Genetic diversity and genetic differentiation in Echinococcus granulosus (Batsch, 1786) from domestic and sylvatic hosts on the mainland of Australia

Parasitology ◽  
1990 ◽  
Vol 101 (2) ◽  
pp. 283-289 ◽  
Author(s):  
A. J. Lymbery ◽  
R. C. A. Thompson ◽  
R. P. Hobbs
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Echinococcus Granulosus ◽  
Enzyme Electrophoresis ◽  
Rostellar Hook ◽  
Eastern Australia

Enzyme electrophoresis was used to examine genetic variation within and between populations of Echinococcus granulosus from domestic and sylvatic hosts in western and eastern Australia. Substantial genetic diversity was found within all populations. There was no evidence, however, of genetic differentiation between populations from different hosts or geographic areas. When isolates were grouped into previously described domestic or sylvatic strains on the basis of rostellar hook morphology, most (94%) of the genetic variation occurred within, rather than between strains. These results conflict with the currently accepted theory of separate domestic and sylvatic strains of E. granulosus on the mainland of Australia.

scholarly journals Evolutionary history and genetic connectivity across highly fragmented populations of an endangered daisy

Heredity ◽  
2021 ◽  
Author(s):  
Yael S. Rodger ◽  
Alexandra Pavlova ◽  
Steve Sinclair ◽  
Melinda Pickup ◽  
Paul Sunnucks
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Differentiation ◽  
Evolutionary History ◽  
Livestock Grazing ◽  
Genetic Connectivity ◽  
Evolutionary Divergence ◽  
Common Component ◽  
A Genome ◽  
Eastern Australia

AbstractConservation management can be aided by knowledge of genetic diversity and evolutionary history, so that ecological and evolutionary processes can be preserved. The Button Wrinklewort daisy (Rutidosis leptorrhynchoides) was a common component of grassy ecosystems in south-eastern Australia. It is now endangered due to extensive habitat loss and the impacts of livestock grazing, and is currently restricted to a few small populations in two regions >500 km apart, one in Victoria, the other in the Australian Capital Territory and nearby New South Wales (ACT/NSW). Using a genome-wide SNP dataset, we assessed patterns of genetic structure and genetic differentiation of 12 natural diploid populations. We estimated intrapopulation genetic diversity to scope sources for genetic management. Bayesian clustering and principal coordinate analyses showed strong population genetic differentiation between the two regions, and substantial substructure within ACT/NSW. A coalescent tree-building approach implemented in SNAPP indicated evolutionary divergence between the two distant regions. Among the populations screened, the last two known remaining Victorian populations had the highest genetic diversity, despite having among the lowest recent census sizes. A maximum likelihood population tree method implemented in TreeMix suggested little or no recent gene flow except potentially between very close neighbours. Populations that were more genetically distinctive had lower genetic diversity, suggesting that drift in isolation is likely driving population differentiation though loss of diversity, hence re-establishing gene flow among them is desirable. These results provide background knowledge for evidence-based conservation and support genetic rescue within and between regions to elevate genetic diversity and alleviate inbreeding.

Genetic polymorphism in Proteocephalus exiguus shown by enzyme electrophoresis

1996 ◽  
Vol 70 (4) ◽  
pp. 345-349 ◽  
Author(s):  
V. Šnábel ◽  
V. Hanzelová ◽  
S. Mattiucci ◽  
S. D'Amelio ◽  
L. Paggi
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Polymorphism ◽  
Genetic Variability ◽  
Balancing Selection ◽  
Outcrossing Rate ◽  
Enzyme Electrophoresis ◽  
Factors Affecting ◽  
Hardy Weinberg Equilibrium ◽  
Coregonid Fishes

AbstractEnzyme electrophoresis has been used to examine genetic diversity in a population of Proteocephalus exiguus La Rue, 1911 (Cestoda: Proteocephalidae), parasitizing salmonid and coregonid fishes. Among 16 loci tested, three polymorphic loci (Ada, Got, Pgm-2) were found. Six different genotypes at the Got locus distributed in Hardy-Weinberg equilibrium suggest remarkable genetic flexibility of P. exiguus. Balancing selection is proposed as the mechanism maintaining genetic variation within the species. Data of genetic variability parameters (Ho = 0.064; He = 0.07; P = 0.19) and outcrossing rate (t = 0.842) of P. exiguus population have been provided. Possible factors affecting these data are discussed.

Genetic diversity and differentiation in populations of Japanese stone pine (Pinuspumila) in Japan

1996 ◽  
Vol 26 (8) ◽  
pp. 1454-1462 ◽  
Author(s):  
Naoki Tani ◽  
Nobuhiro Tomaru ◽  
Masayuki Araki ◽  
Kihachiro Ohba
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Phylogenetic Trees ◽  
Genetic Relationships ◽  
Natural Populations ◽  
Group Method ◽  
Stone Pine ◽  
Arithmetic Means ◽  
Pair Group

Japanese stone pine (Pinuspumila Regel) is a dominant species characteristic of alpine zones of high mountains. Eighteen natural populations of P. pumila were studied in an effort to determine the extent and distribution of genetic diversity. The extent of genetic diversity within this species was high (HT = 0.271), and the genetic differentiation among populations was also high (GST = 0.170) compared with those of other conifers. In previous studies of P. pumila in Russia, the genetic variation within the species was also high, but the genetic differentiation among populations was low. We infer that this difference originates from differences in geographic distribution and ecological differences between the two countries. The genetic variation within each population tended, as a whole, to be smaller within marginal southern populations than within northern populations. Genetic relationships among populations reflect the geographic locations, as shown by unweighted pair-group method with arithmetic means and neighbor-joining phylogenetic trees.

Genetic variation within and relationships among five subpopulations of Slovak Thoroughbred

2004 ◽  
Vol 52 (3) ◽  
pp. 259-265
Author(s):  
Daniela Šátková-Jakabová ◽  
J. Trandžík ◽  
Ľudmila Hudecová-Kvasňáková ◽  
Erika Hegedüšová-Zetochová ◽  
A. Bugarský ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
International Society ◽  
Microsatellite Loci ◽  
Genetic Relationships ◽  
Allele Frequencies ◽  
Weinberg Equilibrium ◽  
Hardy Weinberg Equilibrium

Genetic variation at six microsatellite loci was analysed for five Thoroughbred subpopulations to determine the magnitude of genetic differentiation and the genetic relationships among the subpopulations. Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, with all subpopulations. The genetic diversities and relationships of five Thoroughbred subpopulations were evaluated using six microsatellites recommended by the International Society of Animal Genetics (ISAG). The allele frequencies, the effective numbers of alleles, and the observed and expected heterozygosities were calculated. POPGENE v. 1.31 (Yeh et al., 1997) was used to test for deviations from the Hardy-Weinberg (H-W) equilibrium and to assign FIS estimates (Weir, 1990). The utility of microsatellites for evaluating genetic diversity of horses is discussed.

Limited Genetic Diversity and High Differentiation in Angelica Dahurica Resulted by Domestication: Insights to Breeding and Conservation

2021 ◽  
Author(s):  
Rong Huang ◽  
Yinrong Liu ◽  
Jianling Chen ◽  
Zuyu Lu ◽  
Jiajia Wang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Clustering Analysis ◽  
Large Scale ◽  
Angelica Dahurica ◽  
Significant Genetic Differentiation ◽  
Large Scale Analysis ◽  
Domestication Process ◽  
Resources Conservation

Abstract Background： Angelica dahurica, belonging to the Apiaceae family, whose dry root is a famous traditional Chinese medicine named as “Bai zhi”. There are two cultivars (A. dahurica cv. ‘Hangbaizhi’ and A. dahurica cv. ‘Qibaizhi’), which have been domesticated for thousands of years. Long term artificial selection has led to great changes in root phenotypes of the two cultivars, and also decreased their adaptability to environment. We proposed hypothesis that the cultivars may lose some genetic diversity and highly differentiate from wild A. dahurica during the domestication process. However, few studies have been carried out on how domestication affects the genetic variation of this species. Here, we accessed the levels of genetic variation and differentiation within and between wild A. dahurica and its cultivars using 12 SSR markers. Results: The results revealed that the genetic diversity of the cultivars was much lower than that of wild A. dahurica, and A. dahurica cv. ‘Qibaizhi’ had lower genetic diversity compared to A. dahurica cv. ‘Hangbaizhi’. AMOVA analysis showed significant genetic differentiation between the wild and cultivated A. dahurica, and between A. dahurica cv. ‘Hangbaizhi’ and A. dahurica cv. ‘Qibaizhi’. The results of Bayesian, UPGMA, NJ and PcoA clustering analysis indicated that all 15 populations were assigned to two genetic clusters corresponding to the wild and cultivated resources. Bayesian clustering analysis further divided the cultivated resources into two sub-clusters corresponding to the two cultivars. Conclusions：Our study suggests that domestication process is likely the major factor resulting in the loss of genetic diversity in cultivated A. dahurica and significant genetic differentiation from the wild resources due to founder effect and/or artificially directional selections. This large-scale analysis of population genetics could provide valuable information for genetic resources conservation and breeding programs of Angelica dahurica.

scholarly journals Genetic diversity and population structure of Eurycoma apiculata in Eastern Sumatra, Indonesia

2021 ◽  
Vol 22 (10) ◽  
Author(s):  
Zulfahmi Zulfahmi ◽  
Parjanto Parjanto ◽  
Edi Purwanto ◽  
Ahmad Yunus
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Gene Diversity ◽  
In Situ Conservation ◽  
Genetic Material ◽  
Ex Situ ◽  
Breeding Programs ◽  
The Mean

Abstract. Zulfahmi, Parjanto, Purwanto E, Yunus A. 2021. Genetic diversity and population structure of Eurycoma apiculata in Eastern Sumatra, Indonesia. Biodiversitas 22: 4431-4439. Information on genetic variation within and among populations of Eurycoma apiculata plants is important to develop strategies for their conservation, sustainable use, and genetic improvement. To date, no information on genetic variation within and among populations of the E. apiculata has been reported. This study aims to assess genetic diversity within and among populations of E. apiculata based on RAPD markers, and to determine populations to collect E. apiculata genetic material for conservation and breeding programs. Young leaves of E. apiculata were collected from six natural populations. Fifteen RAPD primers were used to assess the genetic diversity of each population. The data obtained were analyzed with POPGEN and Arlequin software. The amplification results of 15 selected primers produced 3-16 loci with all primers 100% polymorphic. At the species level, the mean allele per locus (Na), number of effective alleles (Ne), percentage of polymorphic loci (PPL), Nei’s gene diversity index (He) and Shannon information index (I) were 2.000, 1.244, 100%, 0.167, and 0.286, respectively. At the population level, the mean values for Na, Ne, PPL, He and I were 1.393, 1.312, 39.27%, 0.119, and 0.186, respectively. The highest value of gene diversity within population (He) was found in the Lingga-1 population and the lowest value was found in the Rumbio population. The value of genetic differentiation among populations (GST) of E. apiculata is 0.284, consistent with the results of the AMOVA analysis which found that genetic variation among populations was 23.14%, indicates that the genetic variation of E. apiculata was more stored within populations than among populations. The gene flow (Nm) value of E. apiculata was 1.259 migrants per generation among populations. The Nm value of this species was high category, and could inhibit genetic differentiation among populations. The clustering of E. apiculata population based on the UPGMA dendrogram and PCA was inconsistent with its geographic distribution, reflecting the possibility that genes migration occurred between islands in the past. The main finding of this study was the genetic variation of the E. apiculata mostly stored within the population. Therefore, the population with the highest genetic diversity is a priority for in-situ conservation, and collection of E. apiculata genetic material for ex-situ conservation and breeding programs should be carried out minimum from Lingga-1 and Pokomo populations.

Conservation genetics of Hill’s thistle (Cirsium hillii)

Botany ◽  
2010 ◽  
Vol 88 (12) ◽  
pp. 1073-1080 ◽  
Author(s):  
Joanna R. Freeland ◽  
Joy Gillespie ◽  
Claudia Ciotir ◽  
Marcel E. Dorken
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Habitat Loss ◽  
Perennial Herb ◽  
Great Lakes Region ◽  
Species At Risk ◽  
Foreseeable Future ◽  
Species Combination ◽  
Private Alleles

Populations at the edges of their geographical ranges are often characterized by reduced genetic diversity and increased genetic differentiation. These patterns may be exacerbated by specialized associations between plants and uncommon habitats. Together, reduced diversity and increased subdivision may increase the risk of population extirpation, an issue that is particularly important for plants classified as rare or threatened. Hill’s thistle (Cirsium hillii (Canby) Fernald), is a perennial herb endemic to the Great Lakes region and is considered threatened in Canada where its northernmost distribution occurs. We used microsatellite markers to genotype plants from 11 populations of Hill’s thistle that span the range of the species distribution within Canada. These data were used to investigate levels of genetic diversity within populations and genetic differentiation between populations, and to evaluate associations between patterns of genetic variation and those expected under ongoing habitat loss. Genetic differentiation among populations was low, although significant pairwise FST values, along with the presence of private alleles in most populations, was consistent with moderate to low gene flow. Nevertheless, in comparison with a congeneric rare species (Cirsium pitcheri) that occurs in the same geographical region in Canada, genetic diversity within most populations was high, and we suggest that this is at least partially attributable to this species’ combination of sexual and clonal reproduction. Despite high levels of genetic diversity, Hill’s thistle should probably remain a designated species at risk because of ongoing habitat loss; however, our data suggest that Hill’s thistle is unlikely to suffer from reduced genetic diversity in the foreseeable future.

scholarly journals High Genetic Diversity and Insignificant Interspecific Differentiation inOpisthopappusShih, an Endangered Cliff Genus Endemic to the Taihang Mountains of China

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Rongmin Guo ◽  
Lihua Zhou ◽  
Hongbo Zhao ◽  
Fadi Chen
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Species Level ◽  
Endangered Plants ◽  
High Genetic Diversity ◽  
Fragmented Distribution ◽  
Polymorphic Bands ◽  
Genetic Structures ◽  
Different Levels

OpisthopappusShih is endemic to the Taihang Mountains, China. It grows in the crevice of cliffs and is in fragmented distribution. This genus consists of two species, namely,O. taihangensis(Ling) Shih andO. longilobusShih, which are both endangered plants in China. This study adopted intersimple sequence repeat markers (ISSR) to analyze the genetic diversity and genetic structure from different levels (genus, species, and population) in this genus. A total of 253 loci were obtained from 27 primers, 230 of which were polymorphic loci with a proportion of polymorphic bands (PPB) of up to 90.91% at genus level. At species level, bothO. taihangensis(PPB=90.12%,H=0.1842, andI=0.289) andO. longilobus(PPB=95.21%,H=0.2226, andI=0.3542) have high genetic diversity. Their respective genetic variation mostly existed within the population. And genetic variation inO. longilobus(84.95%) was higher than that inO. taihangensis(80.45%). A certain genetic differentiation among populations inO. taihangensiswas found (Gst=0.2740,Φst=0.196) and genetic differentiation inO. longilobuswas very small (Gst=0.1034,Φst=0.151). Gene flow in different degrees (Nm=1.325and 4.336, resp.) and mating system can form the existing genetic structures of these two species. Furthermore, genetic differentiation coefficient (Gst=0.0453) between species and the clustering result based on the genetic distance showed that interspecific differentiation betweenO. taihangensisandO. longilobuswas not significant and could occur lately.

Prominent genetic structure across native and introduced ranges of Pluchea indica, a mangrove associate, as revealed by microsatellite markers

2020 ◽  
Vol 13 (3) ◽  
pp. 341-353
Author(s):  
Yuting Lin ◽  
Achyut Kumar Banerjee ◽  
Haidan Wu ◽  
Fengxiao Tan ◽  
Hui Feng ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Variation ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Spatial Scales ◽  
Large Spatial Scale ◽  
Introduced Range ◽  
Native And Introduced Ranges ◽  
Mangrove Associate

Abstract Aims Pluchea indica is a mangrove-associate species, known for its medicinal properties in its native range and being invasive in part of its introduced range. This study aimed to assess geographic distribution of genetic variation of this species across its distribution range, identify the factors influencing its genetic structure and use this information to suggest conservation and management strategies in its native and introduced ranges, respectively. Methods We assessed the genetic diversity and population structure of 348 individuals from 31 populations across its native (Asia) and introduced (USA) ranges for 15 nuclear microsatellite loci. The spatial pattern of genetic variation was investigated at both large and regional spatial scales with the hypothesis that geographic distance and natural geographic barriers would influence the population structure with varying levels of differentiation across spatial scales. Important Findings We found relatively high genetic diversity at the population level and pronounced genetic differentiation in P. indica, as compared with the genetic diversity parameters of mangroves and mangrove associates in this region. Most of the populations showed heterozygote deficiency, primarily due to inbreeding and impediment of gene flow. Analysis of population structures at large spatial scale revealed the presence of two major clusters across the species’ natural range separating populations in China from those in Indonesia, Malaysia, Singapore, Thailand, Cambodia and Philippines, and that the USA population might have been introduced from the population cluster in China. Genetic differentiation between populations was also observed at the regional scale. A large number of populations showed evidence of genetic bottleneck, thereby emphasizing the risk of local extinction. Based on these findings, our study recommends in situ conservation strategies, such as to prioritize populations for conservation actions and to maintain genetic diversity.

scholarly journals Genetic Variation in Turkish Red Pine (Pinus brutia Ten.) Seed Stands as Determined by RAPD Markers

2004 ◽  
Vol 53 (1-6) ◽  
pp. 169-175 ◽  
Author(s):  
G. Eren Kandedmir ◽  
I. Kandemir ◽  
Zeki Kaya
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Differentiation ◽  
Rapd Marker ◽  
Red Pine ◽  
Anthropogenic Factors ◽  
Pinus Brutia ◽  
Turkish Red Pine ◽  
The Impact ◽  
Seed Stand

SummaryTurkish red pine (Pinus brutia Ten.) is one of the important tree species in Turkey. The species has been heavily disturbed by anthropogenic factors and fire, making it important to understand the magnitude of the impact on genetic diversity of areas reserved for seed production. To explore the extent of genetic variation in Turkish red pine seed stands, a random amplified polymorphic DNA (RAPD) marker system was used in the study. The estimated genic diversity for seed stands was found to range from H =0.17 (P, %of polymorphic loci =%58.7) in Çameli-Göldağ to 0.29 (P =%81.7) in Bayramiç-Karaköy seed stand though the lowest polymorphism was observed in Fındıkpınarı seed stand (P =55.8%). The total gene diversity was calculated as HT=0.34, in Turkish red pine. About 65% of the total diversity was within seed stands. No distinct pattern of genetic diversity was found according to the geography, elevation or breeding zones. The highest genetic differentiation was found in the Western Mediterranean geographic region, however, within population genetic diversity was found to be similar among different geographic regions (HS=0.22-0.24). GSTvalue calculated was high (0.35) indicating that genetic differentiation among the studied seed stands was substantial. Dendrogram constructed with genetic distance data did not yield a firm pattern with respect to geography, elevation and breeding zones. In fact, the most of the clusters in the dendrogram had very low bootstrap values, suggesting that the clusters could be refined if more populations and markers are included in the future studies. The implication of the results with respect to in situ conservation of genetic resources of the species was discussed.

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