Genetic Structure and Eco-Geographical Differentiation of Wild Sheep Fescue (Festuca ovina L.) in Xinjiang, Northwest China

Glaciation and mountain orogeny have generated new ecologic opportunities for plants, favoring an increase in the speciation rate. Moreover, they also act as corridors or barriers for plant lineages and populations. High genetic diversity ensures that species are able to survive and adapt. Gene flow is one of the most important determinants of the genetic diversity and structure of out-crossed species, and it is easily affected by biotic and abiotic factors. The aim of this study was to characterize the genetic diversity and structure of an alpine species, Festuca ovina L., in Xingjiang, China. A total of 100 individuals from 10 populations were analyzed using six amplified fragment length polymorphism (AFLP) primer pairs. A total of 583 clear bands were generated, of which 392 were polymorphic; thus, the percentage of polymorphic bands (PPB) was 67.24%. The total and average genetic diversities were 0.2722 and 0.2006 (0.1686-0.2225), respectively. The unweighted group method with arithmetic mean (UPGMA) tree, principal coordinates analysis (PCoA) and STRUCTURE analyses revealed that these populations or individuals could be clustered into two groups. The analysis of molecular variance analysis (AMOVA) suggested that most of the genetic variance existed within a population, and the genetic differentiation (Fst) among populations was 20.71%. The Shannon differentiation coefficient (G’st) among populations was 0.2350. Limited gene flow (Nm = 0.9571) was detected across all sampling sites. The Fst and Nm presented at different levels under the genetic barriers due to fragmentation. The population genetic diversity was significant relative to environmental factors such as temperature, altitude and precipitation.

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Genetic Structure and Eco-Geographical Differentiation of Lancea tibetica in the Qinghai-Tibetan Plateau

Genes ◽

10.3390/genes10020097 ◽

2019 ◽

Vol 10 (2) ◽

pp. 97 ◽

Cited By ~ 2

Author(s):

Xiaofeng Chi ◽

Faqi Zhang ◽

Qingbo Gao ◽

Rui Xing ◽

Shilong Chen

Keyword(s):

Genetic Diversity ◽

Cluster Analysis ◽

Gene Flow ◽

Tibetan Plateau ◽

Environmental Changes ◽

Restricted Gene Flow ◽

Principal Coordinates Analysis ◽

Principal Coordinates ◽

Genetic Diversity And Structure ◽

Tanggula Mountains

The uplift of the Qinghai-Tibetan Plateau (QTP) had a profound impact on the plant speciation rate and genetic diversity. High genetic diversity ensures that species can survive and adapt in the face of geographical and environmental changes. The Tanggula Mountains, located in the central of the QTP, have unique geographical significance. The aim of this study was to investigate the effect of the Tanggula Mountains as a geographical barrier on plant genetic diversity and structure by using Lancea tibetica. A total of 456 individuals from 31 populations were analyzed using eight pairs of microsatellite makers. The total number of alleles was 55 and the number per locus ranged from 3 to 11 with an average of 6.875. The polymorphism information content (PIC) values ranged from 0.2693 to 0.7761 with an average of 0.4378 indicating that the eight microsatellite makers were efficient for distinguishing genotypes. Furthermore, the observed heterozygosity (Ho), the expected heterozygosity (He), and the Shannon information index (I) were 0.5277, 0.4949, and 0.9394, respectively, which indicated a high level of genetic diversity. We detected high genetic differentiation among all sampling sites and restricted gene flow among populations. Bayesian-based cluster analysis (STRUCTURE), principal coordinates analysis (PCoA), and Neighbor-Joining (NJ) cluster analysis based on microsatellite markers grouped the populations into two clusters: the southern branch and the northern branch. The analysis also detected genetic barriers and restricted gene flow between the two groups separated by the Tanggula Mountains. This study indicates that the geographical isolation of the Tanggula Mountains restricted the genetic connection and the distinct niches on the two sides of the mountains increased the intraspecific divergence of the plants.

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Genetic diversity and structure in the northern populations of European hazelnut (Corylus avellana L.)

Genome ◽

10.1139/gen-2018-0193 ◽

2019 ◽

Vol 62 (8) ◽

pp. 537-548

Author(s):

Pirjo Tanhuanpää ◽

Maarit Heinonen ◽

Lidija Bitz ◽

Veli-Matti Rokka

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Plant Conservation ◽

Corylus Avellana ◽

Ice Age ◽

Genetic Structuring ◽

Principal Coordinates Analysis ◽

Principal Coordinates ◽

Genetic Diversity And Structure ◽

Corylus Avellana L

European hazelnut (Corylus avellana L.) is a strictly cross-pollinated diploid tree species, which has its northernmost populations in Fennoscandia, and it was one of the first species to recolonize northern Europe after the last ice age. Hazelnut produces edible nuts in Finland but nowadays they are underutilized as food, and currently no breeding programmes exist. In the present study, 300 hazelnut specimens were collected from 20 different locations (= populations) in Finland, and they were genetically analyzed using nine simple sequence repeat (SSR) markers. Most of the genetic diversity existed within populations (83%). According to different genetic analyses (STRUCTURE, principal coordinates analysis, and clustering), a general lack of structure was observed, suggesting extensive gene flow among hazelnuts between 17 investigated populations. However, genetic structuring was clearly observed in three populations: Hakavuori, Mustiala, and Pähkinämäki, which might have become isolated due to geographical barriers that kept them separate, diminishing gene flow from other populations. Studying the diversity of European hazelnut is of great interest for understanding population genetics of a species distributed in its marginal areas in the north, and the results are also valuable for further uses in plant conservation, selection, and possible future breeding actions in Finland.

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Molecular characterization of sesame germplasms of West Bengal, India using RAPD markers

Acta Biologica Szegediensis ◽

10.14232/abs.2019.1.15-24 ◽

2019 ◽

Vol 63 (1) ◽

pp. 15-24

Author(s):

Soumen Saha ◽

Tarak Nath Dhar ◽

Parthadeb Ghosh ◽

Tulsi Dey

Keyword(s):

Genetic Diversity ◽

Rapd Markers ◽

West Bengal ◽

Genetic Relationships ◽

Random Amplified Polymorphic Dna ◽

Group Method ◽

Similarity Coefficients ◽

Principal Coordinates Analysis ◽

High Genetic Diversity ◽

Principal Coordinates

The aim of this research was to assess the genetic diversity of sesame (Sesamum indicum L.) and also to reveal the genetic relationships using the Random Amplified Polymorphic DNA (RAPD) markers. Fifteen sesame germplasms were collected from seven districts or four zones of West Bengal, India. A high genetic diversity was revealed by ten RAPD primers within and among the fifteen germplasms. The value of Jaccard’s similarity coefficients among and within the fifteen germplasms ranged from 0.287 to 0.725 which indicated high degree of genetic variability. Cluster analysis using Unweighted Pair Group Method with Arithmetic Mean (UPGMA) grouped all the germplasms into three main clusters. Analysis of various genetic diversity indices strongly indicated high level of genetic diversity among the populations of four different regions. UPGMA analysis of four populations resulted into two groups and the results of Principal Coordinates Analysis (PCoA) depicted a clear distinction among the germplasms.

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Revelation of genetic diversity and structure of wild Elymus excelsus (Poaceae: Triticeae) collection from western China by SSR markers

PeerJ ◽

10.7717/peerj.8038 ◽

2019 ◽

Vol 7 ◽

pp. e8038

Author(s):

Yanli Xiong ◽

Wenhui Liu ◽

Yi Xiong ◽

Qingqing Yu ◽

Xiao Ma ◽

...

Keyword(s):

Genetic Diversity ◽

Ssr Markers ◽

Western China ◽

Tibet Plateau ◽

Group Method ◽

Breeding Strategies ◽

Population Genetic Differentiation ◽

Principal Coordinates ◽

Geographical Regions ◽

Genetic Diversity And Structure

Hosting unique and important plant germplasms, the Qinghai-Tibet Plateau (QTP), as the third pole of the world, and Xinjiang, located in the centre of the Eurasian continent, are major distribution areas of perennial Triticeae grasses, especially the widespread Elymus species. Elymus excelsus Turcz. ex Griseb, a perennial forage grass with strong tolerance to environmental stresses, such as drought, cold and soil impoverishment, can be appropriately used for grassland establishment due to its high seed production. To provide basic information for collection, breeding strategies and utilization of E. excelsus germplasm, microsatellite markers (SSR) were employed in the present study to determine the genetic variation and population structure of 25 wild accessions of E. excelsus from Xinjiang (XJC) and the QTP, including Sichuan (SCC) and Gansu (GSC) of western China. Based on the 159 polymorphic bands amplified by 35 primer pairs developed from three related species, the average values of the polymorphic information content (PIC), marker index (MI), resolving power (Rp), Nei’s genetic diversity (H) and Shannon’s diversity index (I) of each pair of primers were 0.289, 1.348, 1.897, 0.301 and 0.459, respectively, validating that these SSR markers can also be used for the evaluation of genetic diversity of E. excelsus germplasms, and demonstrating the superior versatility of EST-SSR vs. G-SSR. We found a relatively moderate differentiation (Fst = 0.151) among the XJC, SCC and GSC geo-groups, and it is worth noting that, the intra-group genetic diversity of the SCC group (He = 0.197) was greater than that of the GSC (He = 0.176) and XJC (He = 0.148) groups. Both the Unweighted Pair Group Method with Arithmetic (UPGMA) clustering and principal coordinates analysis (PCoA) divided the 25 accessions into three groups, whereas the Bayesian STRUCTURE analysis suggested that E. excelsus accessions fell into four main clusters. Besides, this study suggested that geographical distance and environmental variables (annual mean precipitation and average precipitation in growing seasons), especially for QTP accessions, should be combined to explain the population genetic differentiation among the divergent geographical regions. These data provided comprehensive information about these valuable E. excelsus germplasm resources for the protection and collection of germplasms and for breeding strategies in areas of Xinjiang and QTP in western China.

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Microsatellite Characterization of Malaysian Mahseer (Tor spp.) for Improvement of Broodstock Management and Utilization

Animals ◽

10.3390/ani11092633 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2633

Author(s):

Poh Chiang Chew ◽

Annie Christianus ◽

Jaapar M. Zudaidy ◽

Md Yasin Ina-Salwany ◽

Chou Min Chong ◽

...

Keyword(s):

Genetic Variation ◽

Gene Flow ◽

Genetic Differentiation ◽

Genetic Relatedness ◽

Genetic Distances ◽

Group Method ◽

Genetic Management ◽

Principal Coordinates Analysis ◽

Principal Coordinates ◽

Geographical Regions

In this study, a mixture of Tor tambra and T. tambroides with unknown genetic background were collected from 11 localities in Malaysia for broodstock development and sperm cryo-banking. This study aims to assess the microsatellite (simple sequence repeat, SSR) variation, genetic diversity, genetic differentiation, level of gene flow, population structure, genetic relatedness and their demographic aspects among these Tor populations, in addition to establishing their SSR profile by employing 22 SSR markers via fragment analysis. Total genomic DNA was extracted from 181 samples (91 cryopreserved milt samples and 90 scale samples of live broodfish). Results showed the Tor spp. collection retained their genetic variation but exhibited excessive homozygosity among individuals within population. Moderate genetic differentiation was shown among the populations, with highly significant (p < 0.001) fixation indices (FST, FIS and FIT). A low gene flow over all loci (Nm 1.548) indicates little genetic variation transfer between populations. The genetic structures of all the populations were successfully resolved into four main clusters by an unweighted pair group method with arithmetic mean (UPGMA) dendrogram generated based on Nei’s genetic distances. The population structures based on principal coordinates analysis (PCoA) and the Bayesian model also suggested four distinct clusters following geographical regions and eight closely related populations. This study provided a useful baseline reference for better genetic management and utilization of the Tor spp. stocks in their breeding and conservation programmes.

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Genetic diversity in four cabbage populations based on random amplified polymorphic DNA markers

The Journal of Agricultural Science ◽

10.1017/s002185960500554x ◽

2005 ◽

Vol 143 (5) ◽

pp. 377-384 ◽

Cited By ~ 4

Author(s):

O. KOUTITA ◽

K. TERTIVANIDIS ◽

T. V. KOUTSOS ◽

M. KOUTSIKA-SOTIRIOU ◽

G. N. SKARACIS

Keyword(s):

Genetic Diversity ◽

Dna Markers ◽

Random Amplified Polymorphic Dna ◽

Population Diversity ◽

Group Method ◽

Jaccard Coefficient ◽

Gene Frequencies ◽

Principal Coordinates Analysis ◽

Arithmetic Average ◽

Principal Coordinates

Genetic diversity in four local Greek cabbage open-pollinated populations was investigated using RAPD (Random Amplified Polymorphic DNA) DNA markers in 18 individual plants from each population. A total of 24 random primers detected 90 polymorphic bands in the four populations studied, with an average of 3·75 bands/primer. The mean between-population differentiation was close to 40%, leaving 60% for within-population diversity. The individual plants were grouped, based on the Jaccard coefficient, by clustering (Unweighted Pair Group Method and Arithmetic Average – UPGMA) and an ordination (Principal Coordinates Analysis – PCO) methods, resulting in 7 and 6 groups, respectively. In general, there was a notable similarity in the grouping of the individuals with these two methods. In addition, Nei's standard genetic distance between populations, as calculated on the basis of within-population gene frequencies, was employed to group the populations by the UPGMA method. Clustering results were in good agreement with previously reported results based on morphological descriptors applied to the same populations. It was concluded that RAPD markers could be exploited as alternative or supplementary tools to already established methods for the evaluation and classification of cabbage genetic resources.

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Genetic diversity among Mycobacterium tuberculosis isolates from Mexican patients

Canadian Journal of Microbiology ◽

10.1139/w08-051 ◽

2008 ◽

Vol 54 (8) ◽

pp. 610-618

Author(s):

G. Vázquez-Marrufo ◽

D. Marín-Hernández ◽

M. G. Zavala-Páramo ◽

G. Vázquez-Narvaez ◽

C. Álvarez-Aguilar ◽

...

Keyword(s):

Genetic Diversity ◽

Mycobacterium Tuberculosis ◽

Gene Diversity ◽

Group Method ◽

Tuberculosis Complex ◽

Principal Coordinates Analysis ◽

Strain Distribution Pattern ◽

Pair Group ◽

Principal Coordinates ◽

Unweighted Pair Group Method

Forty-six isolates of the Mycobacterium tuberculosis complex were typified by PCR of the IS6110 region and by Mycobacterium bovis specific primers JB21/JB22. Isolate MVG01 was typified as M. bovis, being the first record of a case of human tuberculosis caused by this species in Mexico. RAPD–PCR was used to describe the genetic diversity of the remaining 45 M. tuberculosis complex isolates. The corrected genotypic diversity value calculated for the analyzed population was 0.96, the estimated mean gene diversity was 0.235, and the corrected Shannon–Weiner index was 2.15. All allele–loci combinations generated showed significant linkage disequilibria. The distribution of genetic variation was analyzed both by the unweighted pair group method with arithmetic averages clustering and by principal coordinates analysis. Unweighted pair group method with arithmetic averages clustering resulted in a tree with four main clusters and one unclustered strain (MVG20), the principal coordinates analysis strain distribution pattern being consistent with this grouping. The obtained results suggest that the studied isolates belong to a clonal population having significant genetic diversity. Our genetic diversity results are comparable with those reported for other populations of M. tuberculosis, although only three RAPD primers were used.

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DNA barcode reference library construction and genetic diversity and structure analysis of Amomum villosum Lour. (Zingiberaceae) populations in Guangdong Province

PeerJ ◽

10.7717/peerj.12325 ◽

2021 ◽

Vol 9 ◽

pp. e12325

Author(s):

Lu Gong ◽

Danchun Zhang ◽

Xiaoxia Ding ◽

Juan Huang ◽

Wan Guan ◽

...

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Genetic Differentiation ◽

Dna Barcode ◽

Group Method ◽

Germplasm Resources ◽

Dna Barcodes ◽

Reference Library ◽

Genetic Diversity And Structure ◽

Amomum Villosum

Background Amomum villosum Lour. is the plant that produces the famous traditional Chinese medicine Amomi Fructus. Frequent habitat destruction seriously threatens A. villosum germplasm resources. Genetic diversity is very important to the optimization of germplasm resources and population protection, but the range of inherited traits within A. villosum is unclear. In this study, we analyzed the genetic diversity and genetic structures of A. villosum populations in Guangdong and constructed a local reference DNA barcode library as a resource for conservation efforts. Methods DNA barcoding and Inter-Simple Sequence Repeat (ISSR) markers were used to investigate the population genetics of A. villosum. Five universal DNA barcodes were amplified and used in the construction of a DNA barcode reference library. Parameters including percentage of polymorphic sites (PPB), number of alleles (Na), effective number of alleles (Ne), Nei’s gene diversity index (H), and Shannon’s polymorphism information index (I) were calculated for the assessment of genetic diversity. Genetic structure was revealed by measuring Nei’s gene differentiation coefficient (Gst), total population genetic diversity (Ht), intra-group genetic diversity (Hs), and gene flow (Nm). Analysis of molecular variance (AMOVA), Mantel tests, unweighted pair-group method with arithmetic mean (UPGMA) dendrogram, and principal co-ordinates (PCoA) analysis were used to elucidate the genetic differentiation and relationship among populations. Results A total of 531 sequences were obtained from the five DNA barcodes with no variable sites from any of the barcode sequences. A total of 66 ISSR bands were generated from A. villosum populations using the selected six ISSR primers; 56 bands, 84.85% for all the seven A. villosum populations were polymorphic. The A. villosum populations showed high genetic diversity (H = 0.3281, I = 0.4895), whereas the gene flow was weak (Nm = 0.6143). Gst (0.4487) and AMOVA analysis indicated that there is obvious genetic differentiation amongA. villosum populations and more genetic variations existed within each population. The genetic relationship of each population was relatively close as the genetic distances were between 0.0844 and 0.3347.

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Genetic Diversity Among Some Walnut (Juglans regia L.) Genotypes by SSR Markers

Sustainability ◽

10.3390/su13126830 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6830

Author(s):

Murat Guney ◽

Salih Kafkas ◽

Hakan Keles ◽

Mozhgan Zarifikhosroshahi ◽

Muhammet Ali Gundesli ◽

...

Keyword(s):

Genetic Diversity ◽

Plant Genetic Resources ◽

Juglans Regia ◽

Genetic Distances ◽

Mean Value ◽

Central Anatolia ◽

Group Method ◽

Arithmetic Average ◽

Pair Group ◽

Principal Coordinates

The food needs for increasing population, climatic changes, urbanization and industrialization, along with the destruction of forests, are the main challenges of modern life. Therefore, it is very important to evaluate plant genetic resources in order to cope with these problems. Therefore, in this study, a set of ninety-one walnut (Juglans regia L.) accessions from Central Anatolia region, composed of seventy-four accessions and eight commercial cultivars from Turkey, and nine international reference cultivars, was analyzed using 45 SSR (Simple Sequence Repeats) markers to reveal the genetic diversity. SSR analysis identified 390 alleles for 91 accessions. The number of alleles per locus ranged from 3 to 19 alleles with a mean value of 9 alleles per locus. Genetic dissimilarity coefficients ranged from 0.03 to 0.68. The highest number of alleles was obtained from CUJRA212 locus (Na = 19). The values of polymorphism information content (PIC) ranged from 0.42 (JRHR222528) to 0.86 (CUJRA212) with a mean PIC value of 0.68. Genetic distances were estimated according to the UPGMA (Unweighted Pair Group Method with Arithmetic Average), Principal Coordinates (PCoA), and the Structure-based clustering. The UPGMA and Structure clustering of the accessions depicted five major clusters supporting the PCoA results. The dendrogram revealed the similarities and dissimilarities among the accessions by identifying five major clusters. Based on this study, SSR analyses indicate that Yozgat province has an important genetic diversity pool and rich genetic variance of walnuts.

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Genetic structure and diversity of the mustard hill coral Porites astreoides along the Florida Keys reef tract

Marine Biodiversity ◽

10.1007/s12526-021-01196-7 ◽

2021 ◽

Vol 51 (4) ◽

Author(s):

Dominique N. Gallery ◽

Michelle L. Green ◽

Ilsa B. Kuffner ◽

Elizabeth A. Lenz ◽

Lauren T. Toth

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Genetic Relatedness ◽

Florida Keys ◽

Genetic Population ◽

High Genetic Diversity ◽

Western Atlantic ◽

Porites Astreoides ◽

Single Well ◽

Reef Tract

AbstractIncreases in local and global stressors have led to major declines in coral populations throughout the western Atlantic. While abundances of other species have declined, however, the relative abundance of the mustard hill coral, Porites astreoides, has increased. Porites astreoides is relatively resilient to some stressors, and because of its mixed reproductive strategies, its populations often recover quickly following disturbances. The ability for P. astreoides to continue as a potential “winner” in western Atlantic reefs relies on maintaining sufficient genetic variation within populations to support acclimatization and adaptation to current and future environmental change. Without high genetic diversity and gene flow within the population, it would have limited capacity for adaptation and the species’ competitive advantages could be short-lived. In this study, we determined the genetic relatedness of 37 P. astreoides colonies at four shallow reefs along the offshore Florida Keys Reef Tract (FKRT), a region particularly hard-hit by recent disturbances. Using previously designed microsatellite markers, we determined the genetic diversity and connectivity of individuals among and between sites. Our results suggest that the FKRT likely contains a single, well-mixed genetic population of P. astreoides, with high levels of gene flow and evidence for larval migration throughout the region. This suggests that regional populations of P. astreoides likely have a higher chance of maintaining resilience than many other western Atlantic species as they face current and future disturbances.

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