scholarly journals Global gene flow releases invasive plants from environmental constraints on genetic diversity

2020 ◽  
Vol 117 (8) ◽  
pp. 4218-4227 ◽  
Author(s):  
Annabel L. Smith ◽  
Trevor R. Hodkinson ◽  
Jesus Villellas ◽  
Jane A. Catford ◽  
Anna Mária Csergő ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Invasive Plants ◽  
Spatial Genetic Structure ◽  
Plantago Lanceolata ◽  
Research Network ◽  
Environmental Constraints ◽  
Long Distance ◽  
Precipitation Seasonality ◽  
The Impact

When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata. Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.

scholarly journals Genetic Structure and Geographical Differentiation of Larix sibirica Ledeb. in the Urals

Forests ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1401
Author(s):  
Nikita Chertov ◽  
Yulia Vasilyeva ◽  
Andrei Zhulanov ◽  
Yulia Nechaeva ◽  
Svetlana Boronnikova ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Forest Fragmentation ◽  
Spatial Genetic Structure ◽  
Siberian Larch ◽  
Larix Sibirica ◽  
Forest Steppe ◽  
Middle Urals ◽  
The Urals ◽  
The Impact

The Ural Mountains and the West Eurasian Taiga forests are one of the most important centers of genetic diversity for Larix sibirica Ledeb. Forest fragmentation negatively impacts forest ecosystems, especially due to the impact of their intensive use on the effects of climate change. For the preservation and rational use of forest genetic resources, it is necessary to carefully investigate the genetic diversity of the main forest-forming plant species. The Larix genus species are among the most widespread woody plants in the world. The Siberian larch (Larix sibirica, Pinaceae) is found in the forest, forest-tundra, tundra (Southern part), and forest-steppe zones of the North, Northeast, and partly East of the European part of Russia and in Western and Eastern Siberia; in the Urals, the Siberian larch is distributed fragmentarily. In this study, eight pairs of simple sequence repeat (SSR) primers were used to analyse the genetic diversity and population structure of 15 Siberian larch populations in the Urals. Natural populations in the Urals exhibit indicators of genetic diversity comparable to those of Siberia populations (expected heterozygosity, He = 0.623; expected number of alleles, Ne = 4017; observed heterozygosity, Ho = 0.461). Genetic structure analysis revealed that the examined populations are relatively highly differentiated (Fst = 0.089). Using various algorithms for determining the spatial genetic structure, the examined populations formed three groups according to geographical location. The data obtained are required for the development of species conservation and restoration programs, which are especially important in the Middle Urals, which is the region with strong forest fragmentation.

The impact of postglacial marine invasions on the genetic diversity of an obligate freshwater fish, the longnose dace (Rhinichthys cataractae), on the Quebec peninsula

2006 ◽  
Vol 63 (6) ◽  
pp. 1429-1438 ◽  
Author(s):  
Philippe Girard ◽  
Bernard Angers
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Spatial Genetic Structure ◽  
Freshwater Species ◽  
Postglacial Colonization ◽  
Genetic Structure Of Populations ◽  
Marine Invasions ◽  
Rhinichthys Cataractae ◽  
Mitochondrial Dna Variability ◽  
The Impact

Postglacial seas are expected to have had significant effects on the genetic structure of populations of obligate freshwater fishes. To assess this influence, mitochondrial DNA variability was evaluated in 32 populations of longnose dace (Rhinichthys cataractae) of the Quebec peninsula located within and outside of the maximum extent of marine invasions of the Champlain and Laflamme seas. Three clades of haplotypes diverging from one to two mutations were defined. Despite this low divergence, a clear and significant spatial genetic structure was observed outside of the extent of marine invasions. However, a higher genetic diversity was observed in populations located within the extent of marine invasions because of the admixture of these clades with an additional lineage restricted almost exclusively to those areas. The low genetic divergence between the main haplotypes suggests a single origin, despite the known presence of this species in various refuges. Marine invasions preventing entry to the peninsula, especially from Atlantic refuge, are proposed as a possible explanation to this particular result. This study is a relevant argument for integrating postglacial marine invasions into postglacial colonization models of freshwater species in the northeastern part of North America.

scholarly journals Patterns of Fine-Scale Spatial Genetic Structure and Pollen Dispersal in Giant Sequoia (Sequoiadendron giganteum)

Forests ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 61
Author(s):  
Rainbow DeSilva ◽  
Richard S. Dodd
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Spatial Genetic Structure ◽  
Spatial Scales ◽  
Pollen Dispersal ◽  
Detailed Examination ◽  
Background Information ◽  
Long Distance ◽  
Giant Sequoia ◽  
Sequoiadendron Giganteum

Research Highlights: Patterns of dispersal shape the distribution and temporal development of genetic diversity both within and among populations. In an era of unprecedented environmental change, the maintenance of extant genetic diversity is crucial to population persistence. Background and Objectives: We investigate patterns of pollen dispersal and spatial genetic structure within populations of giant sequoia (Sequoiadendron giganteum). Materials and Methods: The leaf genotypes of established trees from twelve populations were used to estimate the extent of spatial genetic structure within populations, as measured by the Sp statistic. We utilized progeny arrays from five populations to estimate mating parameters, the diversity of the pollen pool, and characteristics of pollen dispersal. Results: Our research indicates that giant sequoia is predominantly outcrossing, but exhibits moderate levels of bi-parental inbreeding (0.155). The diversity of the pollen pool is low, with an average of 7.5 pollen donors per mother tree. As revealed by the Sp-statistic, we find significant genetic structure in ten of twelve populations examined, which indicates the clustering of related individuals at fine spatial scales. Estimates of pollen and gene dispersal indicate predominantly local dispersal, with the majority of pollen dispersal <253 m, and with some populations showing fat-tailed dispersal curves, suggesting potential for long-distance dispersal. Conclusions: The research presented here represent the first detailed examination of the reproductive ecology of giant sequoia, which will provide necessary background information for the conservation of genetic resources in this species. We suggest that restoration planting can mitigate potential diversity loss from many giant sequoia populations.

Spatial genetic structure of a keystone long-lived semiarid shrub: historical effects prevail but do not cancel the impact of recent severe habitat loss on genetic diversity

2020 ◽  
Vol 21 (5) ◽  
pp. 853-867 ◽  
Author(s):  
Ana González-Robles ◽  
Antonio J. Manzaneda ◽  
Teresa Salido ◽  
Francisco Valera ◽  
Cristina García ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Habitat Loss ◽  
Spatial Genetic Structure ◽  
The Impact

scholarly journals Spatial Genetic Structure and Demographic History of the Wild Boar in the Qinling Mountains, China

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 346
Author(s):  
Chaochao Hu ◽  
Sijia Yuan ◽  
Wan Sun ◽  
Wan Chen ◽  
Wei Liu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Wild Boar ◽  
Spatial Genetic Structure ◽  
Demographic History ◽  
Haplotype Diversity ◽  
Phylogeographic Structure ◽  
Qinling Mountains ◽  
Wild Boars ◽  
The Impact

Species dispersal patterns and population genetic structure can be influenced by geographical features. Qinling Mountains (QM) provide an excellent area for phylogeographic study. The phylogeography of Asian-wide wild boars revealed the colonization route. However, the impact of the QM on genetic diversity, genetic structure and population origin is still poorly understood. In this study, genetic analysis of wild boar in the QM was conducted based on the mitochondrial control region (943 bp) and twelve microsatellite loci of 82 individuals in 16 sampling locations. Overall genetic haplotype diversity was 0.86, and the nucleotide diversity was 0.0079. A total of 17 new haplotypes were detected. The level of genetic diversity of wild boars in QM was lower than in East Asia, but higher than in Europe. Phylogenetic analysis showed the weak genetic divergence in QM. Mismatch analysis, neutrality tests, and Bayesian Skyline Plot (BSP) results revealed that the estimates of effective population size were under demographic equilibrium in the past. Spatial analysis of molecular variance indicated no obvious phylogeographic structure.

scholarly journals Influence of environmental factors on the genetic variation of the aquatic macrophyte Ranunculus subrigidus on the Qinghai-Tibetan Plateau

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Zhigang Wu ◽  
Xinwei Xu ◽  
Juan Zhang ◽  
Gerhard Wiegleb ◽  
Hongwei Hou
Keyword(s):  
Genetic Diversity ◽  
Tibetan Plateau ◽  
Environmental Factors ◽  
Local Adaptation ◽  
Aquatic Macrophyte ◽  
Spatial Genetic Structure ◽  
Long Distance ◽  
Elevation Gradients ◽  
Mantel Tests ◽  
Genetic Patterns

Abstract Background Due to the environmental heterogeneity along elevation gradients, alpine ecosystems are ideal study objects for investigating how ecological variables shape the genetic patterns of natural species. The highest region in the world, the Qinghai-Tibetan Plateau, is a hotspot for the studies of evolutionary processes in plants. Many large rivers spring from the plateau, providing abundant habitats for aquatic and amphibious organisms. In the present study, we examined the genetic diversity of 13 Ranunculus subrigidus populations distributed throughout the plateau in order to elucidate the relative contribution of geographic distance and environmental dissimilarity to the spatial genetic pattern. Results A relatively low level of genetic diversity within populations was found. No spatial genetic structure was suggested by the analyses of molecular variance, Bayesian clustering analysis and Mantel tests. Partial Mantel tests and multiple matrix regression analysis showed a significant influence of the environment on the genetic divergence of the species. Both climatic and water quality variables contribute to the habitat heterogeneity of R. subrigidus populations. Conclusions Our results suggest that historical processes involving long-distance dispersal and local adaptation may account for the genetic patterns of R. subrigidus and current environmental factors play an important role in the genetic differentiation and local adaptation of aquatic plants in alpine landscapes.

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.

scholarly journals Intraspecific divergences and phylogeography of Panzerina lanata (Lamiaceae) in Northwest China

2018 ◽  
Author(s):  
Yanfen Zhao ◽  
Hongxiang Zhang ◽  
Borong Pan ◽  
Mingli Zhang
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Genetic ◽  
Divergence Time ◽  
Northwest China ◽  
Northwestern China ◽  
Intraspecific Diversity ◽  
Early Pleistocene ◽  
Helan Mountains ◽  
The Impact

Climactic fluctuations during the Quaternary played a crucial role in genetic diversity and population genetic structure of many plant species in northwestern China. In order to understand the impact of climate change on herbaceous plants, we studied Panzerina lanata (Lamiaceae), a widely distributed species. Two chloroplast DNA intergenic spacers (trnH-psbA and rpoB-trnC) were used to sequence 269 individuals from 27 populations and seven haplotypes were identified. Genetic structure and demographic characteristics were estimated using AMOVA, neutrality tests, and mismatch distribution analyses. The divergence times between the seven haplotypes were estimated using Beast. Our results revealed high levels of total genetic diversity (HT = 0.673±0.0869) and low levels of average within-population genetic diversity (HS = 0.033±0.0214). The analysis of molecular variance indicated major genetic differentiation among the three groups: northern, central, and eastern group. The species distribution modeling and demographic analysis indicated that P. lanata has not experience a recent range expansion. The divergence time within P. lanata occurred between the early Pleistocene and the late Pleistocene, which coincides with aridification and the expansion of the deserts in northwestern China that resulted in species diversification and habitat fragmentation. In addition, we speculate that the deserts and the Helan Mountains acted as effective geographic barriers that led to intraspecific diversity.

Staying close: short local dispersal distances on a managed forest of two Patagonian Nothofagus species

2020 ◽  
Vol 93 (5) ◽  
pp. 652-661 ◽  
Author(s):  
Georgina Sola ◽  
Verónica El Mujtar ◽  
Leonardo Gallo ◽  
Giovanni G Vendramin ◽  
Paula Marchelli
Keyword(s):  
Gene Flow ◽  
Genetic Structure ◽  
Spatial Genetic Structure ◽  
Pollen Dispersal ◽  
Dispersal Distance ◽  
Restricted Gene Flow ◽  
Fine Scale ◽  
Gene Dispersal ◽  
Mature Trees ◽  
The Impact

Abstract Understanding the impact of management on the dispersal potential of forest tree species is pivotal in the context of global change, given the implications of gene flow on species evolution. We aimed to determine the effect of logging on gene flow distances in two Nothofagus species from temperate Patagonian forests having high ecological relevance and wood quality. Therefore, a total of 778 individuals (mature trees and saplings) of Nothofagus alpina and N. obliqua, from a single plot managed 20 years ago (2.85 hectares), were mapped and genotyped at polymorphic nuclear microsatellite loci. Historical estimates of gene dispersal distance (based on fine-scale spatial genetic structure) and contemporary estimates of seed and pollen dispersal (based on spatially explicit mating models) were obtained. The results indicated restricted gene flow (gene distance ≤ 45 m, both pollen and seed), no selfing and significant seed and pollen immigration from trees located outside the studied plot but in the close surrounding area. The size of trees (diameter at breast height and height) was significantly associated with female and/or male fertility. The significant fine-scale spatial genetic structure was consistent with the restricted seed and pollen dispersal. Moreover, both estimates of gene dispersal (historical and contemporary) gave congruent results. This suggests that the recent history of logging within the study area has not significantly influenced on patterns of gene flow, which can be explained by the silviculture applied to the stand. The residual tree density maintained species composition, and the homogeneous spatial distribution of trees allowed the maintenance of gene dispersal. The short dispersal distance estimated for these two species has several implications both for understanding the evolution of the species and for defining management, conservation and restoration actions. Future replication of this study in other Nothofagus Patagonian forests would be helpful to validate our conclusions.

Sign in / Sign up

Export Citation Format

Share Document