Ancestry, population structure, and conservation genetics of Arctic grayling (Thymallus arcticus) in the upper Missouri River, USA

2009 ◽  
Vol 66 (10) ◽  
pp. 1758-1774 ◽  
Author(s):  
Douglas P. Peterson ◽  
William R. Ardren

We genotyped Arctic grayling ( Thymallus arcticus ) at 10 microsatellite loci in 18 samples (n = 726) from Montana, Wyoming, and Saskatchewan to determine genetic relationships among native, captive, and naturalized populations in the upper Missouri River basin, to assess patterns in genetic diversity, and to infer recent demographic histories. Substantial genetic subdivision was observed among sample populations (global FST = 0.10). Canadian populations have been isolated from Missouri River populations long enough for mutation to cause genetic differences between regions (mean pairwise FST = 0.18, RST = 0.54). Within the Missouri River basin, most naturalized lacustrine populations traced their ancestry to Red Rock lakes. Two populations in headwater lakes within the Big Hole River watershed appear to be native. We found neither evidence for introgression of Canadian-origin grayling nor any effect of hatchery stocking in native populations. The native fluvial Big Hole River group was genetically distinct and most diverse (HE = 0.89), whereas native Madison River and Red Rock lakes populations exhibited lower genetic diversity (HE = 0.74 and 0.80, respectively) and evidence of recent bottlenecks. The existing Big Hole and Red Rock populations are at low abundance but do not appear to be at immediate risk of inbreeding depression (Ne = 207.7–228.2).

2021 ◽  
Author(s):  
Varun Hiremath ◽  
Kanwar Pal Singh ◽  
Neelu Jain ◽  
Kishan Swaroop ◽  
Pradeep Kumar Jain ◽  
...  

Abstract Genetic diversity and structure analysis using molecular markers is necessary for efficient utilization and sustainable management of gladiolus germplasm. Genetic analysis of gladiolus germplasm using SSR markers is largely missing due to scarce genomic information. In the present investigation, we report 66.66% cross transferability of Gladiolus palustris SSRs whereas 48% of Iris EST-SSRs were cross transferable across the gladiolus genotypes used in the study. A total of 17 highly polymorphic SSRs revealed a total 58 polymorphic loci ranging from two to six in each locus with an average of 3.41 alleles per marker. PIC values ranged from 0.11 to 0.71 with an average value of 0.48. Four SSRs were selectively neutral based on Ewens-Watterson test. Analysis of genetic structure of 84 gladiolus genotypes divided whole germplasm into two subpopulations. 35 genotypes were assigned to subpopulation 1 whereas 37 to subpopulation 2 and rest of the genotypes recorded as admixture. Analysis of molecular variance indicated maximum variance (53.59%) among individuals within subpopulations whereas 36.55% of variation observed among individuals within total population. Least variation (9.86%) was noticed between two subpopulations. Moderate (FST = 0.10) genetic differentiation of two subpopulations was observed. Grouping pattern of population structure was consistent with UPGMA dendrogram based on simple matching dissimilarity coefficient (ranged from 01.6 to 0.89) and PCoA. Genetic relationships assessed among the genotypes of respective clusters assist the breeders in selecting desirable parents for crossing. SSR markers from present study can be utilized for cultivar identification, conservation and sustainable utilization of gladiolus genotypes for crop improvement.


2020 ◽  
Author(s):  
Brenda G. Díaz ◽  
Maria I. Zucchi ◽  
Alessandro. Alves-Pereira ◽  
Caléo P. de Almeida ◽  
Aline C. L. Moraes ◽  
...  

AbstractAcrocomia (Arecaceae) is a genus widely distributed in tropical and subtropical America that has been achieving economic interest due to the great potential of oil production of some of its species. In particular A. aculeata, due to its vocation to supply oil with the same productive capacity as the oil palm even in areas with water deficit. Although eight species are recognized in the genus, the taxonomic classification based on morphology and geographic distribution is still controversial. Knowledge about the genetic diversity and population structure of the species is limited, which has limited the understanding of the genetic relationships and the orientation of management, conservation, and genetic improvement activities of species of the genus. In the present study, we analyzed the genomic diversity and population structure of seven species of Acrocomia including 117 samples of A. aculeata covering a wide geographical area of occurrence, using single nucleotide Polymorphism (SNP) markers originated from Genotyping By Sequencing (GBS). The genetic structure of the Acrocomia species were partially congruent with the current taxonomic classification based on morphological characters, recovering the separation of the species A. aculeata, A. totai, A. crispa and A. intumescens as distinct taxonomic groups. However, the species A. media was attributed to the cluster of A. aculeata while A. hassleri and A. glauscescens were grouped together with A. totai. The species that showed the highest and lowest genetic diversity were A. totai and A. media, respectively. When analyzed separately, the species A. aculeata showed a strong genetic structure, forming two genetic groups, the first represented mainly by genotypes from Brazil and the second by accessions from Central and North American countries. Greater genetic diversity was found in Brazil when compared to the other countries. Our results on the genetic diversity of the genus are unprecedented, as is also establishes new insights on the genomic relationships between Acrocomia species. It is also the first study to provide a more global view of the genomic diversity of A. aculeata. We also highlight the applicability of genomic data as a reference for future studies on genetic diversity, taxonomy, evolution and phylogeny of the Acrocomia genus, as well as to support strategies for the conservation, exploration and breeding of Acrocomia species and in particular A. aculeata.


BMC Genetics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Cun Chen ◽  
Yanguang Chu ◽  
Changjun Ding ◽  
Xiaohua Su ◽  
Qinjun Huang

Abstract Background Black cottonwood (Populus deltoides) is one of the keystone forest tree species, and has become the main breeding parents in poplar hybrid breeding. However, the genetic diversity and population structure of the introduced resources are not fully understood. Results In the present study, five loci containing null alleles were excluded and 15 pairs of SSR (simple sequence repeat) primers were used to analyze the genetic diversity and population structure of 384 individuals from six provenances (Missouri, Iowa, Washington, Louisiana, and Tennessee (USA), and Quebec in Canada) of P. deltoides. Ultimately, 108 alleles (Na) were detected; the expected heterozygosity (He) per locus ranged from 0.070 to 0.905, and the average polymorphic information content (PIC) was 0.535. The provenance ‘Was’ had a relatively low genetic diversity, while ‘Que’, ‘Lou’, and ‘Ten’ provenances had high genetic diversity, with Shannon’s information index (I) above 1.0. The mean coefficient of genetic differentiation (Fst) and gene flow (Nm) were 0.129 and 1.931, respectively. Analysis of molecular variance (AMOVA) showed that 84.88% of the genetic variation originated from individuals. Based on principal coordinate analysis (PCoA) and STRUCTURE cluster analysis, individuals distributed in the Mississippi River Basin were roughly classified as one group, while those distributed in the St. Lawrence River Basin and Columbia River Basin were classified as another group. The cluster analysis based on the population level showed that provenance ‘Iow’ had a small gene flow and high degree of genetic differentiation compared with the other provenances, and was classified into one group. There was a significant relationship between genetic distance and geographical distance. Conclusions P. deltoides resources have high genetic diversity and there is a moderate level of genetic differentiation among provenances. Geographical isolation and natural conditions may be the main factors causing genetic differences among individuals. Individuals reflecting population genetic information can be selected to build a core germplasm bank. Meanwhile, the results could provide theoretical support for the scientific management and efficient utilization of P. deltoides genetic resources, and promote the development of molecular marker-assisted breeding of poplar.


2009 ◽  
Vol 54 (No. 10) ◽  
pp. 468-474 ◽  
Author(s):  
S. Kusza ◽  
E. Gyarmathy ◽  
J. Dubravska ◽  
I. Nagy ◽  
A. Jávor ◽  
...  

In this study genetic diversity, population structure and genetic relationships of Tsigai populations in Slovakia were investigated using microsatellite markers. Altogether 195 animals from 12 populations were genotyped for 16 microsatellites. 212 alleles were detected on the loci. The number of identified alleles per locus ranged from 11 to 35. In the majority of the populations heterozygosity deficiency and potential risks of inbreeding could be determined. High values of <I>F</I><sub>ST</sub> (0.133) across all the loci revealed a substantial degree of population differentiation. The estimation of genetic distance value showed that the Slovak Vojin population was the most different from the other populations. The 12 examined populations were able to group into 4 clusters. With this result our aim is to help the Slovak sheep breeders to establish their own mating system, to avoid genetic loss and to prevent diversity of Tsigai breed in Slovakia.


2009 ◽  
Vol 75 (10) ◽  
pp. 3187-3195 ◽  
Author(s):  
E. Gentekaki ◽  
D. H. Lynn

ABSTRACT Studies that assess intraspecific genetic variation in ciliates are few and quite recent. Consequently, knowledge of the subject and understanding of the processes that underlie it are limited. We sought to assess the degree of intraspecific genetic variation in Carchesium polypinum (Ciliophora: Peritrichia), a cosmopolitan, freshwater ciliate. We isolated colonies of C. polypinum from locations in the Grand River basin in Southwestern Ontario, Canada. We then used the nuclear markers—ITS1, ITS2, and the hypervariable regions of the large subunit rRNA—and an 819-bp fragment of the mitochondrial cytochrome c oxidase I gene (cox-1) to investigate the intraspecific genetic variation of C. polypinum and the degree of resolution of the above-mentioned markers at the population level. We also sought to determine whether the organism demonstrated any population structure that mapped onto the geography of the region. Our study shows that there is a high degree of genetic diversity at the isolate level, revealed by the mitochondrial markers but not the nuclear markers. Furthermore, our results indicate that C. polypinum is likely not a single morphospecies as previously thought.


2013 ◽  
Vol 5 (2) ◽  
pp. 139-143
Author(s):  
Vellaichamy RAMANADEVI ◽  
Muthusamy THANGARAJ ◽  
Anbazhagan SURESHKUMAR ◽  
Jayachandran SUBBURAJ

Due to the environmental changes and habitat destruction the mudskipper fish population is decreasing in recent years. To predict the fish population structure, frequent manual survey and molecular methods are widely used. Molecular markers such as RAPD, microsatellite, allozyme, D-loop haplotype are frequently adopted to assess the population structure of an organism. In this study ten- arbitrary primers were screened to estimate the genetic relationships and diversity of two mudskipper species (Boleophthalmus boddarti and B. dussumieri) in Vellar estuary, Tamilnadu, India. By this RAPD marker study, the genetic diversity (H) in B. boddarti was more (0.0116 ± 0.0066) than in B. dussumieri (0.0056 ± 0.0024) in Vellar estuary (India). The genetic distance between B. boddarti and B. dussumieri was 1.7943. By observing the species specific bands and the phylogenetic analysis it is revealed that these two species clearly deviated into separate clusters emphasizing the distinct species status.


2004 ◽  
Vol 70 (12) ◽  
pp. 7210-7219 ◽  
Author(s):  
Blanca de las Rivas ◽  
Ángela Marcobal ◽  
Rosario Muñoz

ABSTRACT Oenococcus oeni is the organism of choice for promoting malolactic fermentation in wine. The population biology of O. oeni is poorly understood and remains unclear. For a better understanding of the mode of genetic variation within this species, we investigated by using multilocus sequence typing (MLST) with the gyrB, pgm, ddl, recP, and mleA genes the genetic diversity and genetic relationships among 18 O. oeni strains isolated in various years from wines of the United States, France, Germany, Spain, and Italy. These strains have also been characterized by ribotyping and restriction fragment length polymorphism (RFLP) analysis of the PCR-amplified 16S-23S rRNA gene intergenic spacer region (ISR). Ribotyping grouped the strains into two groups; however, the RFLP analysis of the ISRs showed no differences in the strains analyzed. In contrast, MLST in oenococci had a good discriminatory ability, and we have found a higher genetic diversity than indicated by ribotyping analysis. All sequence types were represented by a single strain, and all the strains could be distinguished from each other because they had unique combinations of alleles. Strains assumed to be identical showed the same sequence type. Phylogenetic analyses indicated a panmictic population structure in O. oeni. Sequences were analyzed for evidence of recombination by split decomposition analysis and analysis of clustered polymorphisms. All results indicated that recombination plays a major role in creating the genetic heterogeneity of O. oeni. A low standardized index of association value indicated that the O. oeni genes analyzed are close to linkage equilibrium. This study constitutes the first step in the development of an MLST method for O. oeni and the first example of the application of MLST to a nonpathogenic food production bacteria.


2021 ◽  
Author(s):  
Chao Du ◽  
Bai Mo ◽  
Wujiao Li ◽  
Wencong Liu ◽  
Zongxiu Hu ◽  
...  

Abstract Rhesus monkeyss (Macaca mulatta) are extensively used in the field of medical and psychological research as valuable experimental animals. 15 polymorphic chromosome-specific microsatellite markers were used to analyze the genetic diversity and population structure in two captive individuals. A total of 155 alleles were identified, with the number of alleles per locus ranging from 7 to 15, giving an average number of 10.3 alleles per locus. The mean number of effective alleles (Ne), observed heterozygosity (Ho), expected heterozygosity (He), and the polymorphism information content (PIC) were 5.602, 0.7297, 0.8016, and 0.7716, respectively. The populations HS and XJ shared partial common alleles, however, the remaining in XJ were not detected. Structure analysis indicated that two populations belong to three genetic lineages. AMOVA showed that the genetic variance was 91% among individuals, while it was 9% among populations, respectively. The bottleneck effect analysis revealed that the two captive populations were in accordance with mutation-drift equilibrium. In the comparison of the genetic parameters and structure between the HS and XJ, we speculated that the genetic diversity was higher, which may be attributed to the exchange of germplasm resources and the input of new individuals from wild populations.


Author(s):  
Shuying Yin ◽  
Yanrong Wang ◽  
Zhibiao Nan

This study aimed to understand the genetic diversity and population structure of alfalfa germplasm from the United States. In this study, the population structure and genetic diversity of six alfalfa cultivars of United States origin were investigated by microsatellite analysis with 40 individuals per cultivar. A total of 312 discernible alleles were amplified from the whole genome with an average of 31.2 alleles per locus. The average values of polymorphic information content and Shannon’s information index were 0.928 and 0.133, respectively, showing high levels of genetic diversity. Two populations were identified by STRUCTURE software with principal coordinate analysis and neighbour-joining clustering. Analysis of molecular variance analysis (AMOVA) revealed that the majority of genetic variation was within cultivars (96.42%) rather than between cultivars (3.58%). In conclusion, analyses of genetic diversity and population structure may be useful for the genetic analysis and utilization of genetic variation in alfalfa breeding.


2012 ◽  
Vol 92 (4) ◽  
pp. 417-423 ◽  
Author(s):  
Jinjun Li ◽  
Qingyuan Yuan ◽  
Junda Shen ◽  
Zhengrong Tao ◽  
Guoqing Li ◽  
...  

Li, J., Yuan, Q., Shen, J., Tao, Z., Li, G., Tian, Y., Wang, D., Chen, L. and Lu, L. 2012. Evaluation of the genetic diversity and population structure of five indigenous and one introduced Chinese goose breeds using microsatellite markers. Can. J. Anim. Sci. 92: 417–423. The aim of this study was to determine the genetic diversity and evolutionary relationships among five indigenous Chinese goose breeds and one introduced goose breed using 29 microsatellite markers. A total of 334 distinct alleles were observed across the six breeds, and 45 of the 334 alleles (13.5%) were unique to only one breed. The indigenous geese showed higher diversity in terms of the observed number of alleles per locus (4.48–5.90) and observed heterozygosity (0.46–0.53) compared with the introduced breed (3.97 and 0.29, respectively). The pairwise genetic differentiation (FST) between the six goose breeds ranged from 0.04 between Panshi Grey goose (PS) and Yongkang Grey goose to 0.47 between PS and Landes goose; similarly, Nei's genetic distance varied between 0.25 and 0.75. However, the FST between the indigenous Chinese goose breeds was very small. In addition, genetic distance estimate, phylogenic, and cluster analyses of the genetic relationships and population structure revealed that some indigenous goose breeds had hybridized more frequently, resulting in a loss of genetic distinctiveness.


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