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Bruxaux J, Zhao W, Hall D, Curtu AL, Androsiuk P, Drouzas AD, Gailing O, Konrad H, Sullivan AR, Semerikov V, Wang XR. Scots pine - panmixia and the elusive signal of genetic adaptation. THE NEW PHYTOLOGIST 2024; 243:1231-1246. [PMID: 38308133 DOI: 10.1111/nph.19563] [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: 11/15/2023] [Accepted: 01/14/2024] [Indexed: 02/04/2024]
Abstract
Scots pine is the foundation species of diverse forested ecosystems across Eurasia and displays remarkable ecological breadth, occurring in environments ranging from temperate rainforests to arid tundra margins. Such expansive distributions can be favored by various demographic and adaptive processes and the interactions between them. To understand the impact of neutral and selective forces on genetic structure in Scots pine, we conducted range-wide population genetic analyses on 2321 trees from 202 populations using genotyping-by-sequencing, reconstructed the recent demography of the species and examined signals of genetic adaptation. We found a high and uniform genetic diversity across the entire range (global FST 0.048), no increased genetic load in expanding populations and minor impact of the last glacial maximum on historical population sizes. Genetic-environmental associations identified only a handful of single-nucleotide polymorphisms significantly linked to environmental gradients. The results suggest that extensive gene flow is predominantly responsible for the observed genetic patterns in Scots pine. The apparent missing signal of genetic adaptation is likely attributed to the intricate genetic architecture controlling adaptation to multi-dimensional environments. The panmixia metapopulation of Scots pine offers a good study system for further exploration into how genetic adaptation and plasticity evolve under gene flow and changing environment.
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Affiliation(s)
- Jade Bruxaux
- Department of Ecology and Environmental Science, Umeå Plant Science Center, Umeå University, 901 87, Umeå, Sweden
| | - Wei Zhao
- Department of Ecology and Environmental Science, Umeå Plant Science Center, Umeå University, 901 87, Umeå, Sweden
| | - David Hall
- Department of Ecology and Environmental Science, Umeå Plant Science Center, Umeå University, 901 87, Umeå, Sweden
- Forestry Research Institute of Sweden (Skogforsk), 918 21, Sävar, Sweden
| | | | - Piotr Androsiuk
- Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719, Olsztyn, Poland
| | - Andreas D Drouzas
- Laboratory of Systematic Botany and Phytogeography, School of Biology, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Oliver Gailing
- Department of Forest Genetics and Forest Tree Breeding, University of Göttingen, 37077, Göttingen, Germany
| | - Heino Konrad
- Department of Forest Biodiversity and Nature Conservation, Unit of Ecological Genetics, Austrian Research Centre for Forests (BFW), 1140, Vienna, Austria
| | - Alexis R Sullivan
- Department of Ecology and Environmental Science, Umeå Plant Science Center, Umeå University, 901 87, Umeå, Sweden
| | - Vladimir Semerikov
- Institute of Plant and Animal Ecology, Ural Division of Russian Academy of Sciences, 620144, Ekaterinburg, Russia
| | - Xiao-Ru Wang
- Department of Ecology and Environmental Science, Umeå Plant Science Center, Umeå University, 901 87, Umeå, Sweden
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Zhang TT, Yan CL, Qiao JX, Yang AS, Liu ML, Kou YX, Li ZH. Demographic dynamics and molecular evolution of the rare and endangered subsect. Gerardianae of Pinus: insights from chloroplast genomes and mitochondrial DNA markers. PLANTA 2024; 259:45. [PMID: 38281265 DOI: 10.1007/s00425-023-04316-8] [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: 07/11/2023] [Accepted: 12/21/2023] [Indexed: 01/30/2024]
Abstract
MAIN CONCLUSION The divergence of subsect. Gerardianae was likely triggered by the uplift of the Qinghai-Tibetan Plateau and adjacent mountains. Pinus bungeana might have probably experienced expansion since Last Interglacial period. Historical geological and climatic oscillations have profoundly affected patterns of nucleotide variability, evolutionary history, and species divergence in numerous plants of the Northern Hemisphere. However, how long-lived conifers responded to geological and climatic fluctuations in East Asia remain poorly understood. Here, based on paternally inherited chloroplast genomes and maternally inherited mitochondrial DNA markers, we investigated the population demographic history and molecular evolution of subsect. Gerardianae (only including three species, Pinus bungeana, P. gerardiana, and P. squamata) of Pinus. A low level of nucleotide diversity was found in P. bungeana (π was 0.00016 in chloroplast DNA sequences, and 0.00304 in mitochondrial DNAs). The haplotype-based phylogenetic topology and unimodal distributions of demographic analysis suggested that P. bungeana probably originated in the southern Qinling Mountains and experienced rapid population expansion since Last Interglacial period. Phylogenetic analysis revealed that P. gerardiana and P. squamata had closer genetic relationship. The species divergence of subsect. Gerardianae occurred about 27.18 million years ago (Mya) during the middle to late Oligocene, which was significantly associated with the uplift of the Qinghai-Tibetan Plateau and adjacent mountains from the Eocene to the mid-Pliocene. The molecular evolutionary analysis showed that two chloroplast genes (psaI and ycf1) were under positive selection, the genetic lineages of P. bungeana exhibited higher transition and nonsynonymous mutations, which were involved with the strongly environmental adaptation. These findings shed light on the population evolutionary history of white pine species and provide striking insights for comprehension of their species divergence and molecular evolution.
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Affiliation(s)
- Ting-Ting Zhang
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Chun-Li Yan
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Jin-Xia Qiao
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Ao-Shuang Yang
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Mi-Li Liu
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Yi-Xuan Kou
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Zhong-Hu Li
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China.
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Cervantes S, Kesälahti R, Kumpula TA, Mattila TM, Helanterä H, Pyhäjärvi T. Strong Purifying Selection in Haploid Tissue-Specific Genes of Scots Pine Supports the Masking Theory. Mol Biol Evol 2023; 40:msad183. [PMID: 37565532 PMCID: PMC10457172 DOI: 10.1093/molbev/msad183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/16/2023] [Accepted: 08/10/2023] [Indexed: 08/12/2023] Open
Abstract
The masking theory states that genes expressed in a haploid stage will be under more efficient selection. In contrast, selection will be less efficient in genes expressed in a diploid stage, where the fitness effects of recessive deleterious or beneficial mutations can be hidden from selection in heterozygous form. This difference can influence several evolutionary processes such as the maintenance of genetic variation, adaptation rate, and genetic load. Masking theory expectations have been confirmed in single-cell haploid and diploid organisms. However, in multicellular organisms, such as plants, the effects of haploid selection are not clear-cut. In plants, the great majority of studies indicating haploid selection have been carried out using male haploid tissues in angiosperms. Hence, evidence in these systems is confounded with the effects of sexual selection and intraspecific competition. Evidence from other plant groups is scarce, and results show no support for the masking theory. Here, we have used a gymnosperm Scots pine megagametophyte, a maternally derived seed haploid tissue, and four diploid tissues to test the strength of purifying selection on a set of genes with tissue-specific expression. By using targeted resequencing data of those genes, we obtained estimates of genetic diversity, the site frequency spectrum of 0-fold and 4-fold sites, and inferred the distribution of fitness effects of new mutations in haploid and diploid tissue-specific genes. Our results show that purifying selection is stronger for tissue-specific genes expressed in the haploid megagametophyte tissue and that this signal of strong selection is not an artifact driven by high expression levels.
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Affiliation(s)
- Sandra Cervantes
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
- Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Robert Kesälahti
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
| | - Timo A Kumpula
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Laboratory of Cancer Genetics and Tumor Biology, Research Unit of Translational Medicine, University of Oulu, Oulu, Finland
| | - Tiina M Mattila
- Human Evolution, Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | - Heikki Helanterä
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
| | - Tanja Pyhäjärvi
- Department of Forest Sciences, University of Helsinki, Helsinki, Finland
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García-García I, Méndez-Cea B, González de Andrés E, Gazol A, Sánchez-Salguero R, Manso-Martínez D, Horreo JL, Camarero JJ, Linares JC, Gallego FJ. Climate and Soil Microsite Conditions Determine Local Adaptation in Declining Silver Fir Forests. PLANTS (BASEL, SWITZERLAND) 2023; 12:2607. [PMID: 37514222 PMCID: PMC10384727 DOI: 10.3390/plants12142607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/15/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023]
Abstract
Ongoing climatic change is threatening the survival of drought-sensitive tree species, such as silver fir (Abies alba). Drought-induced dieback had been previously explored in this conifer, although the role played by tree-level genetic diversity and its relationship with growth patterns and soil microsite conditions remained elusive. We used double digest restriction-site-associated DNA sequencing (ddRADseq) to describe different genetic characteristics of five silver fir forests in the Spanish Pyrenees, including declining and non-declining trees. Single nucleotide polymorphisms (SNPs) were used to investigate the relationships between genetics, dieback, intraspecific trait variation (functional dendrophenotypic traits and leaf traits), local bioclimatic conditions, and rhizosphere soil properties. While there were no noticeable genetic differences between declining and non-declining trees, genome-environment associations with selection signatures were abundant, suggesting a strong influence of climate, soil physicochemical properties, and soil microbial diversity on local adaptation. These results provide novel insights into how genetics and diverse environmental factors are interrelated and highlight the need to incorporate genetic data into silver fir forest dieback studies to gain a better understanding of local adaptation.
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Affiliation(s)
- Isabel García-García
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Belén Méndez-Cea
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | | | - Antonio Gazol
- Instituto Pirenaico de Ecología (IPE-CSIC), 50059 Zaragoza, Spain
| | - Raúl Sánchez-Salguero
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
| | - David Manso-Martínez
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Jose Luis Horreo
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J Julio Camarero
- Instituto Pirenaico de Ecología (IPE-CSIC), 50059 Zaragoza, Spain
| | - Juan Carlos Linares
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
| | - Francisco Javier Gallego
- Departamento de Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
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Guo JF, Zhao W, Andersson B, Mao JF, Wang XR. Genomic clines across the species boundary between a hybrid pine and its progenitor in the eastern Tibetan Plateau. PLANT COMMUNICATIONS 2023:100574. [PMID: 36906801 PMCID: PMC10363505 DOI: 10.1016/j.xplc.2023.100574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 02/09/2023] [Accepted: 03/08/2023] [Indexed: 06/18/2023]
Abstract
Most species have clearly defined distribution ranges and ecological niches. The genetic and ecological causes of species differentiation and the mechanisms that maintain species boundaries between newly evolved taxa and their progenitors are, however, less clearly defined. This study investigated the genetic structure and clines in Pinus densata, a pine of hybrid origin on the southeastern Tibetan Plateau, to gain an understanding of the contemporary dynamics of species barriers. We analyzed genetic diversity in a range-wide collection of P. densata and representative populations of its progenitors, Pinus tabuliformis and Pinus yunnanensis, using exome capture sequencing. We detected four distinct genetic groups within P. densata that reflect its migration history and major gene-flow barriers across the landscape. The demographies of these genetic groups in the Pleistocene were associated with regional glaciation histories. Interestingly, population sizes rebounded rapidly during interglacial periods, suggesting persistence and resilience of the species during the Quaternary ice age. In the contact zone between P. densata and P. yunnanensis, 3.36% of the analyzed loci (57 849) showed exceptional patterns of introgression, suggesting their potential roles in either adaptive introgression or reproductive isolation. These outliers showed strong clines along critical climate gradients and enrichment in a number of biological processes relevant to high-altitude adaptation. This indicates that ecological selection played an important role in generating genomic heterogeneity and a genetic barrier across a zone of species transition. Our study highlights the forces that operate to maintain species boundaries and promote speciation in the Qinghai-Tibetan Plateau and other mountain systems.
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Affiliation(s)
- Jing-Fang Guo
- National Engineering Research Center of Tree Breeding and Ecological Restoration; State Key Laboratory of Tree Genetics and Breeding; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Wei Zhao
- Department of Ecology and Environmental Science, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden
| | - Bea Andersson
- Department of Ecology and Environmental Science, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden
| | - Jian-Feng Mao
- National Engineering Research Center of Tree Breeding and Ecological Restoration; State Key Laboratory of Tree Genetics and Breeding; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Xiao-Ru Wang
- Department of Ecology and Environmental Science, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden.
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6
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Kastally C, Niskanen AK, Perry A, Kujala ST, Avia K, Cervantes S, Haapanen M, Kesälahti R, Kumpula TA, Mattila TM, Ojeda DI, Tyrmi JS, Wachowiak W, Cavers S, Kärkkäinen K, Savolainen O, Pyhäjärvi T. Taming the massive genome of Scots pine with PiSy50k, a new genotyping array for conifer research. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:1337-1350. [PMID: 34897859 PMCID: PMC9303803 DOI: 10.1111/tpj.15628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 11/05/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
Pinus sylvestris (Scots pine) is the most widespread coniferous tree in the boreal forests of Eurasia, with major economic and ecological importance. However, its large and repetitive genome presents a challenge for conducting genome-wide analyses such as association studies, genetic mapping and genomic selection. We present a new 50K single-nucleotide polymorphism (SNP) genotyping array for Scots pine research, breeding and other applications. To select the SNP set, we first genotyped 480 Scots pine samples on a 407 540 SNP screening array and identified 47 712 high-quality SNPs for the final array (called 'PiSy50k'). Here, we provide details of the design and testing, as well as allele frequency estimates from the discovery panel, functional annotation, tissue-specific expression patterns and expression level information for the SNPs or corresponding genes, when available. We validated the performance of the PiSy50k array using samples from Finland and Scotland. Overall, 39 678 (83.2%) SNPs showed low error rates (mean = 0.9%). Relatedness estimates based on array genotypes were consistent with the expected pedigrees, and the level of Mendelian error was negligible. In addition, array genotypes successfully discriminate between Scots pine populations of Finnish and Scottish origins. The PiSy50k SNP array will be a valuable tool for a wide variety of future genetic studies and forestry applications.
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Affiliation(s)
- Chedly Kastally
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Alina K. Niskanen
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Annika Perry
- UK Centre for Ecology & HydrologyBush EstatePenicuikMidlothianEH26 0QBUK
| | - Sonja T. Kujala
- Natural Resources Institute Finland (Luke)Paavo Havaksen tie 390570OuluFinland
| | - Komlan Avia
- Université de StrasbourgINRAESVQV UMR‐A 1131F‐68000ColmarFrance
| | - Sandra Cervantes
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Matti Haapanen
- Natural Resources Institute Finland (Luke)Latokartanonkaari 9FI‐00790HelsinkiFinland
| | - Robert Kesälahti
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Timo A. Kumpula
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Tiina M. Mattila
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
- Department of Organismal BiologyEBCUppsala UniversityNorbyvägen 18 AUppsala752 36Sweden
| | - Dario I. Ojeda
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
- Norwegian Institute of Bioeconomy ResearchP.O. Box 115Ås1431Norway
| | - Jaakko S. Tyrmi
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Witold Wachowiak
- Institute of Environmental BiologyFaculty of BiologyAdam Mickiewicz University in PoznańUniwersytetu Poznańskiego 661‐614PoznańPoland
| | - Stephen Cavers
- UK Centre for Ecology & HydrologyBush EstatePenicuikMidlothianEH26 0QBUK
| | - Katri Kärkkäinen
- Natural Resources Institute Finland (Luke)Paavo Havaksen tie 390570OuluFinland
| | - Outi Savolainen
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
| | - Tanja Pyhäjärvi
- Department of Ecology and GeneticsUniversity of OuluP.O. Box 300090014OuluFinland
- Department of Forest SciencesUniversity of HelsinkiP.O. Box 2700014HelsinkiFinland
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7
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A transcriptome-based association study of growth, wood quality, and oleoresin traits in a slash pine breeding population. PLoS Genet 2022; 18:e1010017. [PMID: 35108269 PMCID: PMC8843129 DOI: 10.1371/journal.pgen.1010017] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 02/14/2022] [Accepted: 01/04/2022] [Indexed: 12/04/2022] Open
Abstract
Slash pine (Pinus elliottii Engelm.) is an important timber and resin species in the United States, China, Brazil and other countries. Understanding the genetic basis of these traits will accelerate its breeding progress. We carried out a genome-wide association study (GWAS), transcriptome-wide association study (TWAS) and weighted gene co-expression network analysis (WGCNA) for growth, wood quality, and oleoresin traits using 240 unrelated individuals from a Chinese slash pine breeding population. We developed high quality 53,229 single nucleotide polymorphisms (SNPs). Our analysis reveals three main results: (1) the Chinese breeding population can be divided into three genetic groups with a mean inbreeding coefficient of 0.137; (2) 32 SNPs significantly were associated with growth and oleoresin traits, accounting for the phenotypic variance ranging from 12.3% to 21.8% and from 10.6% to 16.7%, respectively; and (3) six genes encoding PeTLP, PeAP2/ERF, PePUP9, PeSLP, PeHSP, and PeOCT1 proteins were identified and validated by quantitative real time polymerase chain reaction for their association with growth and oleoresin traits. These results could be useful for tree breeding and functional studies in advanced slash pine breeding program. Slash pine is an important source of original timber and resin production on commercial forest plantations. It is necessary to implement precise breeding strategies to improve timber quality and resin yield. However, little is known about the species’ molecular genetic basis. Using a transcriptome dataset with sequencing from 240 individuals in the slash pine population, we combined multiple approaches (based on gene variation, expression variation and co-expression network) to dissect the genetic structure for slash pine major breeding traits. We found that the research population could be divided into three genetic groups with a mean heterozygosity of 0.2246. We also found that six genes with important functions in slash pine resin synthesis and timber formation through association studies. Four new SNPs associatation with the average ring width were also discovered. Our results provide new insights into the molecular genetic basis of important traits in slash pine and provide a comprehensive method for association analyses of conifer tree species with large genome.
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8
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Marek S, Tomaszewski D, Żytkowiak R, Jasińska A, Zadworny M, Boratyńska K, Dering M, Danusevičius D, Oleksyn J, Wyka TP. Stomatal density in Pinus sylvestris as an indicator of temperature rather than CO 2 : Evidence from a pan-European transect. PLANT, CELL & ENVIRONMENT 2022; 45:121-132. [PMID: 34748220 DOI: 10.1111/pce.14220] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/13/2021] [Accepted: 10/28/2021] [Indexed: 05/15/2023]
Abstract
The commonly observed negative relationship between stomatal density (SD) and atmospheric CO2 has led to SD being proposed as an indicator of atmospheric CO2 concentration. The use of SD as a proxy for CO2 , however, has been hampered by an insufficient understanding of the intraspecific variation of this trait. We hypothesized that SD in Pinus sylvestris, a widely distributed conifer, varies geographically and that this variation is determined by major climatic variables. By sampling needles from naturally growing trees along a latitudinal range of 32.25°, equivalent to 13.7°C gradient of mean annual temperature (MAT) across Europe, we found that SD decreased from the warmest southern sites to the coldest sites in the north at a rate of 4 stomata per mm2 for each 1°C, with MAT explaining 44% of the variation. Additionally, samples from a provenance trial exhibited a positive relationship between SD and the MAT of the original localities, suggesting that high SD is an adaptation to warm temperature. Our study revealed one of the strongest intraspecific relationships between SD and climate in any woody species, supporting the utility of SD as a temperature, rather than direct CO2 , proxy. In addition, our results predict the response of SD to climate warming.
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Affiliation(s)
- Sławomir Marek
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | | | - Roma Żytkowiak
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | - Anna Jasińska
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | - Marcin Zadworny
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | | | | | - Darius Danusevičius
- Faculty of Forest Science and Ecology, Aleksandras Stulginskis University, Akademija, Kaunas, Lithuania
| | - Jacek Oleksyn
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | - Tomasz P Wyka
- Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
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Abstract
The study is intended for forest farmers who need to make a mathematically sound and objective decision on the choice of technological operations and technical means for forest restoration. Currently, in studies implementing the forest landscapes restoration approach from the point of view of technology and the use of technical devices (FLR technology), there is some discreteness and fragmentation of the issues. There is a need for a comprehensive study of FLR technology using frontier techniques and devices, and the construction of a single technological FLR algorithm. Preliminary analysis indicates a sharp increase in the number of operational sets from nine for the implementation of the classical technological FLR algorithm to 268 in the first approximation when implementing the proposed algorithm. The FLR algorithm construction is based on the algorithm’s theory, and the verification of the similarity degree of operational sets is based on the cluster analysis by Ward and intra-group connections methods. The algorithm decomposition into six conditionally similar clusters will help plan new forest experiments taking into account interdisciplinary interaction, in addition to the modernization of plant propagation protocols for sustainable reforestation quality management. However, some questions remain for the future: which criterion should be used as a universal basis for choosing operational sets? How can the effectiveness of the FLR technology procedure be evaluated and predicted before its practical implementation?
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