Assessing Genetic Diversity of Canada Thistle (Cirsium arvense) in North America with Microsatellites

Invasive species such as Canada thistle pose a significant threat to ecosystems. The risk of introducing invasive species has increased with human activities, and the effects of such events have economic and aesthetic impacts. Native to Europe, Canada thistle is now established throughout temperate North America. Although there is documentation of early occurrences to North America, little is known on how it has become established in diverse habitats or how it continues to spread. We examined genetic diversity within and among nearly 1,700 Canada thistle individuals from 85 North American locations with the use of seven microsatellite markers in order to address these questions. PAUP and STRUCTURE programs were used to assess genetic diversity and relationships within and between populations. Populations exhibited greater within-population diversity (> 60%) than expected for a reported clonally reproducing species. Total diversity of sampled locations in North America (0.183) was less than previously reported for European locations (0.715), but the greater mean difference between North American populations (0.264 relative to 0.246 from England) suggests strong founder effects or restriction of gene flow influencing individual populations. Furthermore, analyses identified numerous instances where individuals from geographically distant regions clustered together, indicating long-distance translocation of propogules. However, isolation by distance analysis showed significant correlation between location and population genetic distances (r = 0.1917, P = 0.006). Within populations, nearly 92% of individuals sampled harbored unique multilocus genotypes, strongly suggesting that sexual reproduction is common. Within populations, analysis of genetic structure indicated significant admixture of genotypes throughout the invasive range in North America. The recurrent distribution of seed throughout North America has led to a highly diverse gene pool and increased the adaptive success Canada thistle to a wide variety of habitats. Future technologies developed for control of Canada thistle should consider this diversity.

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Phylogenetics of a Fungal Invasion: Origins and Widespread Dispersal of White-Nose Syndrome

mBio ◽

10.1128/mbio.01941-17 ◽

2017 ◽

Vol 8 (6) ◽

Cited By ~ 27

Author(s):

Kevin P. Drees ◽

Jeffrey M. Lorch ◽

Sebastien J. Puechmaille ◽

Katy L. Parise ◽

Gudrun Wibbelt ◽

...

Keyword(s):

Genetic Diversity ◽

North America ◽

North American ◽

Fungal Pathogen ◽

Phylogenetic Study ◽

Pseudogymnoascus Destructans ◽

Long Distance ◽

Recent Introduction ◽

White Nose Syndrome ◽

The North

ABSTRACT Globalization has facilitated the worldwide movement and introduction of pathogens, but epizoological reconstructions of these invasions are often hindered by limited sampling and insufficient genetic resolution among isolates. Pseudogymnoascus destructans , a fungal pathogen causing the epizootic of white-nose syndrome in North American bats, has exhibited few genetic polymorphisms in previous studies, presenting challenges for both epizoological tracking of the spread of this fungus and for determining its evolutionary history. We used single nucleotide polymorphisms (SNPs) from whole-genome sequencing and microsatellites to construct high-resolution phylogenies of P. destructans . Shallow genetic diversity and the lack of geographic structuring among North American isolates support a recent introduction followed by expansion via clonal reproduction across the epizootic zone. Moreover, the genetic relationships of isolates within North America suggest widespread mixing and long-distance movement of the fungus. Genetic diversity among isolates of P. destructans from Europe was substantially higher than in those from North America. However, genetic distance between the North American isolates and any given European isolate was similar to the distance between the individual European isolates. In contrast, the isolates we examined from Asia were highly divergent from both European and North American isolates. Although the definitive source for introduction of the North American population has not been conclusively identified, our data support the origin of the North American invasion by P. destructans from Europe rather than Asia. IMPORTANCE This phylogenetic study of the bat white-nose syndrome agent, P. destructans , uses genomics to elucidate evolutionary relationships among populations of the fungal pathogen to understand the epizoology of this biological invasion. We analyze hypervariable and abundant genetic characters (microsatellites and genomic SNPs, respectively) to reveal previously uncharacterized diversity among populations of the pathogen from North America and Eurasia. We present new evidence supporting recent introduction of the fungus to North America from a diverse Eurasian population, with limited increase in genetic variation in North America since that introduction.

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Geographic patterns of genetic diversity in North American trees: a continent-wide analysis

Canadian Journal of Forest Research ◽

10.1139/cjfr-2020-0539 ◽

2021 ◽

Author(s):

Andrew V. Gougherty

Keyword(s):

Genetic Diversity ◽

Population Genetics ◽

North America ◽

North American ◽

Tree Species ◽

Geographic Patterns ◽

Study Characteristics ◽

Dispersal Traits ◽

The Last Glacial Maximum ◽

The Last Glacial

In the northern hemisphere, many species have been reported to have greater genetic diversity in southern populations than northern populations - ostensibly due to migration northward following the last glacial maximum (LGM). The generality of this pattern, while well-established for some taxa, remains unclear for North American trees. To address this issue, I collected published population genetics data for 73 North American tree species, and tested whether genetic diversity was associated with latitude or longitude and whether geographic trends were associated with dispersal traits, range or study characteristics. I found there were no general geographic patterns in genetic diversity, and the strength of the geographic gradients were not associated with any species or study characteristics. Species in the northern and western regions of North America tended to have more species with genetic diversity that declined with latitude, but most species had no significant trend. This work shows that North American trees have complex, individualistic, patterns of genetic diversity that may negate explanation by any particular dispersal trait or range characteristic.

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Knotweed Management Strategies in North America with the Advent of Widespread Hybrid Bohemian Knotweed, Regional Differences, and the Potential for Biocontrol Via the Psyllid Aphalara itadori Shinji

Invasive Plant Science and Management ◽

10.1614/ipsm-d-15-00047.1 ◽

2016 ◽

Vol 9 (1) ◽

pp. 60-70 ◽

Cited By ~ 10

Author(s):

David R. Clements ◽

Todd Larsen ◽

Jennifer Grenz

Keyword(s):

Biological Control ◽

Invasive Species ◽

Genetic Variation ◽

North America ◽

North American ◽

Regional Differences ◽

The United States ◽

The North ◽

Variable Nature ◽

Available Resources

AbstractInvasive species with distributions that encompass much of the North American environment often demand a range of management approaches, for several key reasons. Firstly, the North American environment includes a large number of highly variable habitats in terms of climatic, edaphic, and landscape features. Secondly, these regional habitat differences are accentuated by jurisdictions within Canada and the United States, whereby approaches and available resources differ at local, regional, and national scales. Another important consideration is whether an invasive species or complex also possesses genetic variation. All three of these factors render the knotweed complex in North America a highly variable target for management. In this paper we review existing knowledge of the variable nature of knotweed species (Fallopia japonica (Houtt.) Ronse Decr., Fallopia sachalinensis (F. Schmidt ex Maxim) Ronse Decr., and Fallopia × bohemica, (Chrtek and Chrtková) J. P. Bailey in North America, and evaluate how herbicidal, mechanical and biological control measures must account for this genetic variation, as well as accounting for regional differences and the potential northward expansion of knotweed under climate change. The imminent release of the psyllid, Aphalara itadori Shinji as a biological control agent in North America must also navigate regional and genetic differences. Prior European experience dealing with the three knotweed species should prove useful, but additional research is needed to meet the emerging challenge posed by F. × bohemica in North America, including the possibility of glyphosate resistance. Managers also face challenges associated with posttreatment restoration measures. Furthermore, disparities in resources available to address knotweed management across the continent need to be addressed to contain the rapid spread of this highly persistent and adaptable species. Linking practitioners dealing with knotweed “on the ground” with academic research is a crucial step in the process of marshalling all available resources to reduce the rapidly spreading populations of knotweed.

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

Sustainability ◽

10.3390/su11205863 ◽

2019 ◽

Vol 11 (20) ◽

pp. 5863 ◽

Cited By ~ 2

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.

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Serial founder effects and genetic differentiation during worldwide range expansion of monarch butterflies

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.2230 ◽

2014 ◽

Vol 281 (1797) ◽

pp. 20142230 ◽

Cited By ~ 44

Author(s):

Amanda A. Pierce ◽

Myron P. Zalucki ◽

Marie Bangura ◽

Milan Udawatta ◽

Marcus R. Kronforst ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Differentiation ◽

Genetic Drift ◽

North American ◽

Range Expansion ◽

Dispersal Ability ◽

Founder Effects ◽

Long Distance ◽

Mobile Species ◽

High Dispersal

Range expansions can result in founder effects, increasing genetic differentiation between expanding populations and reducing genetic diversity along the expansion front. However, few studies have addressed these effects in long-distance migratory species, for which high dispersal ability might counter the effects of genetic drift. Monarchs ( Danaus plexippus ) are best known for undertaking a long-distance annual migration in North America, but have also dispersed around the world to form populations that do not migrate or travel only short distances. Here, we used microsatellite markers to assess genetic differentiation among 18 monarch populations and to determine worldwide colonization routes. Our results indicate that North American monarch populations connected by land show limited differentiation, probably because of the monarch's ability to migrate long distances. Conversely, we found high genetic differentiation between populations separated by large bodies of water. Moreover, we show evidence for serial founder effects across the Pacific, suggesting stepwise dispersal from a North American origin. These findings demonstrate that genetic drift played a major role in shaping allele frequencies and created genetic differentiation among newly formed populations. Thus, range expansion can give rise to genetic differentiation and declines in genetic diversity, even in highly mobile species.

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Genetic diversity of the lichen-forming alga, Diplosphaera chodatii, in North America and Europe

The Lichenologist ◽

10.1017/s0024282913000510 ◽

2013 ◽

Vol 45 (6) ◽

pp. 799-813 ◽

Cited By ~ 7

Author(s):

Kyle M. FONTAINE ◽

Elfie STOCKER-WÖRGÖTTER ◽

Tom BOOTH ◽

Michele D. PIERCEY-NORMORE

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Gene Flow ◽

North America ◽

Isolation By Distance ◽

Water Level Fluctuations ◽

Free Living ◽

Climatic Zones ◽

Algal Symbiont ◽

Low Levels

AbstractDermatocarpon luridum is a subaquatic lichen which is distributed within temperate climatic zones around the world. It colonizes rock substrata along the shoreline of lakes and rivers of watersheds that regularly experience water level fluctuations. The mycobiont produces perithecia with small, simple spores that are thought to be wind dispersed. The photobiont, Diplosphaera chodatii, occurs both free-living and lichenized but little is known about its distribution and dispersal. The goal of this study was to compare the population structure of the photobiont from lakes and rivers in central North America with those of Europe. Specimens were collected in Manitoba, Canada and Austria. Population structure of the algal symbiont was assessed using the internal transcribed spacer (ITS) of ribosomal DNA (rDNA) and actin gene sequences. Results showed that genetic diversity and gene flow was high within local populations, but gene flow was low between continental populations. Low levels of gene flow between the most distant populations support the isolation-by-distance theory. The photobiont on both continents is also reported to be the photobiont for other lichen species contributing to photobiont availability for D. luridum.

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Economic costs of biological invasions within North America

NeoBiota ◽

10.3897/neobiota.67.58038 ◽

2021 ◽

Vol 67 ◽

pp. 485-510

Author(s):

Robert Crystal-Ornelas ◽

Emma J. Hudgins ◽

Ross N. Cuthbert ◽

Phillip J. Haubrock ◽

Jean Fantle-Lepczyk ◽

...

Keyword(s):

Invasive Species ◽

North America ◽

North American ◽

Research Effort ◽

The United States ◽

Greater Antilles ◽

Economic Costs ◽

The North ◽

Species Invasions ◽

American Economy

Invasive species can have severe impacts on ecosystems, economies, and human health. Though the economic impacts of invasions provide important foundations for management and policy, up-to-date syntheses of these impacts are lacking. To produce the most comprehensive estimate of invasive species costs within North America (including the Greater Antilles) to date, we synthesized economic impact data from the recently published InvaCost database. Here, we report that invasions have cost the North American economy at least US$ 1.26 trillion between 1960 and 2017. Economic costs have climbed over recent decades, averaging US$ 2 billion per year in the early 1960s to over US$ 26 billion per year in the 2010s. Of the countries within North America, the United States (US) had the highest recorded costs, even after controlling for research effort within each country ($5.81 billion per cost source in the US). Of the taxa and habitats that could be classified in our database, invasive vertebrates were associated with the greatest costs, with terrestrial habitats incurring the highest monetary impacts. In particular, invasive species cumulatively (from 1960–2017) cost the agriculture and forestry sectors US$ 527.07 billion and US$ 34.93 billion, respectively. Reporting issues (e.g., data quality or taxonomic granularity) prevented us from synthesizing data from all available studies. Furthermore, very few of the known invasive species in North America had reported economic costs. Therefore, while the costs to the North American economy are massive, our US$ 1.26 trillion estimate is likely very conservative. Accordingly, expanded and more rigorous economic cost reports are necessary to provide more comprehensive invasion impact estimates, and then support data-based management decisions and actions towards species invasions.

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Broad geographic sampling and DNA barcoding do not support the presence of Helobdella stagnalis (Linnaeus, 1758) (Clitellata: Glossiphoniidae) in North America

Zootaxa ◽

10.11646/zootaxa.4671.1.1 ◽

2019 ◽

Vol 4671 (1) ◽

pp. 1-25 ◽

Cited By ~ 1

Author(s):

RAFAEL EIJI IWAMA ◽

ALEJANDRO OCEGUERA-FIGUEROA ◽

DANIELLE DE CARLE ◽

CLAIRE MANGLICMOT ◽

CHRISTER ERSÉUS ◽

...

Keyword(s):

North America ◽

North American ◽

Dorsal Surface ◽

Genetic Distances ◽

The Body ◽

Recent Analysis ◽

Intraspecific Divergence ◽

Geographic Boundaries ◽

The Usa ◽

Taxonomic Confusion

The description of Helobdella stagnalis (Linnaeus, 1758) has emphasized the presence of a nuchal, chitinous scute located on the dorsal surface in the first third of the body as the diagnostic character for the species. Historically, identifications of species of Helobdella have relied heavily on this character and, as a result, Helobdella stagnalis has been reported from an inordinately broad geographic range, including Europe, Asia, Africa, North America, and South America. In addition to a few earlier investigations, a recent analysis showed that great genetic distances (orders of magnitude greater than previous estimations of intraspecific divergence in leeches) are present between scute-bearing specimens identified as H. stagnalis from Europe and North America, implying that H. stagnalis does not occur in North America. The present study expands the geographic boundaries of taxon sampling for both European and North American taxa, and re-examines the phylogenetic relationships and cytochrome c oxidase subunit I (COI) variation within scute-bearing species of the genus Helobdella. Our analyses include specimens putatively identified as “Helobdella stagnalis” from Sweden, Norway, Iceland, England, France, Italy, Slovenia, Turkey, Russia, and Iran, as well as numerous localities covering Canada and the USA. Our results corroborate previous studies in that European and west Asian specimens form a clade, including the neotype, which is separate from North American taxa. To alleviate future taxonomic confusion, we redescribe H. stagnalis and designate a neotype from the inferred type locality. The designation of a neotype stabilizes the taxonomy of scute-bearing leeches of the genus Helobdella and enables us to definitively correct erroneous identifications reported in previous studies. We also note that at least four lineages of scute-bearing, North American species of Helobdella lack formal descriptions.

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Molecular systematics reveals multiple lineages and cryptic speciation in the freshwater crayfish Parastacus brasiliensis (von Martens, 1869) (Crustacea : Decapoda : Parastacidae)

Invertebrate Systematics ◽

10.1071/is18012 ◽

2018 ◽

Vol 32 (6) ◽

pp. 1265 ◽

Cited By ~ 1

Author(s):

Ivana Miranda ◽

Kelly M. Gomes ◽

Felipe B. Ribeiro ◽

Paula B. Araujo ◽

Catherine Souty-Grosset ◽

...

Keyword(s):

Genetic Diversity ◽

Isolation By Distance ◽

Conservation Status ◽

Sensu Stricto ◽

Genetic Distances ◽

Distribution Data ◽

Lake Basin ◽

Gene Pools ◽

Freshwater Crayfish ◽

Isolated Populations

The characterisation of intraspecific genetic diversity in representatives of the South American crayfish genus Parastacus Huxley, 1879 is here carried out for the first time by comparing populations of Parastacus brasiliensis (von Martens, 1869) as currently defined. Phylogenetic reconstructions based on mitochondrial and nuclear markers indicate the existence of multiple lineages, of which only one can be considered as P. brasiliensis sensu stricto. In addition, there are seven other lineages, one of which is the subspecies Parastacus brasiliensis promatensis Fontoura & Conter, 2008, which is here elevated to species level. We thereby increase to 14 the number of recognised species within Parastacus in South America. Genetic distances among P. brasiliensis sensu stricto and the lineages ‘A’, ‘B’ and ‘C’ increase with geographical distances, suggesting isolation by distance as an important driver of diversification, and eventually speciation, in these burrowing crayfishes. Parastacus brasiliensis occurs mainly in the Guaíba Lake basin and studied populations show limited connectivity and gene flow, probably due to habitat fragmentation. On the basis of genetic and distribution data, the conservation status of P. brasiliensis sensu stricto is confirmed as Near Threatened (NT). These findings lead us to encourage the establishment of preservation areas for isolated populations. The importance of preserving the newly recognised distinct gene pools in order to maintain overall genetic diversity is emphasised.

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