Genetic diversity and structure of landrace accessions, elite lineages and cultivars of common bean estimated with SSR and SNP markers

The common bean (Phaseolus vulgaris L.) is one of the main legumes worldwide and represents a valuable source of nutrients. Independent domestication events in the Americas led to the formation of two cultivated genepools, namely Mesoamerican and Andean, to which European material has been brought back. In this study, Italian common bean landraces were analyzed for their genetic diversity and structure, using single nucleotide polymorphism (SNP) markers derived from genotyping-by-sequencing (GBS) technology. After filtering, 11,866 SNPs were obtained and 798 markers, pruned for linkage disequilibrium, were used for structure analysis. The most probable number of subpopulations (K) was two, consistent with the presence of the two genepools, identified through the phaseolin diagnostic marker. Some landraces were admixed, suggesting probable hybridization events between Mesoamerican and Andean material. When increasing the number of possible Ks, the Andean germplasm appeared to be structured in two or three subgroups. The subdivision within the Andean material was also observed in a principal coordinate analysis (PCoA) plot and a dendrogram based on genetic distances. The Mesoamerican landraces showed a higher level of genetic diversity compared to the Andean landraces. Calculation of the fixation index (FST) at individual SNPs between the Mesoamerican and Andean genepools and within the Andean genepool evidenced clusters of highly divergent loci in specific chromosomal regions. This work may help to preserve landraces of the common bean from genetic erosion, and could represent a starting point for the identification of interesting traits that determine plant adaptation.

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Population structure and genetic diversity in a commercial maize breeding program assessed with SSR and SNP markers

Theoretical and Applied Genetics ◽

10.1007/s00122-009-1256-2 ◽

2010 ◽

Vol 120 (7) ◽

pp. 1289-1299 ◽

Cited By ~ 156

Author(s):

Delphine Van Inghelandt ◽

Albrecht E. Melchinger ◽

Claude Lebreton ◽

Benjamin Stich

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Snp Markers ◽

Breeding Program ◽

Maize Breeding ◽

Ssr And Snp Markers

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Population structure and genetic diversity analyses of common bean germplasm collections of East and Southern Africa using morphological traits and high-density SNP markers

PLoS ONE ◽

10.1371/journal.pone.0243238 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0243238

Author(s):

Wilson Nkhata ◽

Hussein Shimelis ◽

Rob Melis ◽

Rowland Chirwa ◽

Tenyson Mzengeza ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Genetic Variation ◽

Common Bean ◽

Southern Africa ◽

Crop Improvement ◽

Phenotypic Expression ◽

Snp Markers ◽

High Yield ◽

Gene Pools

Knowledge of genetic diversity in plant germplasm and the relationship between genetic factors and phenotypic expression is vital for crop improvement. This study's objectives were to understand the extent of genetic diversity and population structure in 60 common bean genotypes from East and Southern Africa. The common bean genotypes exhibited significant (p<0.05) levels of variability for traits such as days to flowering (DTF), days to maturity (DTM), number of pods per plant (NPP), number of seeds per pod (NSP), and grain yield per hectare in kilograms (GYD). About 47.82 per cent of the variation among the genotypes was explained by seven principal components (PC) associated with the following agronomic traits: NPP, NFF (nodes to first flower), DTF, GH (growth habit) and GYD. The SNP markers revealed mean gene diversity and polymorphic information content values of 0.38 and 0.25, respectively, which suggested the presence of considerable genetic variation among the assessed genotypes. Analysis of molecular variance showed that 51% of the genetic variation were between the gene pools, while 49% of the variation were within the gene pools. The genotypes were delineated into two distinct groups through the population structure, cluster and phylogenetic analyses. Genetically divergent genotypes such as DRK57, MW3915, NUA59, and VTTT924/4-4 with high yield and agronomic potential were identified, which may be useful for common bean improvement.

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Genetic Diversity and Population Structure of Kerala Rice Landraces Using Genotyping-By-Sequencing

10.21203/rs.3.rs-516783/v1 ◽

2021 ◽

Author(s):

Maya Peringottillam ◽

Smitha Kunhiraman Vasumathy ◽

Hari Krishna Kumar ◽

Manickavelu Alagu

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Genotyping By Sequencing ◽

Snp Markers ◽

Genetic Purity ◽

Next Generation Sequencing Technology ◽

Distance Analysis ◽

Rice Landraces ◽

Genetic Diversity And Structure ◽

Rice Landrace

Abstract Researchers stand at the vanguard of advancement and application of next-generation sequencing technology for creating opportunities to guide more realistic and applicable strategies for the sustainable management of genetically diverse rice resources. This study is a pioneering effort where GBS-SNP markers were employed to assess the tremendous genetic diversity and structure of rice landrace collections from northern Kerala. Kerala holds an immense diversity of rice landraces that encountered selection pressures of environmental heterogeneity, biotic and abiotic stresses, however competent rather provide good yields, whereby drawing the attention of the rice breeding sector. The population structure and diversity analyses separated the accessions into three distinct subpopulations with a huge amount of genetic variation within subpopulations. Nei’s genetic distance analysis confirmed the existence of strong genetic differentiation among rice landrace populations. The values of FST and Nm established the farmers’ effort to preserve the genetic purity of rice landraces despite the extensive seed exchange programs across the states of India. Moreover, this low level of gene flow among subpopulations could provide the opportunity for well-adapted combinations of genes to be established by natural selection. The clustering pattern based on SNP markers furnished sufficient knowledge in identifying rice genotypes that eliminates the likelihood of duplication among indigenous cultivars. Similar clustering patterns of genotypes revealed shared genetic characters among them. Collectively these analyses can be used to completely understand the population of rice landraces in Kerala while contributing insights toward the evolution and selective pressures underlying these unique landraces.

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Genetic Diversity in Jatropha curcas L. Assessed with SSR and SNP Markers

Diversity ◽

10.3390/d6030551 ◽

2014 ◽

Vol 6 (3) ◽

pp. 551-566 ◽

Cited By ~ 25

Author(s):

Juan Montes ◽

Frank Technow ◽

Matthias Martin ◽

Klaus Becker

Keyword(s):

Genetic Diversity ◽

Jatropha Curcas ◽

Snp Markers ◽

Jatropha Curcas L ◽

Ssr And Snp Markers

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Genetic Diversity, Linkage Disequilibrium and Population Structure of Bulgarian Bread Wheat Assessed by Genome-Wide Distributed SNP Markers: From Old Germplasm to Semi-Dwarf Cultivars

Plants ◽

10.3390/plants10061116 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1116

Author(s):

Vladimir Aleksandrov ◽

Tania Kartseva ◽

Ahmad M. Alqudah ◽

Konstantina Kocheva ◽

Krasimira Tasheva ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Linkage Disequilibrium ◽

Bread Wheat ◽

Clustering Algorithm ◽

Agronomic Traits ◽

Gene Diversity ◽

Geographic Region ◽

Snp Markers ◽

Genetic Diversity And Structure

Genetic diversity and population structure are key resources for breeding purposes and genetic studies of important agronomic traits in crops. In this study, we described SNP-based genetic diversity, linkage disequilibrium and population structure in a panel of 179 bread wheat advanced cultivars and old accessions from Bulgaria, using an optimized wheat 25K Infinium iSelect array. Out of 19,019 polymorphic SNPs, 17,968 had а known chromosome position on the A (41%), B (42%) and D (11%) genome, and 6% were not assigned to any chromosome. Homoeologous group 4, in particular chromosome 4D, was the least polymorphic. In the total population, the Nei’s gene diversity was within the range 0.1-0.5, and the polymorphism information content ranged from 0.1 to 0.4. Significant differences between the old and modern collections were revealed with respect to the linkage disequilibrium (LD): the average values for LD (r2), the percentage of the locus pairs in LD and the LD decay were 0.64, 16% and 3.3 for the old germplasm, and 0.43, 30% and 4.1 for the modern releases, respectively. Structure and k-means clustering algorithm divided the panel into three groups. The old accessions formed a distinct subpopulation. The cluster analysis further distinguished the modern releases according to the geographic region and genealogy. Gene exchange was evidenced mainly between the subpopulations of contemporary cultivars. The achieved understanding of the genetic diversity and structure of the Bulgarian wheat population and distinctiveness of the old germplasm could be of interest for breeders developing cultivars with improved characteristics. The obtained knowledge about SNP informativeness and the LD estimation are worthwhile for selecting markers and for considering the composition of a population in association mapping studies of traits of interest.

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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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Genetic Diversity and Population Structure of Sorghum [Sorghum Bicolor (L.) Moench] Accessions as Revealed by Single Nucleotide Polymorphism Markers

Frontiers in Plant Science ◽

10.3389/fpls.2021.799482 ◽

2022 ◽

Vol 12 ◽

Author(s):

Muluken Enyew ◽

Tileye Feyissa ◽

Anders S. Carlsson ◽

Kassahun Tesfaye ◽

Cecilia Hammenhag ◽

...

Keyword(s):

Genetic Diversity ◽

Single Nucleotide Polymorphism ◽

Sorghum Bicolor ◽

Conservation Status ◽

Snp Markers ◽

Ex Situ ◽

Eastern Region ◽

Nucleotide Polymorphism ◽

Single Nucleotide ◽

Landrace Accessions

Ethiopia is the center of origin for sorghum [Sorghum bicolor (L.) Moench], where the distinct agro-ecological zones significantly contributed to the genetic diversity of the crops. A large number of sorghum landrace accessions have been conserved ex situ. Molecular characterization of this diverse germplasm can contribute to its efficient conservation and utilization in the breeding programs. This study aimed to investigate the genetic diversity of Ethiopian sorghum using gene-based single nucleotide polymorphism (SNP) markers. In total, 359 individuals representing 24 landrace accessions were genotyped using 3,001 SNP markers. The SNP markers had moderately high polymorphism information content (PIC = 0.24) and gene diversity (H = 0.29), on average. This study revealed 48 SNP loci that were significantly deviated from Hardy–Weinberg equilibrium with excess heterozygosity and 13 loci presumed to be under selection (P < 0.01). The analysis of molecular variance (AMOVA) determined that 35.5% of the total variation occurred within and 64.5% among the accessions. Similarly, significant differentiations were observed among geographic regions and peduncle shape-based groups. In the latter case, accessions with bent peduncles had higher genetic variation than those with erect peduncles. More alleles that are private were found in the eastern region than in the other regions of the country, suggesting a good in situ conservation status in the east. Cluster, principal coordinates (PCoA), and STRUCTURE analyses revealed distinct accession clusters. Hence, crossbreeding genotypes from different clusters and evaluating their progenies for desirable traits is advantageous. The exceptionally high heterozygosity observed in accession SB4 and SB21 from the western geographic region is an intriguing finding of this study, which merits further investigation.

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