%) and difference of mean squared Euclidean distance (d‒D%) for the studied traits in the core subsets and the entire collection. In this way, we compared the efficiency of a simple random and 22 (20 cluster-based and 2 direct cluster-based) stratified sampling strategies. Each cluster-based stratified sampling strategy is a combination of 2 clusterings, 5 allocations and 2 methods of sampling in a group. We used the accession genotypic predicted values for 8 quantitative traits tested in field trials. A sampling strategy is considered more effective for establishing core collections if the means of the traits in a core are maintained at the same level as the means in the entire collection (i.e., the mean of MD% in the simulated samples is close to zero) and, simultaneously, when the overall variation in a core collection is greater than in the entire collection (i.e., the mean of d‒D% in the simulated samples is greater than that obtained for the simple random sampling strategy). Both cluster analyses (unweighted pair group method with arithmetic mean UPGMA and Ward) were similarly useful in constructing those sampling strategies capable of establishing representative core collections. Among the allocation methods that are relatively most useful for constructing efficient samplings were proportional and D2 (including variation). Within the Ward clusters, the random sampling was better than the cluster-based sampling, but not within the UPGMA clusters.

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Population Genetic Diversity and Structure of an Endangered Salicaceae Species in Northeast China: Chosenia arbutifolia (Pall.) A. Skv.

Forests ◽

10.3390/f12091282 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1282

Author(s):

Yu Wang ◽

Zhongyi Jiao ◽

Jiwei Zheng ◽

Jie Zhou ◽

Baosong Wang ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Management Strategies ◽

Natural Populations ◽

Snp Markers ◽

Fixation Index ◽

Landscape Genomics ◽

Population Structure Analysis ◽

Genetic Diversity And Structure ◽

Chosenia Arbutifolia

Chosenia arbutifolia (Pall.) A. Skv. is a unique and endangered species belonging to the Salicaceae family. It has great potential for ornamental and industrial use. However, human interference has led to a decrease in and fragmentation of its natural populations in the past two decades. To effectively evaluate, utilize, and conserve available resources, the genetic diversity and population structure of C. arbutifolia were analyzed in this study. A total of 142 individuals from ten provenances were sampled and sequenced. Moderate diversity was detected among these, with a mean expected heterozygosity and Shannon’s Wiener index of 0.3505 and 0.5258, respectively. The inbreeding coefficient was negative, indicating a significant excess of heterozygotes. The fixation index varied from 0.0068 to 0.3063, showing a varied genetic differentiation between populations. Analysis of molecular variance demonstrated that differentiation accounted for 82.23% of the total variation among individuals, while the remaining 17.77% variation was between populations. Furthermore, the results of population structure analysis indicated that the 142 individuals originated from three primitive groups. To provide genetic information and help design conservation and management strategies, landscape genomics analysis was performed by investigating loci associated with environmental variables. Eighteen SNP markers were associated with altitude and annual average temperature, of which five were ascribed with specific functions. In conclusion, the current study furthers the understanding of C. arbutifolia genetic architecture and provides insights for germplasm protection.

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Whole Genome Diversity, Population Structure and Linkage Disequilibrium Analysis of Chickpea (Cicer arietinum L.) Genotypes Using Genome-Wide DArTseq-Based SNP Markers

10.20944/preprints201904.0321.v1 ◽

2019 ◽

Author(s):

Somayeh Farahani ◽

Mojdeh Maleki ◽

Rahim Mehrabi ◽

Homayoun Kanouni ◽

Reza Talebi

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Linkage Disequilibrium ◽

Large Scale ◽

Principal Component ◽

Snp Markers ◽

Genome Diversity ◽

High Genetic Diversity ◽

Breeding Programs ◽

Population Structure Analysis

Characterization of genetic diversity, population structure and linkage disequilibrium is prerequisite for proper management of breeding programs and conservation of genetic resources. In this study, 186 chickpea genotypes including advanced “Kabuli” breeding lines and Iranian landrace “Desi” chickpea genotypes were genotyped using DArTseq-Based SNP markers. Out of 3339 SNPs, 1152 markers with known chromosomal position were selected for genome diversity analysis. The number of mapped SNP markers varied from 52 (LG8) to 378 (LG4), with an average of 144 SNPs per linkage group. The chromosome size that covered by SNPs varied from 16236.36 kbp (LG8) to 67923.99 kbp (LG5), while LG4 showed higher number of SNPs, with an average of 6.56 SNPs per Mbp. Polymorphism information content (PIC) value of SNP markers ranged from 0.05 to 0.50, with an average of 0.32, while the markers on LG4, LG6 and LG8 showed higher mean PIC value than average. Un-weighted Neighbor Joining cluster analysis and Bayesian-based model population structure grouped chickpea genotypes into four distinct clusters. Principal component analysis (PCoA) and Discriminant Analysis of Principal Component (DAPC) results were consistent with that of the cluster and population structure analysis. Linkage disequilibrium (LD) was extensive and LD decay in chickpea germplasm was relatively low. A few markers showed r2≥0.8, while 2961 pairs of markers showed complete LD (r2=1) and a huge LD block was observed on LG4. High genetic diversity and low kinship value between pairs of genotypes suggesting the presence of a high genetic diversity among studied chickpea genotypes. This study also demonstrated the efficiency of DArTseq-based SNP genotyping for large scale genome analysis in chickpea. The genotypic markers provided in this study are useful for various association mapping studies when combined with phenotypic data of different traits such as seed yield, abiotic and biotic stresses and therefore can be efficiently used in breeding programs to improve chickpea.

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