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Euphrasia samples used in this study. (A) Tetraploid British Euphrasia (here E. arctica) have glabrous leaves sometimes with sparse short eglandular hairs or bristles. (B) Diploid British Euphrasia have long glandular hairs. (C) Collection sites of Euphrasia DNA samples. Diploids are shown in red, tetraploids in blue. Orange boxes correspond to the three broad sampling areas. Photo credits: Alex Twyford, Max Brown.
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DNA barcoding is emerging as a useful tool not only for species identification but for studying evolutionary and ecological processes. Although plant DNA barcodes do not always provide species-level resolution, the generation of large DNA barcode datasets can provide insights into the mechanisms underlying the generation of species diversity. Here,...
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Context 1
... 19 currently recognized British Euphrasia species are all annual, selfing or mixed-mating small herbaceous plants, which occur in a range of habitats including coastal turf, chalk downland, mountain ridges and hea- ther moorland (French et al. 2004). The species can be divided into two groups, glabrous or short eglandular hairy tetraploids (15 species, Fig. 1A), or long glandular hairy diploids (4 species, Fig. 1B). Our sampling includes representatives of all British species ( Fig. 1C; Supporting Information- Table S1). Samples were collected in South West England and Wales to allow us to include mixed populations of diploids and tetraploids, early generation diploid × tetraploid hybrids, and two diploid hybrid spe- cies hypothesized to be derived from diploid × tetraploid crosses (E. vigursii, parentage: E. rostkoviana × E. micran- tha; E. rivularis, parentage: E. anglica × E. micrantha; Yeo 1956). Samples from Scotland allows us to sample com- plex tetraploid taxa and tetraploid hybrids, plus scarcer Scottish diploids. Our sampling scheme investigated range-wide variation by targeting many taxa and popula- tions, with a focus on collecting multiple species in areas of sympatry. We chose not to include detailed intrapopu- lation sampling because prior work has shown low intra- population diversity, with populations frequently fixed for a given allele (French et al. 2008). All samples collected prior to 2012 were identified by former Euphrasia referee Alan Silverside, while recent samples were identified by current referee Chris ...
Context 2
... 19 currently recognized British Euphrasia species are all annual, selfing or mixed-mating small herbaceous plants, which occur in a range of habitats including coastal turf, chalk downland, mountain ridges and hea- ther moorland (French et al. 2004). The species can be divided into two groups, glabrous or short eglandular hairy tetraploids (15 species, Fig. 1A), or long glandular hairy diploids (4 species, Fig. 1B). Our sampling includes representatives of all British species ( Fig. 1C; Supporting Information- Table S1). Samples were collected in South West England and Wales to allow us to include mixed populations of diploids and tetraploids, early generation diploid × tetraploid hybrids, and two diploid hybrid spe- cies hypothesized to be derived from diploid × tetraploid crosses (E. vigursii, parentage: E. rostkoviana × E. micran- tha; E. rivularis, parentage: E. anglica × E. micrantha; Yeo 1956). Samples from Scotland allows us to sample com- plex tetraploid taxa and tetraploid hybrids, plus scarcer Scottish diploids. Our sampling scheme investigated range-wide variation by targeting many taxa and popula- tions, with a focus on collecting multiple species in areas of sympatry. We chose not to include detailed intrapopu- lation sampling because prior work has shown low intra- population diversity, with populations frequently fixed for a given allele (French et al. 2008). All samples collected prior to 2012 were identified by former Euphrasia referee Alan Silverside, while recent samples were identified by current referee Chris ...
Context 3
... 19 currently recognized British Euphrasia species are all annual, selfing or mixed-mating small herbaceous plants, which occur in a range of habitats including coastal turf, chalk downland, mountain ridges and hea- ther moorland (French et al. 2004). The species can be divided into two groups, glabrous or short eglandular hairy tetraploids (15 species, Fig. 1A), or long glandular hairy diploids (4 species, Fig. 1B). Our sampling includes representatives of all British species ( Fig. 1C; Supporting Information- Table S1). Samples were collected in South West England and Wales to allow us to include mixed populations of diploids and tetraploids, early generation diploid × tetraploid hybrids, and two diploid hybrid spe- cies hypothesized to be derived from diploid × tetraploid crosses (E. vigursii, parentage: E. rostkoviana × E. micran- tha; E. rivularis, parentage: E. anglica × E. micrantha; Yeo 1956). Samples from Scotland allows us to sample com- plex tetraploid taxa and tetraploid hybrids, plus scarcer Scottish diploids. Our sampling scheme investigated range-wide variation by targeting many taxa and popula- tions, with a focus on collecting multiple species in areas of sympatry. We chose not to include detailed intrapopu- lation sampling because prior work has shown low intra- population diversity, with populations frequently fixed for a given allele (French et al. 2008). All samples collected prior to 2012 were identified by former Euphrasia referee Alan Silverside, while recent samples were identified by current referee Chris ...
Context 4
... ITS2 data revealed strong partitioning by ploidy. Of the 23 alleles, three (H1, H20 and H21) were restricted to diploids, and 19 to tetraploids, with only one allele (H2) shared across ploidy levels (Table 1). H2 was not only shared across ploidy levels but was also the most wide- spread variant, found in 67 samples across 34 popula- tions. This included geographically distinct species such as the Scottish endemic E. marshallii and the predomi- nantly English and Welsh E. anglica, and ecologically contrasting taxa such as the dry heathland specialist E. micrantha and the (currently unpublished) obligate coastal 'E. fharaidensis'. Overall, 86 % of taxa had one of six widespread alleles. There were also a large num- ber of rare variants, with over two-thirds restricted to a single population (17 alleles: H4, H7-H10, H12-H21 and H23; Table 1). The remaining alleles found in multiple populations (H1, H2, H3, H5, H6, H11) showed no clear pattern of geography, with three found in all geographic regions (England, Scotland, Wales) and the remaining three shared between two geographic regions. Similarly, patterns of shared sequence variation do not follow species boundaries. Of the eight species with multiple populations (excluding hybrids), none of them had a diagnostic ITS2 sequence. Despite variants being shared across taxa, there was no evidence for this being due to non-neutral processes, as the value of Tajima's D (−0.17) was not significantly different from ...
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Citations
... It also has similarities with the jewel orchids in Vietnam, where multi-locus barcodes cannot improve resolution for species classification (Ho et al. 2021). The results of DNA barcoding in the genera level, infrageneric rank, and species level may have a different result, such as in Euphrasia where ITS barcoding cannot provide a clear resolution of species-level separation (Wang et al. 2018). In some arid plant, rbcL (88%) have a higher success amplification rate than matK as a barcode (Bafeel et al. 2011). ...
In silico biology is considered as an effective and applicable approach to initiate various research, such as biodiversity taxonomical conservation. Phylogenetic analysis using in silico taxonomy method for orchid species can provide data on genetic diversity and evolutionary relationships. One particular method that can be used to evaluate specific targets of gene loci in the taxonomic study is DNA barcoding. This research was conducted to determine the specific target locus gene using matK, rbcL, rpoC1, and nrDNA markers for DNA barcoding of the Coelogyne genus with in silico approach using phylogenetic analysis. All marker sequences were collected from the NCBI website and analysed using several softwares and methods, namely Clustal X for sample sequence alignment and MEGA 11 for phylogenetic tree construction and analysis. The results showed that the gene locus in Coelogyne recommended was the nrDNA gene locus. Phylogenetic analysis revealed that the use of the nrDNA gene locus was able to separate 17 Coelogyne species with two outgroup species, namely Cymbidium and Vanilla, then followed with ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) while the other gene loci, namely maturase K (matK) and polymerase beta' subunit (rpoC1) provided a visual phy-logenetic tree in which the two outgroup species entered into the same clade as the Coelogyne species. Thus, the results of this study can be used as a reference to support the Coelogyne breeding and conservation program.
... Nickrent, personal communication). There are 21 Euphrasia species in Britain and Ireland, representing a taxonomically complex group characterized by recent postglacial divergence (Wang et al., 2018), phenotypic plasticity , and rampant hybridization (Metherell and Rumsey, 2018). British and Irish Euphrasia, all annuals, consist of five predominantly outcrossing diploid species and 16 selfing or mixed-mating tetraploid species (French et al., 2005). ...
... Both of these species are widespread and are reported to hybridize locally at a number of sites across Britain, based on morphological observations (Stace et al., 2015). We first used Sanger sequencing of a locus that shows diagnostic differences between diploid and tetraploid species (Wang et al., 2018) to see if there is any clear evidence of hybridization. We then used genotyping by sequencing (GBS) to generate single-nucleotide polymorphism (SNP) markers and test for evidence of potentially cryptic introgression. ...
... We sequenced 70 Euphrasia individuals for part of the internal transcribed spacer of nuclear ribosomal DNA (ITS) as this locus demonstrates diagnostic differences between diploid and tetraploid species (Wang et al., 2018). We also performed a preliminary survey of plastid variation by sequencing the variable trnL spacer region (rpL32-trnL UAG ) in a test panel of four diploid and four tetraploid individuals. ...
Premise of the study:
Strong postzygotic reproductive isolating barriers are usually expected to limit the extent of natural hybridisation between species with contrasting ploidy. However, genomic sequencing has revealed previously overlooked examples of natural cross-ploidy hybridisation in different flowering plant genera, suggesting this phenomenon may be more common than once thought. Here, we investigate potential cross-ploidy hybridisation in British eyebrights (Euphrasia, Orobanchaceae), a group where thirteen putative cross-ploidy hybrid combinations have been reported based on morphology.
Methods:
We analysed a contact zone between diploid E. rostkoviana and tetraploid E. arctica in Wales. We sequenced part of the internal transcribed spacer (ITS) of nuclear ribosomal DNA and used Genotyping by Sequencing (GBS) to look for evidence of cross-ploidy hybridisation and introgression.
Key results:
Common variant sites in the ITS region were fixed between diploids and tetraploids, indicating a strong barrier to hybridisation. Clustering analyses of 356 SNPs generated using GBS clearly separated samples by ploidy and revealed strong genetic structure (FST = 0.44). However, the FST distribution across all SNPs was bimodal, indicating potential differential selection on loci between diploids and tetraploids. Demographic inference with δaδI suggested potential gene flow - with this limited to around one or fewer migrants per generation.
Conclusions:
Our results suggest recent cross-ploidy hybridisation is rare or absent in a site of secondary contact in Euphrasia. While a strong ploidy barrier prevents hybridisation over ecological time-scales, such hybrids may form in stable populations over evolutionary time-scales and potentially allow for cross-ploidy introgression to take place. This article is protected by copyright. All rights reserved.
... previously uncovered considerable intraspecific genome size variation (Becher et al., 2021). These diploids form a complex of hybridising taxa, which are not distinguishable by DNA barcoding (Wang et al., 2018) albeit there is some congruence between morphology and patterns of variation of amplifiedfragment length polymorphisms (French et al., 2008). We intentionally avoid using assembly-based approaches, which we have previously used to investigate species differences (Becher et al., 2020). ...
... British Euphrasia have become known for their taxonomic complexity (sensu Ennos et al., 2005). While the diploids are largely morphologically distinct from one another (although numerous diploid hybrid combinations are known), they cannot be distinguished reliably by ITS or plastid barcoding (Wang et al., 2018), raising the question whether they are genetically distinct. Adding to this doubt, we have also recently uncovered considerable intra-and interspecific genome size variation within ploidy levels and showed that 'population' is a far better predictor of an individual's genome size than 'species' (Becher et al., 2021). ...
Genome size variation within plant taxa is due to presence/absence variation, which may affect low-copy sequences or genomic repeats of various frequency classes. However, identifying the sequences underpinning genome size variation is challenging because genome assemblies commonly contain collapsed representations of repetitive sequences and because genome skimming studies by design miss low-copy number sequences. Here, we take a novel approach based on k-mers, short sub-sequences of equal length k, generated from whole-genome sequencing data of diploid eyebrights (Euphrasia), a group of plants that have considerable genome size variation within a ploidy level. We compare k-mer inventories within and between closely related species, and quantify the contribution of different copy number classes to genome size differences. We further match high-copy number k-mers to specific repeat types as retrieved from the RepeatExplorer2 pipeline. We find genome size differences of up to 230Mbp, equivalent to more than 20% genome size variation. The largest contributions to these differences come from rDNA sequences, a 145-nt genomic satellite and a repeat associated with an Angela transposable element. We also find size differences in the low-copy number class (copy number ≤ 10×) of up to 27 Mbp, possibly indicating differences in gene space between our samples. We demonstrate that it is possible to pinpoint the sequences causing genome size variation within species without the use of a reference genome. Such sequences can serve as targets for future cytogenetic studies. We also show that studies of genome size variation should go beyond repeats if they aim to characterise the full range of genomic variants. To allow future work with other taxonomic groups, we share our k-mer analysis pipeline, which is straightforward to run, relying largely on standard GNU command line tools.
... We noticed the same phenomenon in certain species, and the trnL gene was extended along the SSC/IRb border in certain species, which could be attributed to the extension in the IR region. The ycf1 gene present at the SSC/IRb borders of angiosperm plastomes is often pseudogenized, and the expansion length of ycf1 could influence the IR length and the gene distribution at the SC/IR borders [52][53][54]. ...
The Plicosepalus genus includes hemiparasitic mistletoe and belongs to the Loranthaceae family, and it has several medicinal uses. In the present study, we sequenced the complete plastomes of two species, Plicosepalus acaciae and Plicosepalus curviflorus, and compared them with the plastomes of photosynthetic species (hemiparasites) and nonphotosynthetic species (holoparasites) in the order Santalales. The complete chloroplast genomes of P. acaciae and P. curviflorus are circular molecules with lengths of 120,181 bp and 121,086 bp, respectively, containing 106 and 108 genes and 63 protein-coding genes, including 25 tRNA and 4 rRNA genes for each species. We observed a reduction in the genome size of P. acaciae and P. curviflorus and the loss of certain genes, although this reduction was less than that in the hemiparasite and holoparasitic cp genomes of the Santalales order. Phylogenetic analysis supported the taxonomic state of P. acaciae and P. curviflorus as members of the family Loranthaceae and tribe Lorantheae; however, the taxonomic status of certain tribes of Loranthaceae must be reconsidered and the species that belong to it must be verified. Furthermore, available chloroplast genome data of parasitic plants could help to strengthen efforts in weed management and encourage biotechnology research to improve host resistance.
... The genus is perhaps most renowned for its taxonomic complexity, particularly in Europe (French et al., 2008). The postglacial radiation in northern Europe includes numerous closely related taxa that are extremely challenging to separate based on morphology (Yeo, 1978) or with DNA barcoding (Wang et al., 2018). The small stature of these plants (frequently <10 cm tall) and their phenotypic plasticity (Karlsson, 1984;Zopfi, 1997;Brown et al., 2020), coupled with many traits demonstrating population-level rather than species-level differences due to limited gene flow as a consequence of their selfing or partly selfing mating system , all further confound species identification. ...
... First, we study the enigmatic relationships of postglacial northern European Euphrasia species, particularly those present in Britain. We build on a number of previous genetic studies (French et al., 2008;Gussarova et al., 2008;Wang et al., 2018;Becher et al., 2020), generating new sequence data and re-analyzing previous sequences. This microevolutionary focus, aimed at using dense species sampling and the use of multiple individuals per species, allows us to Frontiers in Plant Science | www.frontiersin.org ...
... Phylogenetic discordance has been observed in numerous plant studies and is increasingly considered the norm (Rose et al., 2021). Here, we confirm that signals of phylogenetic discordance observed with Sanger sequencing of few loci at the regional (Wang et al., 2018), and the global scale (Gussarova et al., 2008), are indeed detected with genomic data. The lack of clear geographic, taxonomic or ploidy-related structuring in the plastid genome phylogeny, coupled with incongruence to the well-supported nuclear genomic phylogeny, shows the plastid does not track other loci and variation is shaped by other evolutionary forces. ...
Disentangling the phylogenetic relationships of taxonomically complex plant groups is often mired by challenges associated with recent speciation, hybridization, complex mating systems, and polyploidy. Here, we perform a phylogenomic analysis of eyebrights (Euphrasia), a group renowned for taxonomic complexity, with the aim of documenting the extent of phylogenetic discordance at both deep and at shallow phylogenetic scales. We generate whole-genome sequencing data and integrate this with prior genomic data to perform a comprehensive analysis of nuclear genomic, nuclear ribosomal (nrDNA), and complete plastid genomes from 57 individuals representing 36 Euphrasia species. The species tree analysis of 3,454 conserved nuclear scaffolds (46 Mb) reveals that at shallow phylogenetic scales postglacial colonization of North Western Europe occurred in multiple waves from discrete source populations, with most species not being monophyletic, and instead combining genomic variants from across clades. At a deeper phylogenetic scale, the Euphrasia phylogeny is structured by geography and ploidy, and partially by taxonomy. Comparative analyses show Southern Hemisphere tetraploids include a distinct subgenome indicative of independent polyploidy events from Northern Hemisphere taxa. In contrast to the nuclear genome analyses, the plastid genome phylogeny reveals limited geographic structure, while the nrDNA phylogeny is informative of some geographic and taxonomic affinities but more thorough phylogenetic inference is impeded by the retention of ancestral polymorphisms in the polyploids. Overall our results reveal extensive phylogenetic discordance at both deeper and shallower nodes, with broad-scale geographic structure of genomic variation but a lack of definitive taxonomic signal. This suggests that Euphrasia species either have polytopic origins or are maintained by narrow genomic regions in the face of extensive homogenizing gene flow. Moreover, these results suggest genome skimming will not be an effective extended barcode to identify species in groups such as Euphrasia, or many other postglacial species groups.
... Three plastid regions (rbcL, matK and trnH-psbA) plus the nuclear ribosomal DNA internal transcribed spacer region ITS, or their combination, are widely used as standard barcodes for plants (CBOL Plant Working Group, 2009;China Plant BOL Group, 2011). However, for complex and closely related taxa, these regions often lack adequate variation Wang et al., 2018), resulting in low species discrimination rates. To overcome this problem, more variable sequence regions may be used to supplement the standard plant barcodes and provide more informative characters to help distinguish taxa. ...
The aim of DNA barcoding is to enable fast and accurate species identification. However, universal plant DNA barcodes often do not provide species-level discrimination, especially in taxonomically complex groups. Here we use Lauraceae for the design and evaluation of DNA barcoding strategies, considering: (1) the efficacy of taxon-specific DNA barcode regions compared with universal barcodes for species discrimination; and (2) how the extent of intra-and interspecific sampling affects species discrimination rates. To address these areas, we targeted the highly polymorphic, taxon-specific barcode regions ycf1 + ndhH-rps15 + trnL-ycf2 for Lauraceae and compared them against the suite of standard plastid loci used for DNA barcoding (rbcL + matK + trnH-psbA) and the standard nuclear barcode ITS. The highest discrimination success came from nrDNA ITS, whereas the plastid regions (rbcL + matK + trnH-psbA) and the taxon-specific regions (ycf1 + ndhH-rps15 + trnL-ycf2) showed limited and inconsistent resolution. These results highlight that taxon-specific plastid barcodes may provide limited gains in discriminatory power in complex, closely related groups like Lauraceae. Moreover, our study showed that species discrimination greatly depends on the taxon sampling scheme, with relatively lower species discrimination observed where there is more comprehensive intra-and interspecific sampling. The outstanding challenge for plant DNA barcoding is the development of assays that allow routine low-cost access to large numbers of nuclear markers to facilitate the sequencing of large numbers of individuals. ADDITIONAL KEYWORDS: DNA barcoding-ITS-phylogenetics-plastid DNA-specific barcode design.
... British Euphrasia have become known for their taxonomic complexity. While the diploids are largely 533 morphologically distinct from one another (although numerous diploid hybrid combinations are 534 known), they cannot be distinguished reliably by ITS or plastid barcoding(Wang et al., 2018), 535 raising the question whether they are genetically distinct. Adding to this doubt, we have also recently 536 uncovered considerable intra and interspecific genome size variation within Euphrasia ploidy levels 537and showed that 'population' is a far better predictor of an individual's genome size than 'species' 538 (Becher et al., 2021). ...
Genome size variation within plant (and other) taxa may be due to presence/absence variation in low-copy sequences or copy number variation in genomic repeats of various frequency classes. However, identifying the sequences underpinning genome size variation has been challenging because genome assemblies commonly contain collapsed representations of repetitive sequences and because genome skimming studies miss low-copy number sequences.
Here, we take a novel approach based on k-mers, short sub-sequences of equal length k , generated from whole genome sequencing data of diploid eyebrights ( Euphrasia ), a group of plants which have considerable genome size variation within a ploidy level. We compare k-mer inventories within and between closely related species, and quantify the contribution of different copy number classes to genome size differences. We further assign high-copy number k-mers to specific repeat types as retrieved from the RepeatExplorer2 pipeline.
We find complex patterns of k-mer differences between samples. While all copy number classes contributed to genome size variation, the largest contribution came from repeats with 1000-10,000 genomic copies including the 45S rDNA satellite DNA and, unexpectedly, a repeat associated with an Angela transposable element. We also find size differences in the low-copy number class, likely indicating differences in gene space between our samples.
In this study, we demonstrate that it is possible to pinpoint the sequences causing genome size variation within species without use of a reference genome. Such sequences can serve as targets for future cytogenetic studies. We also show that studies of genome size variation should go beyond repeats and consider the whole genome. To allow future work with other taxonomic groups, we share our analysis pipeline, which is straightforward to run, relying largely on standard GNU command line tools.
... Overall, the hosts that emerged as most consistently advantageous across all four Euphrasia species were Lolium perenne and Lotus corniculatus, which fulfil many of the earlier criteria (Beddows, 1967;Jones & Turkington, 1986). These conserved parasite responses are notable as we used highly divergent diploid and tetraploid Euphrasia species (c. 5% nucleotide divergence, corresponding to c. 8 Myr divergence (Wang et al., 2018;Becher et al., 2020)). In contrast, host conservation in many highly specialized holoparasitic taxa, like Orobanche, is uncommon, with host specific ecotypes found even within the same parasite species (Thorogood et al., 2009). ...
Generalist hemiparasites may attach to many different host species and experience complex parasite–host interactions. How these parasite–host interactions impact on the fitness of hemiparasitic plants remain largely unknown.
We used experimentally tractable eyebrights (Euphrasia, Orobanchaceae) to understand parasite–host species interactions affecting the performance of a generalist hemiparasitic plant. Common garden experiments were carried out measuring Euphrasia performance across 45 diverse hosts and in different parasite–host combinations.
We show that variation in hemiparasite performance can be attributed mainly to host species and host phylogenetic relationships (λ = 0.82; 0.17–1.00 CI). When variation in performance is considered temporally, annual host species cause earlier flowering, and lead to poorer performance late in the season. While Euphrasia species typically perform similarly on a given host species, some eyebrights show more specialized parasite–host species interactions.
Our results show that generalist hemiparasites only benefit from attaching to a limited, but phylogenetically divergent, subset of hosts. The conserved responses of divergent Euphrasia species suggest hemiparasite performance is affected by common host attributes. However, evidence for more complex parasite–host species interactions show that a generalist hemiparasite can potentially respond to individual host selection pressures and may adapt to local host communities.
... at British tetraploids are closely related allotetraploids, with one sub-genome derived from, or closely related to, British diploids (Becher et al., 2020). The genus is an ideal group for investigating genome size variation within and between closely related species because species diversification is frequently postglacial (Gussarova et al., 2008;X. Wang et al., 2018), with many taxa being narrow endemics or recent hybrid species. ...
Background and aims:
Genome size varies considerably across the diversity of plant life. Although genome size is, by definition, affected by genetic presence/absence variants, which are ubiquitous in population sequencing studies, genome size is often treated as an intrinsic property of a species. Here, we studied intra- and interspecific genome size variation in taxonomically complex British eyebrights (Euphrasia, Orobanchaceae). Our aim is to document genome size diversity and investigate underlying evolutionary processes shaping variation between individuals, populations and species.
Methods:
We generated genome size data for 192 individuals of diploid and tetraploid Euphrasia and analysed genome size variation in relation to ploidy, taxonomy, population affiliation, and geography. We further compared the genomic repeat content of 30 samples.
Key results:
We found considerable intraspecific genome size variation, and observed isolation-by-distance for genome size in outcrossing diploids. Tetraploid Euphrasia showed contrasting patterns, with genome size increasing with latitude in outcrossing Euphrasia arctica, but with little genome size variation in the highly selfing Euphrasia micrantha. Interspecific differences in genome size and the genomic proportions of repeat sequences were small.
Conclusions:
We show the utility of treating genome size as the outcome of polygenic variation. Like other types of genetic variation, such as single nucleotide polymorphisms, genome size variation may be affected by ongoing hybridisation and the extent of population subdivision. In addition to selection on associated traits, genome size is predicted to be affected indirectly by selection due to pleiotropy of the underlying presence/absence variants.
... DNA barcoding has a wide range of applications, providing a means to identify a sample of plant from the tiniest fragment of leaf, seed or pollen grain. It also provides DNA sequence information that can be used in phylogenetic reconstruction and community ecology (Lim et al., 2014;Ito et al., 2017;Wang et al., 2018). A NBGW research project, initiated in 2019, aimed to investigate grassland ecosystem processes and resilience by DNA metabarcoding the plants, animals, fungi and microbial communities found in Welsh grassland soils. ...
The National Botanic Garden of Wales (NBGW) is dedicated to the research and conservation of biodiversity, sustainability, lifelong learning and the enjoyment of our visitors. NBGW’s Conservation and Research programme includes four major themes: ‘Saving Plants and Fungi’, ‘Saving Pollinators’, ‘International Conservation and Research’ and ‘Science and Society’. This article describes some of NBGW’s activities in three of these core areas, focusing on our work within Wales. 1. Conserving and understanding Welsh plants, fungi and habitats. 2. Conserving pollinating insects and understanding pollinator ecosystem services. 3. Understanding and promoting the importance of plants and gardens for the health and wellbeing of people, wildlife and the environment. NBGW takes a multi-disciplinary approach that involves research, education, engagement, advocacy and direct conservation action. We aim to create a Biophilic Wales by increasing our understanding of the natural world and inspiring people to protect it. Wales is used as a study system to develop models that can applied throughout the world.
