scholarly journals Morphological and Isozyme Variation in Natural Populations of the Genus Medicago L. Prospected in Northern Algeria

2015 ◽  
Vol 43 (1) ◽  
pp. 86-95 ◽  
Author(s):  
Imane MEDOUKALI ◽  
Ines BELLIL ◽  
Douadi KHELIFI
Keyword(s):  
Genetic Diversity ◽  
Natural Populations ◽  
Morphological Characteristics ◽  
Genetic Distances ◽  
Glutamate Oxaloacetate Transaminase ◽  
High Genetic Diversity ◽  
Isozyme Markers ◽  
Northern Algeria ◽  
Isozyme Variability ◽  
High Level

As part of the evaluation and enhancement of genetic resources, morphological and isozyme variability within and among 169 accessions, representing 14 species of the genus Medicago L. collected in northern Algeria, was assessed using twelve quantitative traits and two enzymatic systems. Phenotype frequencies were scored in six enzyme zones to determine isozyme variability within and among populations. The data analysis resolved a high level of genetic diversity. Ten morphometric characteristics contributed to the discrimination of the species. The relationship between the collection site environment and phenotypic characteristics was also studied. Esterase (EST) enzyme system was more polymorphic than glutamate oxaloacetate transaminase (GOT) system. Were scored 2 zones with 10 bands and 21 phenotypes for GOT (glutamate oxaloacetate transaminase) and 4 zones with 22 bands and 71 phenotypes for EST (esterase) Polymorphism index and Jaccard’s genetic distances revealed the existence of a high genetic diversity within and among the studied populations. The annual species M. polymorpha presented an intraspecific polymorphism index of 0.57, which was higher than all other species indices. Clustering of the species based on isozyme markers was in agreement with taxonomic criteria and showed no significant correlation with morphological characteristics. Conservation programs should take into account the level of genetic diversity within and between populations revealed by isozyme markers.

scholarly journals Genetic diversity and structure among natural populations of Mytilaria laosensis (Hamamelidaceae) revealed by microsatellite markers

2018 ◽  
Vol 67 (1) ◽  
pp. 93-98 ◽  
Author(s):  
Niu Yu ◽  
Jie Yuan ◽  
Guangtian Yin ◽  
Jinchang Yang ◽  
Rongsheng Li ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Geographic Distance ◽  
Natural Populations ◽  
Magnetic Bead ◽  
Mantel Test ◽  
High Genetic Diversity ◽  
Information Index ◽  
Genetic Diversity And Structure ◽  
High Level ◽  
Mytilaria Laosensis

Abstract Mytilaria laosensis is a fast-growing tropical broadleaf tree that is extensively used for wood production and has significant ecological benefits. To investigate the genetic diversity and population structure of M. laosensis, eight major natural popu­lations in China were analyzed by using simple sequence repeat (SSR) markers. A total of 88 microsatellite-containing fragments were obtained by the method of magnetic bead enrichment, among which 26 pairs of SSR primers were scree­ned out and used to generate a total of 190 alleles among 152 individuals. The average of observed number of alleles, Shannon’s information index and polymorphism information content per locus were 18.3, 1.1577 and 0.7759, respectively, implying a high level of genetic diversity in M. laosensis popu­lations. The variation within populations accounted for 81.74 % of total variation based on analysis of molecular variance. Clus­ter analysis divided the eight populations into four groups, among which five populations from the southern parts of Guangxi province were classified as one major group. Mantel test showed that there was highly significant correlation bet­ween Euclidean genetic distance and geographic distance, suggesting that geographic isolation contribute to the high genetic diversity of M. laosensis. Together, these could provide support for the feasibility of exploration and utilization of M. laosensis in subtropical areas of East Asia including Jiangxi, Hunan and Fujian province of China.

scholarly journals Assessment of AFLP-Based Genetic Variation in the Populations of Picea asperata

2005 ◽  
Vol 54 (1-6) ◽  
pp. 24-30 ◽  
Author(s):  
X. Xue ◽  
Y. Wang ◽  
H. Korpelainen ◽  
C. Li
Keyword(s):  
Genetic Diversity ◽  
Population Genetic ◽  
Unbiased Estimate ◽  
Natural Populations ◽  
Genetic Distances ◽  
Western China ◽  
Picea Asperata ◽  
Limited Gene Flow ◽  
The Mean ◽  
High Level

Summary Picea asperata Mast., which occurs in a restricted habitat in western China, has a wide ecological amplitude. In the present study, ten natural populations of P. asperata were studied using AFLP markers to investigate the population genetic structure and the level of genetic diversity. Of the 210 loci identified with two EcoRI/MseI primer combinations, 142 loci were found to be polymorphic. Yet, the level of genetic diversity observed within populations was quite low. The averages of NEI’s gene diversities (h) and Shannon's indices of diversity (I) calculated across populations equaled 0.156 and 0.227, respectively. The coefficient of gene differentiation among populations, based on the estimate GST and the unbiased estimate Φst, equaled 0.340 and 0.231, respectively. The mean genetic distance (D) between population pairs was 0.119 (range 0.050-0.156). Such high values indicate that there is significant differentiation among populations of P. asperata. Several factors could have contributed to the strong population differentiation, including relatively limited gene flow between populations (Nm = 0.968). Variation in environmental conditions and consequent selection pressures may be other factors attributing to the high level of genetic differentiation among populations. In addition, it was discovered that the geographic distances are not correlated with the genetic distances between the populations of P. asperata.

scholarly journals Microsatellite genotyping from faeces of Lontra longicaudis from southern Brazil

2009 ◽  
Vol 99 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Laura I. Weber ◽  
Cintia G. Hildebrand ◽  
Anderson Ferreira ◽  
Gustavo Pedarassi ◽  
José A. Levy ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Conservation Status ◽  
Significant Degree ◽  
Southern Brazil ◽  
High Genetic Diversity ◽  
Low Degree ◽  
Faecal Samples ◽  
High Level ◽  
Degree Of Differentiation ◽  
Lontra Longicaudis

A genetic study of the neotropical river otter Lontra longicaudis (Olfers, 1818), which has an unknown conservation status, was carried out at the Taim Ecological Station and the margins of the Vargas stream, Rio Grande do Sul, southern Brazil. Faecal samples were collected, and DNA was extracted using a silica-guanidine method. Five microsatellite loci were amplified using PCR with heterologous primers previously described for Lutra lutra (Linnaeus, 1758). Sixteen faecal samples out of 29 from Taim and 11 out of 14 from Vargas stream margins contained enough DNA for genetic analysis. A total of 49 different alleles were found at both localities, from which 18 were exclusively found in individuals from Taim and 17 were exclusives from Vargas individuals. The most common allele was the same at both locations for three loci (Lut715, Lut733, and Lut818). A high level of genetic diversity was found at both sites (NeTaim=4.1, HoTaim=0.299, HeTaim=0.681; NeVargas=4.9, HoVargas=0.355, HeVargas=0.724), being higher at the Vargas stream site. A high and significant level of heterozygote deficiency was observed at most loci according to the χ2 test. The homogeneity χ2 test (P<0.001) showed that there were significant differences in the allele frequencies between the two locations. Genotyping for more than one locus was possible in 81.5% of samples, from which only 37% were possible to genotype for more than three loci. A low degree of relatedness was found among individuals from Taim (R=0.055±0.310), but an even lower value of relatedness was found at the Vargas site (R= -0.285±0.440). The significant degree of differentiation (I=0.890; F ST=0.059) found between Taim and Vargas individuals suggests that there is more than one population of otters in the southern extreme of Brazil, which probably are associated with the water body systems found in this region, the Mirim and the Caiuvá/Flores/Mangueira Lagoons. The high genetic diversity and low relatedness found at the Vargas stream, lead us to believe that the Vargas stream may be acting as a corridor between these water bodies for otter dispersion.

scholarly journals Genetic diversity and differentiation in reef-buildingMilleporaspecies, as revealed by cross-species amplification of fifteen novel microsatellite loci

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2936 ◽  
Author(s):  
Caroline E. Dubé ◽  
Serge Planes ◽  
Yuxiang Zhou ◽  
Véronique Berteaux-Lecellier ◽  
Emilie Boissin
Keyword(s):  
Genetic Diversity ◽  
Microsatellite Markers ◽  
Microsatellite Loci ◽  
Natural Populations ◽  
454 Sequencing ◽  
Genetic Distances ◽  
Null Alleles ◽  
Future Research ◽  
Significant Linkage ◽  
Pacific Species

Quantifying the genetic diversity in natural populations is crucial to address ecological and evolutionary questions. Despite recent advances in whole-genome sequencing, microsatellite markers have remained one of the most powerful tools for a myriad of population genetic approaches. Here, we used the 454 sequencing technique to develop microsatellite loci in the fire coralMillepora platyphylla, an important reef-builder of Indo-Pacific reefs.We tested the cross-species amplification of these loci in five other species of the genusMilleporaand analysed its success in correlation with the genetic distances between species using mitochondrial 16S sequences. We succeeded in discovering fifteen microsatellite loci in our target speciesM. platyphylla,among which twelve were polymorphic with 2–13 alleles and a mean observed heterozygosity of 0.411. Cross-species amplification in the five otherMilleporaspecies revealed a high probability of amplification success (71%) and polymorphism (59%) of the loci. Our results show no evidence of decreased heterozygosity with increasing genetic distance. However, only one locus enabled measures of genetic diversity in the Caribbean speciesM. complanatadue to high proportions of null alleles for most of the microsatellites. This result indicates that our novel markers may only be useful for the Indo-Pacific species ofMillepora.Measures of genetic diversity revealed significant linkage disequilibrium, moderate levels of observed heterozygosity (0.323–0.496) and heterozygote deficiencies for the Indo-Pacific species. The accessibility to new polymorphic microsatellite markers for hydrozoanMilleporaspecies creates new opportunities for future research on processes driving the complexity of their colonisation success on many Indo-Pacific reefs.

scholarly journals High Genetic Diversity but Absence of Population Structure in Local Chickens of Sri Lanka Inferred by Microsatellite Markers

2021 ◽  
Vol 12 ◽  
Author(s):  
Amali Malshani Samaraweera ◽  
Ranga Liyanage ◽  
Mohamed Nawaz Ibrahim ◽  
Ally Mwai Okeyo ◽  
Jianlin Han ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Sri Lanka ◽  
Microsatellite Markers ◽  
Allelic Diversity ◽  
Genetic Distances ◽  
Population Substructure ◽  
High Genetic Diversity ◽  
Naked Neck ◽  
Local Chicken ◽  
Local Chickens

Local chicken populations belonging to five villages in two geographically separated provinces of Sri Lanka were analyzed using 20 microsatellite markers to determine the genetic diversity of local chickens. Population genetic parameters were estimated separately for five populations based on geographic locations and for eight populations based on phenotypes, such as naked neck, long legged, crested or crown, frizzle feathered, Giriraj, commercial layer, crossbreds, and non-descript chicken. The analysis revealed that there was a high genetic diversity among local chickens with high number of unique alleles, mean number of alleles per locus (MNA), and total number of alleles per locus per population. A total of 185 microsatellite alleles were detected in 192 samples, indicating a high allelic diversity. The MNA ranged from 8.10 (non-descript village chicken) to 3.50 (Giriraj) among phenotypes and from 7.30 (Tabbowa) to 6.50 (Labunoruwa) among village populations. In phenotypic groups, positive inbreeding coefficient (FIS) values indicated the existence of population substructure with evidence of inbreeding. In commercial layers, a high expected heterozygosity He = 0.640 ± 0.042) and a negative FIS were observed. The positive FIS and high He estimates observed in village populations were due to the heterogeneity of samples, owing to free mating facilitated by communal feeding patterns. Highly admixed nature of phenotypes was explained as a result of rearing many phenotypes by households (58%) and interactions of chickens among neighboring households (53%). A weak substructure was evident due to the mating system, which disregarded the phenotypes. Based on genetic distances, crown chickens had the highest distance to other phenotypes, while the highest similarity was observed between non-descript village chickens and naked neck birds. The finding confirms the genetic wealth conserved within the populations as a result of the breeding system commonly practiced by chicken owners. Thus, the existing local chicken populations should be considered as a harbor of gene pool, which can be readily utilized in developing locally adapted and improved chicken breeds in the future.

scholarly journals Genetic Diversity and Population Divergence of a Rare, Endemic Grass (Elymus breviaristatus) in the Southeastern Qinghai-Tibetan Plateau

2019 ◽  
Vol 11 (20) ◽  
pp. 5863 ◽  
Author(s):  
Qingqing Yu ◽  
Qian Liu ◽  
Yi Xiong ◽  
Yanli Xiong ◽  
Zhixiao Dong ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Tibetan Plateau ◽  
Isolation By Distance ◽  
Genetic Distances ◽  
Conservation Strategy ◽  
Conservation Strategies ◽  
Grass Species ◽  
Population Divergence ◽  
High Genetic Diversity ◽  
Widespread Species

Elymus breviaristatus is a grass species only distributed in the southeast of Qinghai-Tibetan Plateau (QTP), which has suffered from serious habitat fragmentation. Therefore, understanding patterns of genetic diversity within and among natural E. breviaristatus populations could provide insight for future conservation strategies. In this study, sequence-related amplified polymorphism markers were employed to investigate the genetic diversity and hierarchical structure of seven E. breviaristatus populations from QTP, China. Multiple measures of genetic diversity indicated that there is low to moderate genetic variation within E. breviaristatus populations, consistent with its presumed mating system. In spite of its rarity, E. breviaristatus presented high genetic diversity that was equivalent to or even higher than that of widespread species. Bayesian clustering approaches, along with clustering analysis and principal coordinate analysis partitioned the studied populations of E. breviaristatus into five genetic clusters. Differentiation coefficients (Fst, GST, etc.) and AMOVA analysis revealed considerable genetic divergence among different populations. BARRIER analyses indicated that there were two potential barriers to gene flow among the E. breviaristatus populations. Despite these patterns of differentiation, genetic distances between populations were independent of geographic distances (r = 0.2197, p = 0.2534), indicating little isolation by distance. Moreover, despite detecting a common outlier by two methods, bioclimatic factors (altitude, annual mean temperature, and annual mean precipitation) were not related to diversity parameters, indicating little evidence for isolation caused by the environment. These patterns of diversity within and between populations are used to propose a conservation strategy for E. breviaristatus.

Genetic structure and variability in Pinusstrobus in Quebec

1994 ◽  
Vol 24 (8) ◽  
pp. 1726-1733 ◽  
Author(s):  
J. Beaulieu ◽  
J.-P. Simon
Keyword(s):  
Genetic Diversity ◽  
Statistical Tests ◽  
Natural Populations ◽  
Genetic Distances ◽  
White Pine ◽  
Eastern White Pine ◽  
Improvement Program ◽  
Bonferroni Procedure ◽  
Natural Range ◽  
Very High

The level of genetic diversity of natural populations of eastern white pine (Pinusstrobus L.) from Quebec was estimated from allozyme variants of 18 loci coding 12 enzyme systems. On average, a white pine population was polymorphic at 50.6% of loci, had 1.96 alleles and 1.22 effective alleles per locus, and observed and expected heterozygosities of 0.176 and 0.180, respectively. The level of genetic diversity was lower in the populations of the St. Lawrence lowlands than in those of western Quebec. This observation will help in guiding the selection program of the eastern white pine improvement program under way in Quebec. Genetic differentiation among sampled populations was weak and accounted for only 2% of the total diversity. The estimate of gene flow was very high, resulting in low values for genetic distances among populations. Only one locus showed a heterogeneity of allelic frequencies among populations after the Bonferroni procedure was applied for simultaneous statistical tests. A cluster analysis based on genetic distances among populations revealed that the Anticosti and Abitibi populations, located at the limit of the natural range of white pine, were similar to populations from regions that were geographically the most distant.

There Is No Evidence of Geographical Patterning among Invasive Kentucky Bluegrass (Poa pratensis) Populations in the Northern Great Plains

Weed Science ◽  
2016 ◽  
Vol 64 (3) ◽  
pp. 409-420 ◽  
Author(s):  
Lauren A. Dennhardt ◽  
Edward S. DeKeyser ◽  
Sarah A. Tennefos ◽  
Steven E. Travers
Keyword(s):  
Genetic Diversity ◽  
Great Plains ◽  
Propagule Pressure ◽  
Poa Pratensis ◽  
Natural Populations ◽  
Kentucky Bluegrass ◽  
Grass Species ◽  
Northern Great Plains ◽  
Wild Populations ◽  
High Genetic Diversity

The study of colonizing and of dominant grass species is essential for prairie conservation efforts. We sought to answer how naturalized Kentucky bluegrass in the northern Great Plains has become successful in the last 20 yr despite its long history in the northern Great Plains. We tested for evidence of geographical differentiation using flow cytometry and microsatellite markers to ascertain the population genetics of Kentucky bluegrass. Across all tested wild populations, high levels of genetic diversity were detected along with moderate levels of structure. Mantel tests of geographical patterns were not significant. Using clonal assignment, we found two major clones that made up the majority of the tested wild populations. When we compared the wild individuals to pedigree cultivars, we found virtually no genetic overlap across all tests, which did not support our hypothesis of developed cultivars contributing to high genetic diversity in natural populations. Furthermore, DNA content tests indicated a narrow range in ploidy in wild populations compared with lawn cultivars, further supporting a hypothesis of divergence between wild and pedigree cultivars. These results indicate the recent invasion of Kentucky bluegrass in the northern Great Plains is not because of adaptation or propagule pressure, but rather likely an environmental or land use shift.

scholarly journals Simple Sequence Repeat Marker Analysis of Genetic Diversity among Progeny of a Biparental Mapping Population of Sweetpotato

HortScience ◽  
2015 ◽  
Vol 50 (8) ◽  
pp. 1143-1147 ◽  
Author(s):  
Benard Yada ◽  
Gina Brown-Guedira ◽  
Agnes Alajo ◽  
Gorrettie N. Ssemakula ◽  
Robert O.M. Mwanga ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Linkage Analysis ◽  
Ssr Markers ◽  
Simple Sequence Repeat ◽  
Polymorphic Information Content ◽  
Genetic Distances ◽  
Sequence Repeat ◽  
Population Improvement ◽  
High Level ◽  
Simple Sequence

Genetic diversity is critical in sweetpotato improvement as it is the source of genes for desired genetic gains. Knowledge of the level of genetic diversity in a segregating family contributes to our understanding of the genetic diversity present in crosses and helps breeders to make selections for population improvement and cultivar release. Simple sequence repeat (SSR) markers have become widely used markers for diversity and linkage analysis in plants. In this study, we screened 405 sweetpotato SSR markers for polymorphism on the parents and progeny of a biparental cross of New Kawogo × Beauregard cultivars. Thereafter, we used the informative markers to analyze the diversity in this population. A total of 250 markers were polymorphic on the parents and selected progeny; of these, 133 were informative and used for diversity analysis. The polymorphic information content (PIC) values of the 133 markers ranged from 0.1 to 0.9 with an average of 0.7, an indication of high level of informativeness. The pairwise genetic distances among the progeny and parents ranged from 0.2 to 0.9, and they were grouped into five main clusters. The 133 SSR primers were informative and are recommended for use in sweetpotato diversity and linkage analysis.

scholarly journals Using Random Amplified Polymorphic DNA to Assess Genetic Diversity and Structure of NaturalCalophyllum brasiliense(Clusiaceae) Populations in Riparian Forests

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Evânia Galvão Mendonça ◽  
Anderson Marcos de Souza ◽  
Fábio de Almeida Vieira ◽  
Regiane Abjaud Estopa ◽  
Cristiane Aparecida Fioravante Reis ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Random Amplified Polymorphic Dna ◽  
Natural Populations ◽  
Rio Grande ◽  
Shannon Index ◽  
High Genetic Diversity ◽  
Family Structures ◽  
Genetic Diversity And Structure ◽  
Kinship Coefficients

The objective of this study was to assess the genetic variability in two natural populations ofCalophyllum brasilienselocated along two different rivers in the state of Minas Gerais, Brazil, using RAPD molecular markers. Eighty-two polymorphic fragments were amplified using 27 primers. The values obtained for Shannon index (I) were 0.513 and 0.530 for the populations located on the margins of the Rio Grande and Rio das Mortes, respectively, demonstrating the high genetic diversity in the studied populations. Nei’s genetic diversity (He) was 0.341 for the Rio Grande population and 0.357 for the Rio das Mortes population. These results were not significantly different between populations and suggest a large proportion of heterozygote individuals within both populations. AMOVA showed that 70.42% of the genetic variability is found within populations and 29.58% is found among populations (ФST=0.2958). The analysis of kinship coefficients detected the existence of family structures in both populations. Average kinship coefficients between neighboring individuals were 0.053 (P<0.001) in Rio das Mortes and 0.040 (P<0.001) in Rio Grande. This could be due to restricted pollen and seed dispersal and the history of anthropogenic disturbance in the area. These factors are likely to contribute to the relatedness observed among these genotypes.

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