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Leal JL, Milesi P, Hodková E, Zhou Q, James J, Eklund DM, Pyhäjärvi T, Salojärvi J, Lascoux M. Complex Polyploids: Origins, Genomic Composition, and Role of Introgressed Alleles. Syst Biol 2024; 73:392-418. [PMID: 38613229 PMCID: PMC11282369 DOI: 10.1093/sysbio/syae012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 12/18/2023] [Accepted: 03/28/2024] [Indexed: 04/14/2024] Open
Abstract
Introgression allows polyploid species to acquire new genomic content from diploid progenitors or from other unrelated diploid or polyploid lineages, contributing to genetic diversity and facilitating adaptive allele discovery. In some cases, high levels of introgression elicit the replacement of large numbers of alleles inherited from the polyploid's ancestral species, profoundly reshaping the polyploid's genomic composition. In such complex polyploids, it is often difficult to determine which taxa were the progenitor species and which taxa provided additional introgressive blocks through subsequent hybridization. Here, we use population-level genomic data to reconstruct the phylogenetic history of Betula pubescens (downy birch), a tetraploid species often assumed to be of allopolyploid origin and which is known to hybridize with at least four other birch species. This was achieved by modeling polyploidization and introgression events under the multispecies coalescent and then using an approximate Bayesian computation rejection algorithm to evaluate and compare competing polyploidization models. We provide evidence that B. pubescens is the outcome of an autoploid genome doubling event in the common ancestor of B. pendula and its extant sister species, B. platyphylla, that took place approximately 178,000-188,000 generations ago. Extensive hybridization with B. pendula, B. nana, and B. humilis followed in the aftermath of autopolyploidization, with the relative contribution of each of these species to the B. pubescens genome varying markedly across the species' range. Functional analysis of B. pubescens loci containing alleles introgressed from B. nana identified multiple genes involved in climate adaptation, while loci containing alleles derived from B. humilis revealed several genes involved in the regulation of meiotic stability and pollen viability in plant species.
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Affiliation(s)
- J Luis Leal
- Plant Ecology and Evolution, Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
| | - Pascal Milesi
- Plant Ecology and Evolution, Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
- Science for Life Laboratory (SciLifeLab), Uppsala University, 75237 Uppsala, Sweden
| | - Eva Hodková
- Plant Ecology and Evolution, Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
- Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16521 Prague, Czech Republic
| | - Qiujie Zhou
- Plant Ecology and Evolution, Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
| | - Jennifer James
- Plant Ecology and Evolution, Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
| | - D Magnus Eklund
- Physiology and Environmental Toxicology, Department of Organismal Biology, Uppsala University, Norbyvägen 18A, 75236 Uppsala, Sweden
| | - Tanja Pyhäjärvi
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, P.O. Box 65 (Viikinkaari 1), 00014 Helsinki, Finland
- Department of Forest Sciences, University of Helsinki, 00014 Helsinki, Finland
| | - Jarkko Salojärvi
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, P.O. Box 65 (Viikinkaari 1), 00014 Helsinki, Finland
| | - Martin Lascoux
- Plant Ecology and Evolution, Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
- Science for Life Laboratory (SciLifeLab), Uppsala University, 75237 Uppsala, Sweden
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Aihara T, Araki K, Tsumura Y. Cryptic diploid lineage of Betula ermanii at its southern boundary populations in Japan. PLoS One 2024; 19:e0307023. [PMID: 39024350 PMCID: PMC11257223 DOI: 10.1371/journal.pone.0307023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 06/27/2024] [Indexed: 07/20/2024] Open
Abstract
Polyploidy is thought to enable species diversification and adaptation to extreme environments. Resolving the ecological differences between a taxon's ploidy levels would therefore provide important insights into local adaptation and speciation. The genus Betula includes many polyploids, but estimates of their phylogenetic relationships and evolutionary history are uncertain because of cryptic lineages and species. As one of the southern boundary populations of Betula ermanii in Japan has been shown to have distinctive genetic characteristics and traits, the differences in ploidy levels between three southern boundary and various other Japanese B. ermanii populations were investigated using flow cytometry. Leaf and seed morphologies were also compared. Apart from individuals in southern boundary populations, all those sampled were tetraploid. Individuals from the southern boundary populations were mostly diploid, apart from a few from lower altitude Shikoku populations, which were tetraploid. Leaf and seed morphologies differed between tetraploids and diploids. Diploid individuals were characterized by leaves with a heart-shaped base and many leaf teeth, and seeds with relatively longer wings. The diploid populations could be considered a cryptic relict lineage of B. ermanii, and there is a possibility that this lineage is a diploid ancestor of B. ermanii and a relict population of the Sohayaki element. Further investigation of the Japanese Betula phylogenetic relationships would enable an informed discussion of taxonomic revisions.
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Affiliation(s)
- Takaki Aihara
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kyoko Araki
- Graduate School of Science and Technology, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yoshihiko Tsumura
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
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Touchette L, Godbout J, Lamothe M, Porth I, Isabel N. A cryptic syngameon within Betula shrubs revealed: Implications for conservation in changing subarctic environments. Evol Appl 2024; 17:e13689. [PMID: 38633131 PMCID: PMC11022622 DOI: 10.1111/eva.13689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 02/06/2024] [Accepted: 03/20/2024] [Indexed: 04/19/2024] Open
Abstract
Arctic and subarctic ecosystems are rapidly transforming due to global warming, emphasizing the need to understand the genetic diversity and adaptive strategies of northern plant species for effective conservation. This study focuses on Betula glandulosa, a native North American tundra shrub known as dwarf birch, which demonstrates an apparent capacity to adapt to changing climate conditions. To address the taxonomic challenges associated with shrub birches and logistical complexities of sampling in the northernmost areas where species' ranges overlap, we adopted a multicriteria approach. Incorporating molecular data, ploidy level assessment and leaf morphology, we aimed to distinguish B. glandulosa individuals from other shrub birch species sampled. Our results revealed three distinct species and their hybrids within the 537 collected samples, suggesting the existence of a shrub birch syngameon, a reproductive network of interconnected species. Additionally, we identified two discrete genetic clusters within the core species, B. glandulosa, that likely correspond to two different glacial lineages. A comparison between the nuclear and chloroplast SNP data emphasizes a long history of gene exchange between different birch species and genetic clusters. Furthermore, our results highlight the significance of incorporating interfertile congeneric species in conservation strategies and underscores the need for a holistic approach to conservation in the context of climate change, considering the complex dynamics of species interactions. While further research will be needed to describe this shrub birches syngameon and its constituents, this study is a first step in recognizing its existence and disseminating awareness among ecologists and conservation practitioners. This biological phenomenon, which offers evolutionary flexibility and resilience beyond what its constituent species can achieve individually, may have significant ecological implications.
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Affiliation(s)
- Lyne Touchette
- Department of Wood and Forest SciencesUniversité LavalQuebecQuebecCanada
- Natural Resources Canada, Canadian Forest ServiceLaurentian Forestry CentreQuebecQuebecCanada
- Centre for Forest ResearchUniversité LavalQuebecQuebecCanada
| | - Julie Godbout
- Ministère des Ressources naturelles et des Forêts, Direction de la recherche forestièreQuébecQuébecCanada
| | - Manuel Lamothe
- Natural Resources Canada, Canadian Forest ServiceLaurentian Forestry CentreQuebecQuebecCanada
| | - Ilga Porth
- Department of Wood and Forest SciencesUniversité LavalQuebecQuebecCanada
- Centre for Forest ResearchUniversité LavalQuebecQuebecCanada
| | - Nathalie Isabel
- Natural Resources Canada, Canadian Forest ServiceLaurentian Forestry CentreQuebecQuebecCanada
- Centre for Forest ResearchUniversité LavalQuebecQuebecCanada
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Zhang H, Ding J, Holstein N, Wang N. Betula mcallisteri sp. nov. (sect. Acuminatae, Betulaceae), a new diploid species overlooked in the wild and in cultivation, and its relation to the widespread B. luminifera. FRONTIERS IN PLANT SCIENCE 2023; 14:1113274. [PMID: 37324661 PMCID: PMC10268003 DOI: 10.3389/fpls.2023.1113274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 04/19/2023] [Indexed: 06/17/2023]
Abstract
Taxa are traditionally identified using morphological proxies for groups of evolutionarily isolated populations. These proxies are common characters deemed by taxonomists as significant. However, there is no general rule on which character or sets of characters are appropriate to circumscribe taxa, leading to discussions and uncertainty. Birch species are notoriously hard to identify due to strong morphological variability and factors such as hybridization and the existence of several ploidy levels. Here, we present evidence for an evolutionarily isolated line of birches from China that are not distinguishable by traditionally assumed taxon recognition proxies, such as fruit or leaf characters. We have discovered that some wild material in China and some cultivated in the Royal Botanic Gardens Edinburgh, formerly recognized as Betula luminifera, differ from other individuals by having a peeling bark and a lack of cambial fragrance. We use restriction site-associated DNA sequencing and flow cytometry to study the evolutionary status of the unidentified Betula samples to assess the extent of hybridization between the unidentified Betula samples and typical B. luminifera in natural populations. Molecular analyses show the unidentified Betula samples as a distinct lineage and reveal very little genetic admixture between the unidentified samples and B. luminifera. This may also be facilitated by the finding that B. luminifera is tetraploid, while the unidentified samples turned out to be diploid. We therefore conclude that the samples represent a yet unrecognized species, which is here described as Betula mcallisteri.
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Affiliation(s)
- Huayu Zhang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of The Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
| | - Junyi Ding
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of The Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
| | - Norbert Holstein
- Department of Life Sciences, The Natural History Museum, London, United Kingdom
| | - Nian Wang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of The Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
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Hutang GR, Tong Y, Zhu XG, Gao LZ. Genome size variation and polyploidy prevalence in the genus Eragrostis are associated with the global dispersal in arid area. FRONTIERS IN PLANT SCIENCE 2023; 14:1066925. [PMID: 36993864 PMCID: PMC10040770 DOI: 10.3389/fpls.2023.1066925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 02/28/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND Biologists have long debated the drivers of the genome size evolution and variation ever since Darwin. Assumptions for the adaptive or maladaptive consequences of the associations between genome sizes and environmental factors have been proposed, but the significance of these hypotheses remains controversial. Eragrostis is a large genus in the grass family and is often used as crop or forage during the dry seasons. The wide range and complex ploidy levels make Eragrostis an excellent model for investigating how the genome size variation and evolution is associated with environmental factors and how these changes can ben interpreted. METHODS We reconstructed the Eragrostis phylogeny and estimated genome sizes through flow cytometric analyses. Phylogenetic comparative analyses were performed to explore how genome size variation and evolution is related to their climatic niches and geographical ranges. The genome size evolution and environmental factors were examined using different models to study the phylogenetic signal, mode and tempo throughout evolutionary history. RESULTS Our results support the monophyly of Eragrostis. The genome sizes in Eragrostis ranged from ~0.66 pg to ~3.80 pg. We found that a moderate phylogenetic conservatism existed in terms of the genome sizes but was absent from environmental factors. In addition, phylogeny-based associations revealed close correlations between genome sizes and precipitation-related variables, indicating that the genome size variation mainly caused by polyploidization may have evolved as an adaptation to various environments in the genus Eragrostis. CONCLUSION This is the first study to take a global perspective on the genome size variation and evolution in the genus Eragrostis. Our results suggest that the adaptation and conservatism are manifested in the genome size variation, allowing the arid species of Eragrostis to spread the xeric area throughout the world.
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Affiliation(s)
- Ge-Ran Hutang
- Germplasm Bank of Wild Species in Southwestern China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yan Tong
- Germplasm Bank of Wild Species in Southwestern China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Xun-Ge Zhu
- Germplasm Bank of Wild Species in Southwestern China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Li-Zhi Gao
- Germplasm Bank of Wild Species in Southwestern China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- Engineering Research Center for Selecting and Breeding New Tropical Crop Varieties, Ministry of Education, College of Tropical Crops, Hainan University, Haikou, China
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Nocchi G, Wang J, Yang L, Ding J, Gao Y, Buggs RJA, Wang N. Genomic signals of local adaptation and hybridization in Asian white birch. Mol Ecol 2023; 32:595-612. [PMID: 36394364 DOI: 10.1111/mec.16788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 11/03/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
Abstract
Disentangling the numerous processes that affect patterns of genome-wide diversity in widespread tree species has important implications for taxonomy, conservation, and forestry. Here, we investigate the population genomic structure of Asian white birch (Betula platyphylla) in China and seek to explain it in terms of hybridization, demography and adaptation. We generate whole genome sequence data from 83 individuals across the species range in China. Combining this with an existing data set for 79 European and Russian white birches, we show a clear distinction between B. pendula and B. platyphylla, which have sometimes been lumped taxonomically. Genomic diversity of B. platyphylla in north-western China and Central Russia is affected greatly by hybridization with B. pendula. Excluding these hybridized populations, B. platyphylla in China has a linear distribution from north-eastern to south-western China, along the edge of the inland mountainous region. Within this distribution, three genetic clusters are found, which we model as long diverged with subsequent episodes of gene flow. Patterns of covariation between allele frequencies and environmental variables in B. platyphylla suggest the role of natural selection in the distribution of diversity at 7609 SNPs of which 3767 were significantly differentiated among the genetic clusters. The putative adaptive SNPs are distributed throughout the genome and span 1633 genic regions. Of these genic regions, 87 were previously identified as candidates for selective sweeps in Eurasian B. pendula. We use the 7609 environmentally associated SNPs to estimate the risk of nonadaptedness for each sequenced B. platyphylla individual under a scenario of future climate change, highlighting areas where populations may be under future threat from rising temperatures.
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Affiliation(s)
- Gabriele Nocchi
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK.,Royal Botanic Gardens Kew, Richmond, Surrey, UK
| | - Jing Wang
- Key Laboratory for Bio-resources and Eco-environment, College of Life Science, Sichuan University, Chengdu, China
| | - Long Yang
- Agricultural Big-Data Research Centre and College of Plant Protection, Shandong Agricultural University, Tai'an, China
| | - Junyi Ding
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai'an, China.,Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai'an, China
| | - Ying Gao
- Agricultural Big-Data Research Centre and College of Plant Protection, Shandong Agricultural University, Tai'an, China
| | - Richard J A Buggs
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK.,Royal Botanic Gardens Kew, Richmond, Surrey, UK
| | - Nian Wang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai'an, China.,Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai'an, China.,State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, China
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Wang L, Ding J, Borrell JS, Cheek M, McAllister HA, Wang F, Liu L, Zhang H, Zhang Q, Wang Y, Wang N. Molecular and morphological analyses clarify species delimitation in section Costatae and reveal Betula buggsii sp. nov. (sect. Costatae, Betulaceae) in China. ANNALS OF BOTANY 2022; 129:415-428. [PMID: 35018419 PMCID: PMC8944703 DOI: 10.1093/aob/mcac001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND AIMS Delineating closely related and morphologically similar species is difficult. Here, we integrate morphology, genetics, ploidy and geography to resolve species and subspecies boundaries in four trees of section Costatae (genus Betula): Betula ashburneri, B. costata, B. ermanii and B. utilis, as well as multiple subspecies and polyploid races. METHODS We genotyped 371 individuals (20-133 per species) from 51 populations at 15 microsatellite markers, as well as a subset of individuals, using restriction-site associated DNA sequencing and nuclear internal transcribed spacers. We determined the ploidy level of eight individuals using flow cytometry and characterized leaf variation for a subset of 109 individuals by morphometric analysis. KEY RESULTS Integration of multiple lines of evidence suggested a series of revisions to the taxonomy of section Costatae. Betula costata and B. ermanii were found to be valid. Molecular and leaf morphology analyses revealed little differentiation between diploid B. albosinensis and some samples of B. utilis ssp. utilis. By contrast, other B. utilis ssp. utilis samples and ssp. albosinensis formed a morphological continuum but differed based on genetics. Specifically, B. utilis ssp. albosinensis was divided into two groups with group I genetically similar to B. utilis ssp. utilis and group II, a distinct cluster, proposed as the new diploid species Betula buggsii sp. nov. Phylogenomic analysis based on 2285 620 single nucleotide polymorphisms identified a well-supported monophyletic clade of B. buggsii. Morphologically, B. buggsii is characterized by elongated lenticels and a distinct pattern of bark peeling and may be geographically restricted to the Qinling-Daba Mountains. CONCLUSIONS Our integrated approach identifies six taxa within section Costatae: B. ashburneri, B. buggsii, B. costata, B. utilis ssp. utilis, B. utilis ssp. albosinensis and B. ermanii. Our research demonstrates the value of an integrative approach using morphological, geographical, genetic and ploidy-level data for species delineation.
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Affiliation(s)
| | | | | | | | - Hugh A McAllister
- School of Life Sciences, Biosciences Building, University of Liverpool, Crown Street, Liverpool, UK
| | - Feifei Wang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
| | - Lu Liu
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
| | - Huayu Zhang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
| | - Qiufeng Zhang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
| | - Yiming Wang
- State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai’an, China
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
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Singewar K, Kersten B, Moschner CR, Hartung E, Fladung M. Transcriptome analysis of North American sweet birch (Betula lenta) revealed a higher expression of genes involved in the biosynthesis of secondary metabolites than European silver birch (B. pendula). JOURNAL OF PLANT RESEARCH 2021; 134:1253-1264. [PMID: 34499285 PMCID: PMC8514364 DOI: 10.1007/s10265-021-01343-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
The North American Betula lenta L. (sweet birch) has been used for medicinal reasons for centuries by native Americans. Although sophisticated technologies have rapidly been developed, a large information gap has been observed regarding genetic regulators of medicinally important compounds in sweet birch. Very little is known on the different genes involved in secondary metabolic biosynthesis in sweet birch. To gain a deeper insight into genetic factors, we performed a transcriptome analysis of each three biological samples from different independent trees of sweet and European silver birch (B. pendula Roth). This allowed us to precisely quantify the transcripts of about 24,000 expressed genes including 29 prominent candidate genes putatively involved in the biosynthesis of secondary metabolites like terpenoids, and aromatic benzoic acids. A total number of 597 genes were differentially expressed between B. lenta and B. pendula, while 264 and 210 genes showed upregulation in the bark and leaf of B. lenta, respectively. Moreover, we identified 39 transcriptional regulatory elements, involved in secondary metabolite biosynthesis, upregulated in B. lenta. Our study demonstrated the potential of RNA sequencing to identify candidate genes interacting in secondary metabolite biosynthesis in sweet birch. The candidate genes identified in this study could be subjected to genetic engineering to functionally characterize them in sweet birch. This knowledge can be beneficial to the increase of therapeutically important compounds.
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Affiliation(s)
- Kiran Singewar
- Institute of Agricultural Process Engineering, Christian-Albrechts University of Kiel, Max-Eyth- Str. 6, 24118, Kiel, Germany
- Thuenen-Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany
| | - Birgit Kersten
- Thuenen-Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany
| | - Christian R Moschner
- Institute of Agricultural Process Engineering, Christian-Albrechts University of Kiel, Max-Eyth- Str. 6, 24118, Kiel, Germany
| | - Eberhard Hartung
- Institute of Agricultural Process Engineering, Christian-Albrechts University of Kiel, Max-Eyth- Str. 6, 24118, Kiel, Germany
| | - Matthias Fladung
- Thuenen-Institute of Forest Genetics, Sieker Landstraße 2, 22927, Grosshansdorf, Germany.
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Rojo J, Oteros J, Picornell A, Maya-Manzano JM, Damialis A, Zink K, Werchan M, Werchan B, Smith M, Menzel A, Timpf S, Traidl-Hoffmann C, Bergmann KC, Schmidt-Weber CB, Buters J. Effects of future climate change on birch abundance and their pollen load. GLOBAL CHANGE BIOLOGY 2021; 27:5934-5949. [PMID: 34363285 DOI: 10.1111/gcb.15824] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Climate change impacts on the structure and function of ecosystems will worsen public health issues like allergic diseases. Birch trees (Betula spp.) are important sources of aeroallergens in Central and Northern Europe. Birches are vulnerable to climate change as these trees are sensitive to increased temperatures and summer droughts. This study aims to examine the effect of climate change on airborne birch pollen concentrations in Central Europe using Bavaria in Southern Germany as a case study. Pollen data from 28 monitoring stations in Bavaria were used in this study, with time series of up 30 years long. An integrative approach was used to model airborne birch pollen concentrations taking into account drivers influencing birch tree abundance and birch pollen production and projections made according to different climate change and socioeconomic scenarios. Birch tree abundance is projected to decrease in parts of Bavaria at different rates, depending on the climate scenario, particularly in current centres of the species distribution. Climate change is expected to result in initial increases in pollen load but, due to the reduction in birch trees, the amount of airborne birch pollen will decrease at lower altitudes. Conversely, higher altitude areas will experience expansions in birch tree distribution and subsequent increases in airborne birch pollen in the future. Even considering restrictions for migration rates, increases in pollen load are likely in Southwestern areas, where positive trends have already been detected during the last three decades. Integrating models for the distribution and abundance of pollen sources and the drivers that control birch pollen production allowed us to model airborne birch pollen concentrations in the future. The magnitude of changes depends on location and climate change scenario.
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Affiliation(s)
- Jesús Rojo
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technische Universität München/Helmholtz Center Munich, Munich, Germany
- Department of Pharmacology, Pharmacognosy and Botany, Complutense University of Madrid, Madrid, Spain
| | - Jose Oteros
- Department of Botany, Ecology and Plant Physiology, University of Cordoba, Cordoba, Spain
| | - Antonio Picornell
- Department of Botany and Plant Physiology, University of Malaga, Malaga, Spain
| | - José M Maya-Manzano
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technische Universität München/Helmholtz Center Munich, Munich, Germany
| | - Athanasios Damialis
- Department of Ecology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
- Department of Environmental Medicine, University of Augsburg, Augsburg, Germany
- Helmholtz Center Munich - German Research Center for Environmental Health, Augsburg, Germany
| | - Katrin Zink
- Bayerisches Landesamt für Umwelt, Schwerpunkt Klima und Energie, Referat KliZ: Klima-Zentrum, Hof/Saale, Germany
| | - Matthias Werchan
- German Pollen Information Service Foundation (PID), Berlin, Germany
| | - Barbora Werchan
- German Pollen Information Service Foundation (PID), Berlin, Germany
| | - Matt Smith
- School of Science and the Environment, University of Worcester, Worcester, UK
| | - Annette Menzel
- School of Life Sciences, Technische Universität München, Freising, Germany
| | - Sabine Timpf
- Institute of Geography, Geoinformatics Group, University of Augsburg, Augsburg, Germany
| | - Claudia Traidl-Hoffmann
- Department of Environmental Medicine, University of Augsburg, Augsburg, Germany
- Helmholtz Center Munich - German Research Center for Environmental Health, Augsburg, Germany
| | - Karl-Christian Bergmann
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Carsten B Schmidt-Weber
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technische Universität München/Helmholtz Center Munich, Munich, Germany
| | - Jeroen Buters
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technische Universität München/Helmholtz Center Munich, Munich, Germany
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10
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Ice nucleation in a Gram-positive bacterium isolated from precipitation depends on a polyketide synthase and non-ribosomal peptide synthetase. ISME JOURNAL 2021; 16:890-897. [PMID: 34689184 PMCID: PMC8857237 DOI: 10.1038/s41396-021-01140-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/03/2021] [Accepted: 10/05/2021] [Indexed: 11/22/2022]
Abstract
Earth’s radiation budget and frequency and intensity of precipitation are influenced by aerosols with ice nucleation activity (INA), i.e., particles that catalyze the formation of ice. Some bacteria, fungi, and pollen are among the most efficient ice nucleators but the molecular basis of INA is poorly understood in most of them. Lysinibacillus parviboronicapiens (Lp) was previously identified as the first Gram-positive bacterium with INA. INA of Lp is associated with a secreted, nanometer-sized, non-proteinaceous macromolecule or particle. Here a combination of comparative genomics, transcriptomics, and a mutant screen showed that INA in Lp depends on a type I iterative polyketide synthase and a non-ribosomal peptide synthetase (PKS-NRPS). Differential filtration in combination with gradient ultracentrifugation revealed that the product of the PKS-NRPS is associated with secreted particles of a density typical of extracellular vesicles and electron microscopy showed that these particles consist in “pearl chain”-like structures not resembling any other known bacterial structures. These findings expand our knowledge of biological INA, may be a model for INA in other organisms for which the molecular basis of INA is unknown, and present another step towards unraveling the role of microbes in atmospheric processes.
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11
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Becher H, Powell RF, Brown MR, Metherell C, Pellicer J, Leitch IJ, Twyford AD. The nature of intraspecific and interspecific genome size variation in taxonomically complex eyebrights. ANNALS OF BOTANY 2021; 128:639-651. [PMID: 34318876 PMCID: PMC8422891 DOI: 10.1093/aob/mcab102] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
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 hybridization 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.
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Affiliation(s)
- Hannes Becher
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Max R Brown
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
- Wellcome Trust Genome Campus, Hinxton, Saffron Walden, UK
| | - Chris Metherell
- Botanical Society of Britain and Ireland, Harpenden, Hertfordshire, UK
| | - Jaume Pellicer
- Royal Botanic Gardens, Kew, Richmond, Surrey, UK
- Institut Botànic de Barcelona (IBB, CSIC-Ajuntament de Barcelona), Barcelona, Spain
| | | | - Alex D Twyford
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
- Royal Botanic Garden Edinburgh, Edinburgh, UK
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12
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Yang YY, Qu XJ, Zhang R, Stull GW, Yi TS. Plastid phylogenomic analyses of Fagales reveal signatures of conflict and ancient chloroplast capture. Mol Phylogenet Evol 2021; 163:107232. [PMID: 34129935 DOI: 10.1016/j.ympev.2021.107232] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 05/21/2021] [Accepted: 06/10/2021] [Indexed: 11/17/2022]
Abstract
Plastid phylogenomic analyses have shed light on many recalcitrant relationships across the angiosperm Tree of Life and continue to play an important role in plant phylogenetics alongside nuclear data sets given the utility of plastomes for revealing ancient and recent introgression. Here we conduct a plastid phylogenomic study of Fagales, aimed at exploring contentious relationships (e.g., the placement of Myricaceae and some intergeneric relationships in Betulaceae, Juglandaceae, and Fagaceae) and dissecting conflicting phylogenetic signals across the plastome. Combining 102 newly sequenced samples with publically available plastomes, we analyzed a dataset including 256 species and 32 of the 34 total genera of Fagales, representing the largest plastome-based study of the order to date. We find strong support for a sister relationship between Myricaceae and Juglandaceae, as well as strongly supported conflicting signal for alternative generic relationships in Betulaceae and Juglandaceae. These conflicts highlight the sensitivity of plastid phylogenomic analyses to genic composition, perhaps due to the prevalence of uninformative loci and heterogeneity in signal across different regions of the plastome. Phylogenetic relationships were geographically structured in subfamily Quercoideae, with Quercus being non-monophyletic and its sections forming clades with co-distributed Old World or New World genera of Quercoideae. Compared against studies based on nuclear genes, these results suggest extensive introgression and chloroplast capture in the early diversification of Quercus and Quercoideae. This study provides a critical plastome perspective on Fagales phylogeny, setting the stage for future studies employing more extensive data from the nuclear genome.
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Affiliation(s)
- Ying-Ying Yang
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China; CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Xiao-Jian Qu
- Shandong Provincial Key Laboratory of Plant Stress Research, College of Life Sciences, Shandong Normal University, Jinan, Shangdong 250014, China
| | - Rong Zhang
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Gregory W Stull
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China.
| | - Ting-Shuang Yi
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China; CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China.
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13
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Tarieiev AS, Gailing O, Krutovsky KV. ITS secondary structure reconstruction to resolve taxonomy and phylogeny of the Betula L. genus. PeerJ 2021; 9:e10889. [PMID: 33828907 PMCID: PMC7996101 DOI: 10.7717/peerj.10889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/12/2021] [Indexed: 01/31/2023] Open
Abstract
The taxonomy and phylogeny of the Betula L. genus remain unresolved and are very difficult to assess due to several factors, especially because of frequent hybridization among different species. In the current study, we used nucleotide sequences of two internal transcribed spacer regions (ITS1 and ITS2), which are commonly used as phylogenetic markers. In addition to their nucleotide variation we reconstructed their secondary structure and used it to resolve phylogenetic relationships of some birch species. We explored whether consideration of secondary structure in phylogenetic analyses based on neighbor-joining, maximum parsimony, maximum likelihood, and Bayesian inference methods would help us obtain more solid support of the reconstructed phylogenetic trees. The results were not unambiguous. There were only a few clades with higher support when secondary structure was included into analysis. The phylogenetic trees generated using different methods were mostly in agreement with each other. However, the resolving power of these markers is still insufficient to reliably discriminate some closely related species. To achieve this aim more reliably there is a need for application of modern genomic approaches in combination with traditional ones.
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Affiliation(s)
- Andrii S. Tarieiev
- Department of Forest Genetics and Forest Tree Breeding, Georg-August University of Göttingen, Göttingen, Germany
| | - Oliver Gailing
- Department of Forest Genetics and Forest Tree Breeding, Georg-August University of Göttingen, Göttingen, Germany
- Center for Integrated Breeding Research, Georg-August University of Göttingen, Göttingen, Germany
| | - Konstantin V. Krutovsky
- Department of Forest Genetics and Forest Tree Breeding, Georg-August University of Göttingen, Göttingen, Germany
- Center for Integrated Breeding Research, Georg-August University of Göttingen, Göttingen, Germany
- Laboratory of Forest Genomics, Genome Research and Education Center, Institute of Fundamental Biology and Biotechnology, Siberian Federal University, Krasnoyarsk, Russia
- Laboratory of Population Genetics, N.I. Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
- Department of Ecosystem Science and Management, Texas A&M University, College Station, TX, United States of America
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14
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Wang N, Kelly LJ, McAllister HA, Zohren J, Buggs RJA. Resolving phylogeny and polyploid parentage using genus-wide genome-wide sequence data from birch trees. Mol Phylogenet Evol 2021; 160:107126. [PMID: 33647400 DOI: 10.1016/j.ympev.2021.107126] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/15/2021] [Accepted: 02/22/2021] [Indexed: 01/04/2023]
Abstract
Numerous plant genera have a history including frequent hybridisation and polyploidisation (allopolyploidisation), which means that their phylogeny is a network of reticulate evolution that cannot be accurately depicted as a bifurcating tree with a single tip per species. The genus Betula, which contains many ecologically important tree species, is a case in point. We generated genome-wide sequence reads for 27 diploid and 36 polyploid Betula species or subspecies using restriction site associated DNA (RAD) sequences. These reads were assembled into contigs with a mean length of 675 bp. We reconstructed the evolutionary relationships among diploid Betula species using both supermatrix (concatenation) and species tree methods. We identified the closest diploid relatives of the polyploids according to the relative rates at which reads from polyploids mapped to contigs from different diploid species within a concatenated reference sequence. By mapping reads from allopolyploids to their different putative diploid relatives we assembled contigs from the putative sub-genomes of allopolyploid taxa. We used these to build new phylogenies that included allopolyploid sub-genomes as separate tips. This approach yielded a highly evidenced phylogenetic hypothesis for the genus Betula, including the complex reticulate origins of the majority of its polyploid taxa. Our phylogeny divides the genus into two well supported clades, which, interestingly, differ in their seed-wing morphology. We therefore propose to split Betula into two subgenera.
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Affiliation(s)
- Nian Wang
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK; State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River, College of Forestry, Shandong Agricultural University, Tai'an 271018, China
| | - Laura J Kelly
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK; Royal Botanic Gardens Kew, Richmond, Surrey TW9 3AB, UK
| | - Hugh A McAllister
- Institute of Integrative Biology, Biosciences Building, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK
| | - Jasmin Zohren
- Sex Chromosome Biology Lab, the Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Richard J A Buggs
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK; Royal Botanic Gardens Kew, Richmond, Surrey TW9 3AB, UK.
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15
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The Application of Flow Cytometry for Estimating Genome Size, Ploidy Level Endopolyploidy, and Reproductive Modes in Plants. Methods Mol Biol 2021; 2222:325-361. [PMID: 33301101 DOI: 10.1007/978-1-0716-0997-2_17] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Over the years, the amount of DNA in a nucleus (genome size) has been estimated using a variety of methods, but increasingly, flow cytometry (FCM) has become the method of choice. The popularity of this technique lies in the ease of sample preparation and in the large number of particles (i.e., nuclei) that can be analyzed in a very short period of time. This chapter presents a step-by-step guide to estimating the nuclear DNA content of plant nuclei using FCM. Attempting to serve as a tool for daily laboratory practice, we list, in detail, the equipment required, specific reagents and buffers needed, as well as the most frequently used protocols to carry out nuclei isolation. In addition, solutions to the most common problems that users may encounter when working with plant material and troubleshooting advice are provided. Finally, information about the correct terminology to use and the importance of obtaining chromosome counts to avoid cytological misinterpretations of the FCM data are discussed.
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16
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Medvedeva S, Cherepanova O, Tolkach O, Ponomarev V, Malosieva G. TrnL-trnfF cpDNA polymorphism in some representatives of the genus Betula. BIO WEB OF CONFERENCES 2021. [DOI: 10.1051/bioconf/20213500017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present preliminary results of the trnL-trnF cpDNA region analysis for some representatives of the g. Betula, out of which B. procurva can be considered the most interesting. The disjunctive range of this species is confined to the mountain system in southeast Central Asia (Pamir-Alai). The occurrence of the birch is isolated from the main range in the mountainous part of the Urals, in the boreal forests zone and in the Trans-Ural forest-steppe. Due to high interspecific hybridization and population variability of the g. Betula, doubts were raised about the correct identification of the representatives of B. procurva. The studied genetic variability and population structure of B. procurva, B. nana, B. pubescens, B. turkestanica, B. tianshanica and B. pendula species indicate active introgression and hybridization processes. Polymorphism in all groups is significantly reduced, increasing slightly when comparing the most distant groups. The matching of the B. procurva cpDNA haplotypes (GBS) with B. pendula, B. nana, and B. pubescens shows that this trnL-trnF cpDNA site cannot be used for molecular identification of birch species by barcoding as a single marker, but this marker use is possible for determination of certain B. procurva population. Based on the studied cpDNA region (trnL-F) we found a clear geographic subdivision in B. procurva populations of the Trans-Urals and Central Asia,.
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17
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Chamberlain CJ, Cook BI, Morales-Castilla I, Wolkovich EM. Climate change reshapes the drivers of false spring risk across European trees. THE NEW PHYTOLOGIST 2021; 229:323-334. [PMID: 32767753 DOI: 10.1111/nph.16851] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023]
Abstract
Temperate forests are shaped by late spring freezes after budburst - false springs - which may shift with climate change. Research to date has generated conflicting results, potentially because few studies focus on the multiple underlying drivers of false spring risk. Here, we assessed the effects of mean spring temperature, distance from the coast, elevation and the North Atlantic Oscillation (NAO) using PEP725 leafout data for six tree species across 11 648 sites in Europe, to determine which were the strongest predictors of false spring risk and how these predictors shifted with climate change. All predictors influenced false spring risk before recent warming, but their effects have shifted in both magnitude and direction with warming. These shifts have potentially magnified the variation in false spring risk among species with an increase in risk for early-leafout species (i.e. Aesculus hippocastanum, Alnus glutinosa, Betula pendula) compared with a decline or no change in risk among late-leafout species (i.e. Fagus sylvatica, Fraxinus excelsior, Quercus robur). Our results show how climate change has reshaped the drivers of false spring risk, complicating forecasts of future false springs, and potentially reshaping plant community dynamics given uneven shifts in risk across species.
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Affiliation(s)
- Catherine J Chamberlain
- Arnold Arboretum of Harvard University, 1300 Centre Street, Boston, MA, 02131, USA
- Organismic & Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA, 02138, USA
| | - Benjamin I Cook
- NASA Goddard Institute for Space Studies, New York, NY, 10025, USA
| | - Ignacio Morales-Castilla
- GloCEE - Global Change Ecology and Evolution Group, Department of Life Sciences, Universidad de Alcalá, Alcalá de Henares, 28805, Spain
- Department of Environmental Science and Policy, George Mason University, Fairfax, VA, 22030, USA
| | - E M Wolkovich
- Arnold Arboretum of Harvard University, 1300 Centre Street, Boston, MA, 02131, USA
- Organismic & Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA, 02138, USA
- Forest & Conservation Sciences, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
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18
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Shiotani Y, Fukuda T, Marchuk EA, Petrunenko EA, Krestov PV, Bondarchuk SN, Nishikawa Y, Shimamura T, Fujimura Y, Nakamura K. Merger of Betula tatewakiana (Betulaceae) from northern Japan with northeast Asian B. ovalifolia based on ploidy level. PHYTOKEYS 2020; 170:83-91. [PMID: 33442325 PMCID: PMC7773712 DOI: 10.3897/phytokeys.170.58585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 11/20/2020] [Indexed: 06/12/2023]
Abstract
It has been controversial whether Betula tatewakiana, a dwarf birch distributed in Hokkaido of northern Japan, is an endemic species or a synonym of B. ovalifolia broadly distributed in northeast Asia. The endemic hypothesis is based on the idea that B. tatewakiana is diploid while B. ovalifolia is tetraploid and that they are separated based on the ploidy level; however, no chromosome data have actually been published before. Resolving the taxonomic problem is crucial also in judging the conservation priority of B. tatewakiana in a global perspective. Our chromosome observation revealed that B. tatewakiana is tetraploid as well as B. ovalifolia. We also conducted morphological observations and clarified that B. tatewakiana is morphologically identical to B. ovalifolia in white hairs and dense resinous glands respectively on adaxial and abaxial leaf surfaces, in which they differ from closely related species in the same section Fruticosae. We conclude that the hypothesis that B. tatewakiana is a Hokkaido endemic based on the ploidy level is not supported and that B. tatewakiana should be merged with B. ovalifolia.
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Affiliation(s)
- Yuki Shiotani
- Division of Biosphere Science, Graduate School of Environment Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Tomoko Fukuda
- College of Liberal Arts and Sciences, Mie University, Tsu 514-8507, Japan
| | - Elena A. Marchuk
- Botanical Garden-Institute, Far Eastern Branch of the Russian Academy of Sciences, Makovskii Str. 142, Vladivostok, 690024, Russia
| | - Ekaterina A. Petrunenko
- Botanical Garden-Institute, Far Eastern Branch of the Russian Academy of Sciences, Makovskii Str. 142, Vladivostok, 690024, Russia
| | - Pavel V. Krestov
- Botanical Garden-Institute, Far Eastern Branch of the Russian Academy of Sciences, Makovskii Str. 142, Vladivostok, 690024, Russia
| | - Svetlana N. Bondarchuk
- Sikhote–Alin State Nature Biosphere Reserve, Ministry of Nature Resources and Environment, Terney, 692150, Russia
| | - Yoko Nishikawa
- Institute of Environmental Sciences, Hokkaido Research Organization, Sapporo 060-0819, Japan
| | - Takashi Shimamura
- Institute of Environmental Sciences, Hokkaido Research Organization, Sapporo 060-0819, Japan
| | - Yoshiyasu Fujimura
- Research & Development Center, Nippon Koei Co. Ltd., Tsukuba 300-1259, Japan
| | - Koh Nakamura
- Botanic Garden, Field Science Center for Northern Biosphere, Hokkaido University, Sapporo 060-0003, Japan
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19
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Singewar K, Moschner CR, Hartung E, Fladung M. Identification and analysis of key genes involved in methyl salicylate biosynthesis in different birch species. PLoS One 2020; 15:e0240246. [PMID: 33031447 PMCID: PMC7544025 DOI: 10.1371/journal.pone.0240246] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 09/22/2020] [Indexed: 01/10/2023] Open
Abstract
Species of the perennial woody plant genus Betula dominate subalpine forests and play a significant role in preserving biological diversity. In addition to their conventional benefits, birches synthesize a wide range of secondary metabolites having pharmacological significance. Methyl salicylate (MeSA) is one of these naturally occurring compounds constitutively produced by different birch species. MeSA is therapeutically important in human medicine for muscle injuries and joint pain. However, MeSA is now mainly produced synthetically due to a lack of information relating to MeSA biosynthesis and regulation. In this study, we performed a comprehensive bioinformatics analysis of two candidate genes mediating MeSA biosynthesis, SALICYLIC ACID METHYLTRANSFERASE (SAMT) and SALICYLIC ACID-BINDING PROTEIN 2 (SABP2), of high (B. lenta, B. alleghaniensis, B. medwediewii, and B. grossa) and low (B. pendula, B. utilis, B. alnoides, and B. nana) MeSA-producing birch species. Phylogenetic analyses of SAMT and SABP2 genes and homologous genes from other plant species confirmed their evolutionary relationships. Multiple sequence alignments of the amino acid revealed the occurrence of important residues for substrate specificity in SAMT and SABP2. The analysis of cis elements in different birches indicated a functional multiplicity of SAMT and SABP2 and provided insights into the regulation of both genes. We successfully developed six prominent single nucleotide substitution markers that were validated with 38 additional birch individuals to differentiate high and low MeSA-producing birch species. Relative tissue-specific expression analysis of SAMT in leaf and bark tissue of two high and two low MeSA-synthesizing birches revealed a high expression in the bark of both high MeSA-synthesizing birches. In contrast, SABP2 expression in tissues revealed indifferent levels of expression between species belonging to the two groups. The comparative expression and bioinformatics analyses provided vital information that could be used to apply plant genetic engineering technology in the mass production of organic MeSA.
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Affiliation(s)
- Kiran Singewar
- Institute of Agricultural Process Engineering, Christian-Albrechts University of Kiel, Kiel, Schleswig-Holstein, Germany
- Thünen Institute of Forest Genetics, Grosshansdorf, Schleswig-Holstein, Germany
| | - Christian R. Moschner
- Institute of Agricultural Process Engineering, Christian-Albrechts University of Kiel, Kiel, Schleswig-Holstein, Germany
| | - Eberhard Hartung
- Institute of Agricultural Process Engineering, Christian-Albrechts University of Kiel, Kiel, Schleswig-Holstein, Germany
| | - Matthias Fladung
- Thünen Institute of Forest Genetics, Grosshansdorf, Schleswig-Holstein, Germany
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20
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Huang J, Guo Z, Tang S, Ren W, Chu G, Wang L, Zhao L, Yu R, Xu Y, Ding Y, Zang R. Floristic composition and plant diversity in distribution areas of native species congeneric with Betula halophila in Xinjiang, northwest China. NATURE CONSERVATION 2020. [DOI: 10.3897/natureconservation.42.54735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Betula halophila, a wild plant with extremely small populations, is endemic to Xinjiang, northwest China. Its wild populations have declined severely in the field. Understanding the patterns of floristic composition where congeneric species of B. halophila are distributed and their determinants is a necessary step to restore the wild populations. Based on literature records, specimen information, shared public data and field survey data, the patterns of floristic composition, diversity and environmental conditions of seed flora within the distribution areas of five native species (i.e. B. tianschanica, B. microphylla, B. pendula, B. rotundifolia and B. humilis), congeneric with B. halophila, were examined. The results are as follows. (1) There were 3013 species, 693 genera and 108 families of seed plants in the distribution area of these congeneric species of B. halophila, which accounted for 86.16%, 94.54% and 93.91% of the total seed plants in Xinjiang, respectively. (2) The family composition of seed flora in the distribution area of these congeneric species of B. halophila was mainly cosmopolitan; the genus composition of seed flora was dominated by temperate, mainly of northern temperate and Mediterranean components. (3) There are no significant differences existing in plant richness amongst the areas where each of the five congeneric species (B. tianshchanica, B. microphylla, B. pendula, B. rotundifolia and B. humilis) are distributed. (4) The influence of climate factors on species richness is significant across the whole distribution areas of the Betula genus, while the main environmental factors determining species richness are different amongst distribution areas of different species. Climate factors impacted significantly on species richness in distribution areas of tree species, but not in distribution areas of shrub species. This study provides a preliminary guideline for the conservation of B. halophila, a wild plant with extremely small populations in the field.
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21
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Weber J, Schwark L. Epicuticular wax lipid composition of endemic European Betula species in a simulated ontogenetic/diagenetic continuum and its application to chemotaxonomy and paleobotany. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 730:138324. [PMID: 32388385 DOI: 10.1016/j.scitotenv.2020.138324] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/23/2020] [Accepted: 03/28/2020] [Indexed: 06/11/2023]
Abstract
Plants are excellent climate indicators and their macro-remains or pollen accumulating in geological archives serve as recorders of environmental change. In Europe birch trees contribute importantly to Holocene plant successions. They constitute the dwarf species Betula nana and B. humilis, representing colder and two tree birches, B. pubescens and B. pendula indicative of more temperate climate. Birch pollen is highly similar preventing species differentiation. We obtained unambiguous chemotaxonomic differentiation of four European birch species via cuticular wax lipids. Dominating lipid classes in recent epicuticular birch waxes were n-alkanes (nC23 to nC33), n-alcohols and n-alkanoic acids (nC20 to nC32), and long-chain wax ester (nC36 to nC48) differing in amount and distribution. After plant senescence and in geological archives lipids undergo diagenetic alteration modifying the distributions found in recent plants. Long-chain wax esters via hydrolysis release bound n-alcohols and n-fatty acids, adding to their free analogues. Simulated release of bound lipids increased the pool of n-alcohol and n-fatty acids up to 400%. Such modification of primary lipid patterns is unaccounted for in most paleovegetation studies. Proceeding diagenesis, e.g. by decarboxylation will convert these functionalized primary and secondary lipids into their corresponding n-alkanes, the compound class mostly applied in paleoenvironment reconstruction. The simulated n-alkane pattern changed significantly, evidenced by an increase of mid-chain (nC23,nC25) homologues. Release of bound lipids may not only alter molecular but also isotopic composition, which may cause errors in paleoclimate reconstruction. We assessed the potential contribution of secondary (free lipid decarboxylation) and tertiary (bound lipid decarboxylation) wax metabolites and compared the cumulative n-alkane patterns with birch n-alkane distributions reported in the literature. Two statistically different patterns were separated, one dominated by primary, the other by secondary and tertiary formed n-alkanes. This may explain the inconsistency in previous birch wax analysis reported and needs consideration in paleoenvironment reconstruction.
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Affiliation(s)
- Jan Weber
- Department of Organic Geochemistry, Christian-Albrechts-University, Kiel, Germany
| | - Lorenz Schwark
- Department of Organic Geochemistry, Christian-Albrechts-University, Kiel, Germany; Department of Earth Sciences, WA-OIGC, Curtin University, Perth, Australia.
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Rowe CA, Lichvar RW, Wolf PG. How Many Tree Species of Birch Are in Alaska? Implications for Wetland Designations. FRONTIERS IN PLANT SCIENCE 2020; 11:750. [PMID: 32595670 PMCID: PMC7300271 DOI: 10.3389/fpls.2020.00750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
Wetland areas are critical habitats, especially in northern regions of North America. Wetland classifications are based on several factors, including the presence of certain plant species and assemblages of species, of which trees play a significant role. Here we examined wetland species of birch (Betula) in North America, with a focus on Alaska, and the use of birche tree species in wetland delineation. We sampled over 200 trees from sites, including Alaska, Alberta, Minnesota, and New Hampshire. We used genetic data from over 3000 loci detected by restriction site associated DNA analysis. We used an indirect estimate of ploidy based on allelic ratios and we also examined population genetic structure. We find that inferred ploidy is strongly associated with genetic groupings. We find two main distinct groups; one found throughout most of Alaska, extending into Alberta. This group is probably attributable to Betula kenaica, Betula neoalaskana, or both. This group has a diploid genetic pattern although this could easily be a function of allopolyploidy. The second major genetic group appears to extend from Eastern North America into parts of southeastern Alaska. This group represents Betula papyrifera, and is not diploid based on allelic ratios. Published chromosome counts indicate pentaploidy. Because B. papyrifera is the only one of the above species that is distinctly associated with wetland habitats, our findings indicate that tree species of birch found in most parts of Alaska are not reliable indicators of wetland habitats. These results help to support stronger wetland ratings assigned to the tree species of birch for delineation purposes.
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Affiliation(s)
- Carol A. Rowe
- Department of Biology, Utah State University, Logan, UT, United States
| | - Robert W. Lichvar
- United States Army Corps of Engineers, Cold Region Research and Engineering Laboratory, Hanover, NH, United States
| | - Paul G. Wolf
- Department of Biology, Utah State University, Logan, UT, United States
- Department of Biological Sciences, The University of Alabama in Huntsville, Huntsville, AL, United States
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Williams JH, Oliveira PE. For things to stay the same, things must change: polyploidy and pollen tube growth rates. ANNALS OF BOTANY 2020; 125:925-935. [PMID: 31957784 PMCID: PMC7218811 DOI: 10.1093/aob/mcaa007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 01/17/2020] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND AIMS Pollen tube growth rate (PTGR) is an important single-cell performance trait that may evolve rapidly under haploid selection. Angiosperms have experienced repeated cycles of polyploidy (whole genome duplication), and polyploidy has cell-level phenotypic consequences arising from increased bulk DNA amount and numbers of genes and their interactions. We sought to understand potential effects of polyploidy on several underlying determinants of PTGR - pollen tube dimensions and construction rates - by comparing diploid-polyploid near-relatives in Betula (Betulaceae) and Handroanthus (Bignoniaceae). METHODS We performed intraspecific, outcrossed hand-pollinations on pairs of flowers. In one flower, PTGR was calculated from the longest pollen tube per time of tube elongation. In the other, styles were embedded in glycol methacrylate, serial-sectioned in transverse orientation, stained and viewed at 1000× to measure tube wall thicknesses (W) and circumferences (C). Volumetric growth rate (VGR) and wall production rate (WPR) were then calculated for each tube by multiplying cross-sectional tube area (πr2) or wall area (W × C), by the mean PTGR of each maternal replicate respectively. KEY RESULTS In Betula and Handroanthus, the hexaploid species had significantly wider pollen tubes (13 and 25 %, respectively) and significantly higher WPRs (22 and 18 %, respectively) than their diploid congeners. PTGRs were not significantly different in both pairs, even though wider polyploid tubes were predicted to decrease PTGRs by 16 and 20 %, respectively. CONCLUSIONS The larger tube sizes of polyploids imposed a substantial materials cost on PTGR, but polyploids also exhibited higher VGRs and WPRs, probably reflecting the evolution of increased metabolic activity. Recurrent cycles of polyploidy followed by genome reorganization may have been important for the evolution of fast PTGRs in angiosperms, involving a complex interplay between correlated changes in ploidy level, genome size, cell size and pollen tube energetics.
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Affiliation(s)
- Joseph H Williams
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, USA
| | - Paulo E Oliveira
- Instituto de Biologia, Universidade Federal de Uberlândia, Campus Umuarama, Uberlândia, Minas Gerais 38405-320 Brazil
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Shuryak I. Review of resistance to chronic ionizing radiation exposure under environmental conditions in multicellular organisms. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2020; 212:106128. [PMID: 31818732 DOI: 10.1016/j.jenvrad.2019.106128] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/02/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
Ionizing radiation resistance occurs among many phylogenetic groups and its mechanisms remain incompletely understood. Tolerances to acute and chronic irradiation do not always correlate because different mechanisms may be involved. The radioresistance phenomenon becomes even more complex in the field than in the laboratory because the effects of radioactive contamination on natural populations are intertwined with those of other factors, such as bioaccumulation of radionuclides, interspecific competition, seasonal variations in environmental conditions, and land use changes due to evacuation of humans from contaminated areas. Previous reviews of studies performed in radioactive sites like the Kyshtym, Chernobyl, and Fukushima accident regions, and of protracted irradiation experiments, often focused on detecting radiation effects at low doses in radiosensitive organisms. Here we review the literature with a different purpose: to identify organisms with high tolerance to chronic irradiation under environmental conditions, which maintained abundant populations and/or outcompeted more radiosensitive species at high dose rates. Taxa for which consistent evidence for radioresistance came from multiple studies conducted in different locations and at different times were found among plants (e.g. willow and birch trees, sedges), invertebrate and vertebrate animals (e.g. rotifers, some insects, crustaceans and freshwater fish). These organisms are not specialized "extremophiles", but tend to tolerate broad ranges of environmental conditions and stresses, have small genomes, reproduce quickly and/or disperse effectively over long distances. Based on these findings, resistance to radioactive contamination can be examined in a more broad context of chronic stress responses.
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Affiliation(s)
- Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, 630 West 168th Street, VC-11-234/5, New York, NY, USA.
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Helmstetter AJ, Buggs RJA, Lucas SJ. Repeated long-distance dispersal and convergent evolution in hazel. Sci Rep 2019; 9:16016. [PMID: 31690762 PMCID: PMC6831691 DOI: 10.1038/s41598-019-52403-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 10/12/2019] [Indexed: 01/18/2023] Open
Abstract
Closely related species with a worldwide distribution provide an opportunity to understand evolutionary and biogeographic processes at a global scale. Hazel (Corylus) is an economically important genus of tree and shrub species found in temperate regions of Asia, North America and Europe. Here we use multiple nuclear and chloroplast loci to estimate a time-calibrated phylogenetic tree of the genus Corylus. We model the biogeographic history of this group and the evolutionary history of tree and shrub form. We estimate that multiple Corylus lineages dispersed long distances between Europe and Asia and colonised North America from Asia in multiple independent events. The geographic distribution of tree versus shrub form of species appears to be the result of 4–5 instances of convergent evolution in the past 25 million years. We find extensive discordance between our nuclear and chloroplast trees and potential evidence for chloroplast capture in species with overlapping ranges, suggestive of past introgression. The important crop species C. avellana is estimated to be closely related to C. maxima, C. heterophylla var. thunbergii and the Colurnae subsection. Our study provides a new phylogenetic hypothesis or Corylus and reveals how long-distance dispersal can shape the distribution of biodiversity in temperate plants.
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Affiliation(s)
- Andrew J Helmstetter
- Jodrell Laboratory, Royal Botanic Gardens, Kew, TW9 3AB, Richmond, UK. .,Institut de Recherche pour le Développement (IRD), UMR-DIADE, BP 64501, 34394, Montpellier, France.
| | - Richard J A Buggs
- Jodrell Laboratory, Royal Botanic Gardens, Kew, TW9 3AB, Richmond, UK.,School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Stuart J Lucas
- Sabanci University Nanotechnology Research and Application Center (SUNUM), Sabanci University, Orhanlı, 34956, Tuzla, Istanbul, Turkey
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Kuneš I, Linda R, Fér T, Karlík P, Baláš M, Ešnerová J, Vítámvás J, Bílý J, Urfus T. Is Betula carpatica genetically distinctive? A morphometric, cytometric and molecular study of birches in the Bohemian Massif with a focus on Carpathian birch. PLoS One 2019; 14:e0224387. [PMID: 31671142 PMCID: PMC6822711 DOI: 10.1371/journal.pone.0224387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 10/11/2019] [Indexed: 11/19/2022] Open
Abstract
Until recently, Czech taxonomists often treated Betula carpatica as a distinct species. Several morphological traits for distinguishing B. carpatica from B. pubescens or other birches are described in literature; however, it has been proven impossible to reliably identify B. carpatica in the field. With the use of morphological and molecular approaches, we intended to assess the position of B. carpatica in the context of other birch taxa reported from the Bohemian Massif and to find more reliable morphological traits for their identification. In our dataset, we distinguished the following birch taxa referred to in the recent Czech literature: B. pendula, B. pubescens, B. carpatica, B. oycoviensis, B. nana, B. petraea and B. ×seideliana. We complemented them with triploids and several diploid and tetraploid "working units" into which we included intermediate individuals that in terms of morphology did not unambiguously match any of the abovementioned birch taxa. Holoploid genome size was measured to determine the ploidy level. To identify genetic relationships between selected taxa and "working units", microsatellite analyses were performed. Model-based STRUCTURE analysis together with principal coordinates analysis (PCoA) based on genetic distances was performed to identify the similarities in multilocus genotype data between groups distinguished in the dataset. The applied analyses were not able clearly to distinguish any group among tetraploid individuals. In this light, it was of no use to search for any more reliable morphological traits of B. carpatica and also B. petraea. Among diploids, B. nana was always distinguished, in contrast to B. oycoviensis, which was not genetically recognized despite being usually morphologically distinct. Based on our results and a literature review, we suggest that B. carpatica and also the closely similar B. petraea should not be considered separate species. A similar conclusion seems relevant also for B. oycoviensis; however, further verification is desirable in this case.
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Affiliation(s)
- Ivan Kuneš
- Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Rostislav Linda
- Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Tomáš Fér
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Petr Karlík
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Martin Baláš
- Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Jana Ešnerová
- Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Jan Vítámvás
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Jan Bílý
- EXTEMIT-K, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic
| | - Tomáš Urfus
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
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Yin M, Guo J, Zeng J. Complete chloroplast genome sequence of Betula alnoides (Betulaceae). MITOCHONDRIAL DNA PART B-RESOURCES 2019; 4:2409-2410. [PMID: 33365566 PMCID: PMC7687603 DOI: 10.1080/23802359.2019.1637790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Betula alnoides (Betulaceae) is a species widely distributed in north tropical and warm subtropical zones in South-East Asia and southern China. In this study, we described the complete chloroplast genome of B. alnoides based on Illumina paired-end sequencing. The chloroplast genome of B. alnoides is 160,990 bp long, including two inverted repeats (IRs, 26,022 bp), separated by a large single-copy region (LSC, 89,719 bp) and a small single-copy region (SSC, 19,227 bp). The genome contains 113 genes, including 79 protein-codon genes (PCGs), four rRNA genes, and 30 tRNA genes. The overall GC content of the chloroplast genome was 35.9%. Phylogenetic analysis demonstrated that B. alnoides of Sect. Betulaster (Spach) Regel was quite different from species of Sect. Betula.
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Affiliation(s)
- Mingyu Yin
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, P.R. China
| | - Junjie Guo
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, P.R. China
| | - Jie Zeng
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, P.R. China
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Hu YN, Zhao L, Buggs RJA, Zhang XM, Li J, Wang N. Population structure of Betula albosinensis and Betula platyphylla: evidence for hybridization and a cryptic lineage. ANNALS OF BOTANY 2019; 123:1179-1189. [PMID: 30916314 PMCID: PMC6612935 DOI: 10.1093/aob/mcz024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 01/15/2019] [Accepted: 02/05/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND AND AIMS Differences in local abundance and ploidy level are predicted to impact the direction of introgression between species. Here, we tested these hypotheses on populations of Betula albosinensis (red birch) and Betula platyphylla (white birch) which were thought to differ in ploidy level, the former being tetraploid and the latter diploid. METHODS We sampled 391 birch individuals from nine localities in China, and classified them into species based on leaf morphology. Twelve nuclear microsatellite markers were genotyped in each sample, and analysed using principal coordinates analysis and STRUCTURE software. We compared the effects of two different methods of scoring polyploid genotypes on population genetic analyses. We analysed the effect of ploidy, local species abundance and latitude on levels of introgression between the species. KEY RESULTS Leaf morphology divided our samples into red and white birch, but genetic analyses unexpectedly revealed two groups within red birch, one of which was tetraploid, as expected, but the other of which appeared to have diploid microsatellite genotypes. Five individuals were identified as early-generation hybrids or backcrosses between white birch and red birch and five were identified between red birch and 'diploid' red birch. Cline analysis showed that levels of admixture were not significantly correlated with latitude. Estimated genetic differentiation among species was not significantly different between determined tetraploid and undetermined tetraploid genotypes. CONCLUSIONS Limited hybridization and gene flow have occurred between red birch and white birch. Relative species abundance and ploidy level do not impact the direction of introgression between them, as genetic admixture is roughly symmetrical. We unexpectedly found populations of apparently diploid red birch and this taxon may be a progenitor of allotetraploid red birch populations. Incomplete lineage sorting may explain patterns of genetic admixture between apparently diploid and allotetraploid red birch.
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Affiliation(s)
- Ya-Nan Hu
- College of Forestry, Shandong Agricultural University, Tai’an city, Shandong province, China
| | - Lei Zhao
- Beijing Key Laboratory of Biodiversity and Organic Farming, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Richard J A Buggs
- Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Xue-Min Zhang
- Mulan-Weichang National Forestry Administration, Chengde, China
| | - Jun Li
- Mulan-Weichang National Forestry Administration, Chengde, China
| | - Nian Wang
- College of Forestry, Shandong Agricultural University, Tai’an city, Shandong province, China
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Rewicz A, Rewers M, Jędrzejczyk I, Rewicz T, Kołodziejek J, Jakubska-Busse A. Morphology and genome size of Epipactis helleborine (L.) Crantz (Orchidaceae) growing in anthropogenic and natural habitats. PeerJ 2018; 6:e5992. [PMID: 30595975 PMCID: PMC6304265 DOI: 10.7717/peerj.5992] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 10/23/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The process of apophytism or spreading native species to human-made habitats is one of the main elements in the creation of plant cover in anthropogenic areas. Lately, an increase of anthropogenic localities with valuable flora has been observed. Apophytes are also members of the family Orchidaceae, especially from the genus Epipactis. The aim of the study was to (i) determine and compare the phenotypic variation of E. helleborine (L.) Crantz plants in anthropogenic and natural habitats, (ii) compare the genome size of plants growing in natural and anthropogenic habitats. The results reported in this study may indicate that a habitat influences morphological characteristics of plant species. METHODS Field studies were conducted on four native stands and four stands in anthropogenic areas of E. helleborine in Poland in years 2011-2013. Biometrical analyses were performed on shoots and flowers. The flowers were characterised by 25 biometric features and measured using a Nikon SMZ 800 binocular, microscopic Moticam-1SP cameras and the MIPlus07 programme (Conbest Co.). The nuclear DNA content was determined in fresh and young leaves of E. helleborine, collected from four natural and four anthropogenic populations. RESULTS We observed that in anthropogenic populations: (i) shoots were higher than shoots from natural populations, (ii) flowers differed significantly in terms of ten biometric features between habitats, (iii) the genome size of some population differed significantly between plants growing in natural and anthropogenic habitats. DISCUSSION According to some researchers, the presence of phenotypic variability and the occurrence of ecotypes are adaptation strategies of plants to environmental changes. In our opinion, in the case of the studied anthropogenic habitats (roadside) in which the E. helleborine populations grew, we can talk about ecofen due to the often repeated set of characteristic features, i.e., high shoots, long inflorescence and long, broad leaves. We agree, however, that it is difficult to isolate a taxonomic unit for ecofen due to the lack of experimental research.
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Affiliation(s)
- Agnieszka Rewicz
- Department of Geobotany and Plant Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Łódź, Poland
| | - Monika Rewers
- Department of Agricultural Biotechnology, UTP University of Science and Technology, Laboratory of Molecular Biology and Cytometry, Bydgoszcz, Poland
| | - Iwona Jędrzejczyk
- Department of Agricultural Biotechnology, UTP University of Science and Technology, Laboratory of Molecular Biology and Cytometry, Bydgoszcz, Poland
| | - Tomasz Rewicz
- Department of Invertebrate Zoology and Hydrobiology, Faculty of Biology and Environmental Protection, University of Lodz, Łódź, Poland
| | - Jeremi Kołodziejek
- Department of Geobotany and Plant Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Łódź, Poland
| | - Anna Jakubska-Busse
- Department of Botany, Institute of Environmental Biology, University of Wrocław, Wrocław, Poland
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Characterization of chloroplast genomes of Alnus rubra and Betula cordifolia, and their use in phylogenetic analyses in Betulaceae. Genes Genomics 2018; 41:305-316. [PMID: 30456523 DOI: 10.1007/s13258-018-0762-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 11/04/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE Betulaceae is a relatively small birch family that comprises about 160 deciduous trees and shrubs. Chloroplast (cp) genome sequencing of Alnus rubra and Betula cordifolia was carried out to elucidate their molecular features and phylogenetic relationship among species in Betulaceae family. METHODS Chloroplast genome sequencing was carried out using next generation sequencing method. Molecular and genomic features of the two cp genomes were characterized with other cp genomes in Betulaceae. Also, molecular phylogenetic analysis was performed using the whole cp genome sequences. RESULTS The average cp genome length was 160,136 bp among the Betulaceae species. Base compositions of the cp genomes were skewed toward a high AT ratio, with an average of 63.4%. We identified 117 different genes 83 with protein coding, 4 with ribosomal RNA, and 30 with tRNA. Eighteen genes contained introns which were conserved among the cp genomes of all Betulaceae. We mined 82 SSRs from the cp genomes of A. rubra, A. cordifolia, and A. nana. The SSRs were variable in motif repeat numbers and presence/absence among the cp genomes. CONCLUSION Chloroplast genome-wide sequence comparison from 11 Betulaceae species and one cp genome of evergreen oak revealed that the patterns of sequence variations were congruent with two subfamily classification Betuloideae (Alnus and Betula) and Corylaceae (Corylus, Ostrya, and Carpinus). Subsequent phylogenetic analysis also supports the sub-classifications of these species.
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Tan J, Guo JJ, Yin MY, Wang H, Dong WP, Zeng J, Zhou SL. Next Generation Sequencing-Based Molecular Marker Development: A Case Study in Betula Alnoides. Molecules 2018; 23:E2963. [PMID: 30428601 PMCID: PMC6278481 DOI: 10.3390/molecules23112963] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/09/2018] [Accepted: 11/11/2018] [Indexed: 11/25/2022] Open
Abstract
Betula alnoides is a fast-growing valuable indigenous tree species with multiple uses in the tropical and warm subtropical regions in South-East Asia and southern China. It has been proved to be tetraploid in most parts of its distribution in China. In the present study, next generation sequencing (NGS) technology was applied to develop numerous SSR markers for B. alnoides, and 64,376 contig sequences of 106,452 clean reads containing 164,357 candidate SSR loci were obtained. Among the derived SSR repeats, mono-nucleotide was the main type (77.05%), followed by di- (10.18%), tetra- (6.12%), tri- (3.56%), penta- (2.14%) and hexa-nucleotide (0.95%). The short nucleotide sequence repeats accounted for 90.79%. Among the 291 repeat motifs, AG/CT (46.33%) and AT/AT (44.15%) were the most common di-nucleotide repeats, while AAT/ATT (48.98%) was the most common tri-nucleotide repeats. A total of 2549 primer sets were designed from the identified putative SSR regions of which 900 were randomly selected for evaluation of amplification successfulness and detection of polymorphism if amplified successfully. Three hundred and ten polymorphic markers were obtained through testing with 24 individuals from B. alnoides natural forest in Jingxi County, Guangxi, China. The number of alleles (NA) of each marker ranged from 2 to 19 with a mean of 5.14. The observed (HO) and expected (HE) heterozygosities varied from 0.04 to 1.00 and 0.04 to 0.92 with their means being 0.64 and 0.57, respectively. Shannon-Wiener diversity index (I) ranged from 0.10 to 2.68 with a mean of 1.12. Cross-species transferability was further examined for 96 pairs of SSR primers randomly selected, and it was found that 48.96⁻84.38% of the primer pairs could successfully amplify each of six related Betula species. The obtained SSR markers can be used to study population genetics and molecular marker assisted breeding, particularly genome-wide association study of these species in the future.
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Affiliation(s)
- Jing Tan
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China.
| | - Jun-Jie Guo
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China.
| | - Ming-Yu Yin
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China.
| | - Huan Wang
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China.
| | - Wen-Pan Dong
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
| | - Jie Zeng
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China.
| | - Shi-Liang Zhou
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
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Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch. Nat Genet 2017; 49:904-912. [PMID: 28481341 DOI: 10.1038/ng.3862] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 04/12/2017] [Indexed: 12/26/2022]
Abstract
Silver birch (Betula pendula) is a pioneer boreal tree that can be induced to flower within 1 year. Its rapid life cycle, small (440-Mb) genome, and advanced germplasm resources make birch an attractive model for forest biotechnology. We assembled and chromosomally anchored the nuclear genome of an inbred B. pendula individual. Gene duplicates from the paleohexaploid event were enriched for transcriptional regulation, whereas tandem duplicates were overrepresented by environmental responses. Population resequencing of 80 individuals showed effective population size crashes at major points of climatic upheaval. Selective sweeps were enriched among polyploid duplicates encoding key developmental and physiological triggering functions, suggesting that local adaptation has tuned the timing of and cross-talk between fundamental plant processes. Variation around the tightly-linked light response genes PHYC and FRS10 correlated with latitude and longitude and temperature, and with precipitation for PHYC. Similar associations characterized the growth-promoting cytokinin response regulator ARR1, and the wood development genes KAK and MED5A.
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Igarashi Y, Aihara H, Handa Y, Katsumata H, Fujii M, Nakano K, Hirao T. Development and evaluation of microsatellite markers for the critically endangered birch Betula chichibuensis (Betulaceae). APPLICATIONS IN PLANT SCIENCES 2017; 5:apps1700016. [PMID: 28529833 PMCID: PMC5435406 DOI: 10.3732/apps.1700016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 03/30/2017] [Indexed: 06/07/2023]
Abstract
PREMISE OF THE STUDY Microsatellite markers were developed and characterized for the critically endangered birch Betula chichibuensis (Betulaceae) to investigate the genetic structure of this species for conservation purposes. METHODS AND RESULTS Sixteen microsatellite markers with di-, tri-, and tetranucleotide repeat motifs were developed and optimized using MiSeq paired-end sequencing. Of these, 14 were polymorphic, with two to five alleles per locus, in 47 individuals from two newly discovered populations of B. chichibuensis in Japan. Observed and unbiased expected heterozygosities per locus ranged from 0.000 to 0.617 and from 0.000 to 0.629, respectively. These markers were tested for cross-species amplification in B. maximowicziana, B. platyphylla var. japonica, and B. schmidtii. CONCLUSIONS This set of microsatellite markers, the first developed for B. chichibuensis, will help elucidate spatial patterns of gene flow and levels of inbreeding in this species to aid its conservation.
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Affiliation(s)
- Yuji Igarashi
- The University of Tokyo Chichibu Forest, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-49 Hinoda-machi, Chichibu, Saitama 368-0034, Japan
| | - Hiroki Aihara
- FASMAC Co. Ltd., 5-1-3 Midorigaoka, Atsugi, Kanagawa 243-0041, Japan
| | - Yoshihiro Handa
- FASMAC Co. Ltd., 5-1-3 Midorigaoka, Atsugi, Kanagawa 243-0041, Japan
| | - Hiroshi Katsumata
- FASMAC Co. Ltd., 5-1-3 Midorigaoka, Atsugi, Kanagawa 243-0041, Japan
| | - Masanori Fujii
- Institute for Environmental Sciences, 1-7 Ienomae, Obuchi, Rokkasho, Kamikita, Aomori 039-3212, Japan
| | - Koichiro Nakano
- FASMAC Co. Ltd., 5-1-3 Midorigaoka, Atsugi, Kanagawa 243-0041, Japan
| | - Toshihide Hirao
- The University of Tokyo Chichibu Forest, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-49 Hinoda-machi, Chichibu, Saitama 368-0034, Japan
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Wang Y, Chen Q, Chen T, Tang H, Liu L, Wang X. Phylogenetic Insights into Chinese Rubus (Rosaceae) from Multiple Chloroplast and Nuclear DNAs. FRONTIERS IN PLANT SCIENCE 2016; 7:968. [PMID: 27446191 PMCID: PMC4925702 DOI: 10.3389/fpls.2016.00968] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 06/16/2016] [Indexed: 05/09/2023]
Abstract
Rubus L. is a large and taxonomically complex genus, species of which exhibit apomixis, polyploidy, and frequent hybridization. Most of Chinese Rubus are assigned in two major sections, Idaeobatus and Malachobatus. To explore the phylogenetic relationships within Chinese Rubus, inferences upon three chloroplast DNA (rbcL, rpl20-rps12, and trnG-trnS), nuclear ribosomal ITS, and two low-copy nuclear markers (GBSSI-2 and PEPC) were deduced in 142 Rubus taxa from 17 subsections in 6 sections. nrITS and GBSSI-2 were the most informative among the six DNA regions assessed. Phylogenetic relationships within Rubus were well-resolved by combined nuclear datasets rather than chloroplast markers. The phylogenetic inferences strongly supported that section Idaeobatus was a polyphyletic group with four distant clades. All samples of sect. Malachobatus formed a monophyletic clade, in which R. tsangorum and R. amphidasys of sect. Dalibardastrum, and R. peltatus from subsection Peltati of sect. Idaeobatus were always nested. Rubus pentagonus (2n = 2x = 14) from subsect. Alpestres of sect. Idaeobatus was a sister group to the polyploid sect. Malachobatus, as well as the polytomy of three sect. Cyalctis members. This suggests that some polyploids of Malachobatus might originate from common ancestors, via polyploidization of hybrids between R. pentagonus and sect. Cylactis species. They had experienced species explosion in a short time. Section Dalibardastrum species have potential parental lineages from subsects. Moluccani and Stipulosi of sect. Malachobatus. Based on molecular phylogenies, we also provided recommendations for the taxonomic treatments of four taxa. In addition, our results showed certain incongruence between chloroplast and nuclear markers, which might be due to hybridization and introgression.
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Affiliation(s)
- Yan Wang
- College of Horticulture, Sichuan Agricultural UniversityChengdu, China
| | - Qing Chen
- College of Horticulture, Sichuan Agricultural UniversityChengdu, China
| | - Tao Chen
- College of Horticulture, Sichuan Agricultural UniversityChengdu, China
| | - Haoru Tang
- College of Horticulture, Sichuan Agricultural UniversityChengdu, China
- Institute of Pomology and Olericulture, Sichuan Agricultural UniversityChengdu, China
| | - Lin Liu
- Agricultural and Animal Husbandry College of Tibet UniversityLinzhi, China
| | - Xiaorong Wang
- College of Horticulture, Sichuan Agricultural UniversityChengdu, China
- Institute of Pomology and Olericulture, Sichuan Agricultural UniversityChengdu, China
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Zohren J, Wang N, Kardailsky I, Borrell JS, Joecker A, Nichols RA, Buggs RJA. Unidirectional diploid-tetraploid introgression among British birch trees with shifting ranges shown by restriction site-associated markers. Mol Ecol 2016; 25:2413-26. [PMID: 27065091 PMCID: PMC4999052 DOI: 10.1111/mec.13644] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 04/05/2016] [Accepted: 04/08/2016] [Indexed: 01/02/2023]
Abstract
Hybridization may lead to introgression of genes among species. Introgression may be bidirectional or unidirectional, depending on factors such as the demography of the hybridizing species, or the nature of reproductive barriers between them. Previous microsatellite studies suggested bidirectional introgression between diploid Betula nana (dwarf birch) and tetraploid B. pubescens (downy birch) and also between B. pubescens and diploid B. pendula (silver birch) in Britain. Here, we analyse introgression among these species using 51 237 variants in restriction site‐associated (RAD) markers in 194 individuals, called with allele dosages in the tetraploids. In contrast to the microsatellite study, we found unidirectional introgression into B. pubescens from both of the diploid species. This pattern fits better with the expected nature of the reproductive barrier between diploids and tetraploids. As in the microsatellite study, introgression into B. pubescens showed clear clines with increasing introgression from B. nana in the north and from B. pendula in the south. Unlike B. pendula alleles, introgression of B. nana alleles was found far from the current area of sympatry or allopatry between B. nana and B. pubescens. This pattern fits a shifting zone of hybridization due to Holocene reduction in the range of B. nana and expansion in the range of B. pubescens.
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Affiliation(s)
- Jasmin Zohren
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Nian Wang
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Igor Kardailsky
- QIAGEN Aarhus A/S, Silkeborgvej 2, Prismet, Aarhus C, 8000, Denmark
| | - James S Borrell
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Anika Joecker
- QIAGEN Aarhus A/S, Silkeborgvej 2, Prismet, Aarhus C, 8000, Denmark
| | - Richard A Nichols
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Richard J A Buggs
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
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