scholarly journals GENETIC STRUCTURE AND DIFFERENTIATION OF SIBERIAN FIR POPULATIONS LOCATED AT VARIED ELEVATIONS IN WESTERN SAYAN

2005 ◽  
Vol 3 (2) ◽  
pp. 22-27
Author(s):  
Albina Y Larionova ◽  
Aleksandr K Ekart
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Elevation Gradient ◽  
High Mountain ◽  
Allozyme Diversity ◽  
Siberian Fir ◽  
Abies Sibirica ◽  
Western Sayan ◽  
Degree Of Differentiation ◽  
Diversity Structure

On the basis of analysis for 19 genes coding allozyme diversity of 11 enzymes (IDH, NDH, MDH, SKDH, FE, GDH, PGM, SOD, GOT, LAP, PGI) the data about genetic diversity, structure and degree of differentiation of Siberian fir populations (Abies sibirica Ledeb) located at varied elevations in Western Sayan (400 m, 1000 m and 1500 m) were obtained. It was established that the most significant differences at genetic structure are observed between distant from each other along an elevation gradient low mountain and high mountain populations.

scholarly journals Population Genetic Structure of Asclepias Tuberosa In Northwest Iowa: A Comparison Within and Between Remnant Prairies and Commercially Available Seed

2015 ◽  
Vol 122 (1-4) ◽  
pp. 1-6
Author(s):  
Jeffrey T Ploegstra ◽  
Brittany de Ruyter ◽  
Tony Jelsma
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Tallgrass Prairie ◽  
Microsatellite Analysis ◽  
Outbreeding Depression ◽  
Moderate Degree ◽  
Asclepias Syriaca ◽  
Minimal Impact ◽  
Low Degree ◽  
Degree Of Differentiation

Isolated in scattered remnants, less than 0.1% of Iowa's original tallgrass prairie remains. The small populations remaining are at risk for reduced genetic diversity, inbreeding depression, and outbreeding depression. In light of these concerns, we used microsatellite analysis to assess the genetic structure of butterfly milkweed (Asclepias tuberosa) populations on prairie remnants in northwest Iowa. We compared remnant populations with a restoration population at Dordt College in Sioux Center, Iowa, and with an Oklahoma seed source. Microsatellites identified for use in common milkweed (Asclepias syriaca) had sufficient polymorphism information content (PIC) across the butterfly milkweed (A. tuberosa) populations sampled (mean PIC = 0.624). The FIS values indicated a lack of inbreeding (mean FIS = −0.1455) even in the commercially expanded seed. The pairwise FST values showed a low degree of differentiation among the remnants (mean FST = 0.0453) but a moderate degree (mean FST = 0.105) of differentiation when comparing the remnants to the Dordt restoration or to seed from Oklahoma. Despite massive loss and fragmentation of the tallgrass prairie, our microsatellite analysis revealed no evidence of inbreeding in A. tuberosa. However, evidence of genetic differentiation suggests that effort should be made to preserve the diversity still present. Seed expansion efforts appear to have had minimal impact on overall genetic diversity, although the diversity in particular selectable traits may be reduced. The differences between the genetics of the propagated seed at the Dordt restoration and the Oklahoma seed when compared to native remnants support the usefulness of source-identified seed.

scholarly journals Genetic diversity and spatial genetic structure in populations of Orbignya phalerata Mart. under different exploitation intensities in the Brazilian savanna

2015 ◽  
Vol 64 (1-6) ◽  
pp. 201-211 ◽  
Author(s):  
Bruna Ibanes ◽  
A.M. Sebbenn ◽  
V.C.R. Azevedo ◽  
M.A. Moreno ◽  
F.B. Gandara ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Spatial Genetic Structure ◽  
Spatial Distance ◽  
Null Alleles ◽  
Fixation Index ◽  
Genetic Studies ◽  
Expected Heterozygosity ◽  
Adult Trees ◽  
Diversity Structure

Abstract Genetic studies in tropical tree species have found signs of decreased genetic diversity and increased levels of inbreeding and spatial genetic structure (SGS) in fragmented and exploited populations. The aim of this paper was to investigate genetic diversity, structure, and intrapopulation SGS using eight microsatellite loci for three Orbignya phalerata populations that have undergone different intensities of seed harvesting. From each population, we georeferenced and sampled 30 seedlings, 30 juveniles, and 30 adult trees. The total number of alleles over all loci (k), and observed (Ho) and expected heterozygosity (He) presented lower values for the population experiencing more intense fruit harvesting than less heavily exploited populations, suggesting that fruit harvesting may decrease genetic diversity. Null alleles were detected in practically all loci among seedlings, juveniles, and adults in all populations, indicating that the estimates of Ho, He, and fixation index (F) are biased. When corrected for null alleles (FNull), the fixation index decreased for all samples, resulting in significantly higher than zero results for seedlings of all populations, but not for juveniles and adults of all populations. The comparison of FNull values between cohorts in the most heavily exploited population (ESP) suggests that inbred individuals are eliminated between seedling and adult stages. Significant SGS was detected up to 60 m in all populations, which indicates short distance seed dispersal. Genetic differentiation (G’ST) between pairwise populations was related to spatial distance between populations, with the greatest difference between more distant populations.

scholarly journals Study on the Genetic Structure Based on Geographic Populations of the Endangered Tree Species: Liriodendron chinense

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 917
Author(s):  
Peng-Yan Zhou ◽  
Li-Xing Hui ◽  
Shu-Jing Huang ◽  
Zhou-Xian Ni ◽  
Fa-Xin Yu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Natural Populations ◽  
Systematic Research ◽  
Endangered Tree ◽  
Endangered Tree Species ◽  
Expected Heterozygosity ◽  
Liriodendron Chinense ◽  
Geographic Populations ◽  
Degree Of Differentiation

Liriodendron chinense (Hemsley) Sargent is a Class II protected plant in China as natural populations are on the verge of extinction. There is still a lack of systematic research on the genetic resources of its geographic populations. In this study, we used 20 pairs of SSR markers with high polymorphism to analyze a total of 808 L. chinense samples from 22 regions, and 63 Liriodendron tulipifera Linn samples from 2 regions were used as a comparison group. The results revealed a total of 78 alleles in L. chinense, and the average expected heterozygosity (He) was 0.558, showing a low level of genetic diversity. The degree of differentiation of L. chinense was high, with the differentiation coefficient (Fst) as high as 0.302, which is related to the low gene flow (Nm = 0.578). Based on the genetic structure, principal coordinate analysis (PCoA) and phylogenetic analysis of 24 Liriodendron spp. populations, L. chinense and L. tulipifera had obvious differentiation, while the differentiation between L. chinense geographic populations was very large and irregular. Inbreeding appears within the geographic populations, and the level of genetic diversity is very low. In order to protect the genetic diversity of L. chinense, in addition to protecting the existing population as much as possible, artificial cultivation should introduce materials from multiple populations.

Genetic diversity and genetic structure of the rare and endangered species, Primula ranunculoides

2014 ◽  
Vol 21 (5) ◽  
pp. 601-609
Author(s):  
Wang Deyun ◽  
Peng Jie ◽  
Chen Yajing ◽  
Lü Guosheng ◽  
Zhang Xiaoping ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Endangered Species ◽  
Rare And Endangered Species ◽  
Rare And Endangered

scholarly journals The Patterns and Puzzles of Genetic Diversity of Endangered Freshwater Mussel Unio crassus Philipsson, 1788 Populations from Vistula and Neman Drainages (Eastern Central Europe)

Life ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 119
Author(s):  
Adrianna Kilikowska ◽  
Monika Mioduchowska ◽  
Anna Wysocka ◽  
Agnieszka Kaczmarczyk-Ziemba ◽  
Joanna Rychlińska ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Spatial Scales ◽  
Freshwater Mussel ◽  
Its Region ◽  
Strong Relationship ◽  
Mantel Test ◽  
Freshwater Ecosystems ◽  
Hierarchical Organization ◽  
Anthropogenic Factors

Mussels of the family Unionidae are important components of freshwater ecosystems. Alarmingly, the International Union for Conservation of Nature and Natural Resources Red List of Threatened Species identifies almost 200 unionid species as extinct, endangered, or threatened. Their decline is the result of human impact on freshwater habitats, and the decrease of host fish populations. The Thick Shelled River Mussel Unio crassus Philipsson, 1788 is one of the examples that has been reported to show a dramatic decline of populations. Hierarchical organization of riverine systems is supposed to reflect the genetic structure of populations inhabiting them. The main goal of this study was an assessment of the U. crassus genetic diversity in river ecosystems using hierarchical analysis. Different molecular markers, the nuclear ribosomal internal transcribed spacer ITS region, and mitochondrial DNA genes (cox1 and ndh1), were used to examine the distribution of U. crassus among-population genetic variation at multiple spatial scales (within rivers, among rivers within drainages, and between drainages of the Neman and Vistula rivers). We found high genetic structure between both drainages suggesting that in the case of the analyzed U. crassus populations we were dealing with at least two different genetic units. Only about 4% of the mtDNA variation was due to differences among populations within drainages. However, comparison of population differentiation within drainages for mtDNA also showed some genetic structure among populations within the Vistula drainage. Only one haplotype was shared among all Polish populations whereas the remainder were unique for each population despite the hydrological connection. Interestingly, some haplotypes were present in both drainages. In the case of U. crassus populations under study, the Mantel test revealed a relatively strong relationship between genetic and geographical distances. However, in detail, the pattern of genetic diversity seems to be much more complicated. Therefore, we suggest that the observed pattern of U. crassus genetic diversity distribution is shaped by both historical and current factors i.e. different routes of post glacial colonization and history of drainage systems, historical gene flow, and more recent habitat fragmentation due to anthropogenic factors.

scholarly journals Impact of cyclones on hard coral and metapopulation structure, connectivity and genetic diversity of coral reef fish

Coral Reefs ◽  
2021 ◽  
Author(s):  
Gabriele Gerlach ◽  
Philipp Kraemer ◽  
Peggy Weist ◽  
Laura Eickelmann ◽  
Michael J. Kingsford
Keyword(s):  
Genetic Diversity ◽  
Coral Reef ◽  
Genetic Structure ◽  
Reef Fish ◽  
Coral Reef Fish ◽  
Population Genetic Study ◽  
Hard Coral ◽  
Great Loss ◽  
Metapopulation Structure ◽  
The Impact

AbstractCyclones have one of the greatest effects on the biodiversity of coral reefs and the associated species. But it is unknown how stochastic alterations in habitat structure influence metapopulation structure, connectivity and genetic diversity. From 1993 to 2018, the reefs of the Capricorn Bunker Reef group in the southern part of the Great Barrier Reef were impacted by three tropical cyclones including cyclone Hamish (2009, category 5). This resulted in substantial loss of live habitat-forming coral and coral reef fish communities. Within 6–8 years after cyclones had devastated, live hard corals recovered by 50–60%. We show the relationship between hard coral cover and the abundance of the neon damselfish (Pomacentrus coelestis), the first fish colonizing destroyed reefs. We present the first long-term (2008–2015 years corresponding to 16–24 generations of P. coelestis) population genetic study to understand the impact of cyclones on the meta-population structure, connectivity and genetic diversity of the neon damselfish. After the cyclone, we observed the largest change in the genetic structure at reef populations compared to other years. Simultaneously, allelic richness of genetic microsatellite markers dropped indicating a great loss of genetic diversity, which increased again in subsequent years. Over years, metapopulation dynamics were characterized by high connectivity among fish populations associated with the Capricorn Bunker reefs (2200 km2); however, despite high exchange, genetic patchiness was observed with annual strong genetic divergence between populations among reefs. Some broad similarities in the genetic structure in 2015 could be explained by dispersal from a source reef and the related expansion of local populations. This study has shown that alternating cyclone-driven changes and subsequent recovery phases of coral habitat can greatly influence patterns of reef fish connectivity. The frequency of disturbances determines abundance of fish and genetic diversity within species.

Genetic diversity of the extremely rare Habenaria dentata and the rare Habenaria linearifolia (Orchidaceae) in South Korea: implications for population history and conservation

2018 ◽  
Vol 151 (1) ◽  
pp. 48-60
Author(s):  
Mi Yoon Chung ◽  
Hoa Thi Quynh Le ◽  
Sungwon Son ◽  
Huai Zhen Tian ◽  
Myong Gi Chung
Keyword(s):  
Genetic Diversity ◽  
Southern China ◽  
Geographic Location ◽  
Population History ◽  
Population Variation ◽  
Conservation Strategies ◽  
Ancestral Population ◽  
Allozyme Diversity ◽  
Glacial Origin

Background and aims – Since historical events often leave an indelible mark on levels of genetic diversity of plant populations, one may indirectly infer their evolutionary history with the help of current patterns of genetic diversity. The terrestrial orchid Habenaria dentata, an element of warm-temperate/subtropical vegetation, reaches its northernmost limits in the Korean Peninsula, and thus it is extremely rare there. As H. dentata was absent from the Peninsula during the Last Glacial Maximum (LGM), it is likely to be of post-glacial origin having arrived from either a single refugium or multiple refugia. However, its rare, temperate/boreal congener H. linearifolia might have persisted in situ in either macrorefugia or microrefugia on the Peninsula during the LGM.Methods – To test which hypothesis is most appropriate for each species, we investigated levels of allozyme-based (17 loci) genetic diversity and population genetic structure in the two only known populations of H. dentata and in 12 populations of H. linearifolia.Key results – No allozyme diversity was found in H. dentata (He = 0.000), whereas H. linearifolia exhibited low within-population variation (He = 0.060) and high among-population differentiation (FST = 0.237). We found little association between populations in relation to their geographic location; several populations presented individuals belonging to different clusters.Conclusions – Our results suggest that H. dentata likely originated from a single ancestral population (perhaps from southern Japan or southern China) through post-glacial dispersal, whereas H. linearifolia probably survived the LGM in situ in microrefugia situated at low to mid-elevated regions. We further suggest that separate conservation strategies for each species should be employed, given that the two taxa have different ecological and demographic traits and harbour different levels of genetic diversity.

scholarly journals Effects of habitat structure and land-use intensity on the genetic structure of the grasshopper species Chorthippus parallelus

2014 ◽  
Vol 1 (2) ◽  
pp. 140133 ◽  
Author(s):  
Kerstin R. Wiesner ◽  
Jan Christian Habel ◽  
Martin M. Gossner ◽  
Hugh D. Loxdale ◽  
Günter Köhler ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Land Use ◽  
Genetic Structure ◽  
Sampling Site ◽  
Land Use Intensity ◽  
Habitat Size ◽  
Grasshopper Species ◽  
Chorthippus Parallelus ◽  
Landscape Characteristics ◽  
Local Populations

Land-use intensity (LUI) is assumed to impact the genetic structure of organisms. While effects of landscape structure on the genetics of local populations have frequently been analysed, potential effects of variation in LUI on the genetic diversity of local populations have mostly been neglected. In this study, we used six polymorphic microsatellites to analyse the genetic effects of variation in land use in the highly abundant grasshopper Chorthippus parallelus . We sampled a total of 610 individuals at 22 heterogeneous grassland sites in the Hainich-Dün region of Central Germany. For each of these grassland sites we assessed habitat size, LUI (combined index of mowing, grazing and fertilization), and the proportion of grassland adjoining the sampling site and the landscape heterogeneity (the latter two factors within a 500 m buffer zone surrounding each focal site). We found only marginal genetic differentiation among all local populations and no correlation between geographical and genetic distance. Habitat size, LUI and landscape characteristics had only weak effects on most of the parameters of genetic diversity of C. parallelus ; only expected heterozygosity and the grasshopper abundances were affected by interacting effects of LUI, habitat size and landscape characteristics. The lack of any strong relationships between LUI, abundance and the genetic structure might be due to large local populations of the species in the landscape, counteracting local differentiation and potential genetic drift effects.

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