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Kuo WH, Liu SH, Chang CC, Hsieh CL, Li YH, Ito T, Won H, Kokubugata G, Chung KF. Plastome phylogenomics of Allaeanthus, Broussonetia and Malaisia (Dorstenieae, Moraceae) and the origin of B. × kazinoki. JOURNAL OF PLANT RESEARCH 2022; 135:203-220. [PMID: 35080694 DOI: 10.1007/s10265-022-01369-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Species of Broussonetia have been essential in the development of papermaking technology. In Japan and Korea, a hybrid between B. monoica and B. papyrifera (= B. × kazinoki) known as kōzo and daknamu is still the major source of raw materials for making traditional paper washi and hanji, respectively. Despite their cultural and practical significance, however, the origin and taxonomy of kōzo and daknamu remain controversial. Additionally, the long-held generic concept of Broussonetia s.l., which included Sect. Allaeanthus and Sect. Broussonetia, was challenged as phylogenetic analyses showed Malaisia is sister to the latter section. To re-examine the taxonomic proposition that recognizes Allaeanthus, Broussonetia, and Malaisia (i.e., Broussonetia alliance), plastome and nuclear ribosomal DNA (nrDNA) sequences of six species of the alliance were assembled. Characterized by the canonical quadripartite structure, genome alignments and contents of the six plastomes (160,121-162,594 bp) are highly conserved, except for the pseudogenization and/or loss of the rpl22 gene. Relationships of the Broussonetia alliance are identical between plastome and nrDNA trees, supporting the maintenance of Malaisia and the resurrection of Allaeanthus. The phylogenomic relationships also indicate that the monoecy in B. monoica is a derived state, possibly resulting from hybridization between the dioecious B. kaempferi (♀) and B. papyrifera (♂). Based on the hypervariable ndhF-rpl32 intergenic spacer selected by sliding window analysis, phylogeographic analysis indicates that B. monoica is the sole maternal parent of B. × kazinoki and that daknamu carries multiple haplotypes, while only one haplotype was detected in kōzo. Because hybridizations between B. monoica and B. papyrifera are unidirectional and have occurred rarely in nature, our data suggest that daknamu might have originated via deliberate hybrid breeding selected for making hanji in Korea. On the contrary, kōzo appears to have a single origin and the possibility of a Korean origin cannot be ruled out.
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Affiliation(s)
- Wen-Hsi Kuo
- Research Museum and Herbarium (HAST), Biodiversity Research Center, Academia Sinica, Taipei, 115201, Taiwan
- Department of Biology, Washington University, St. Louis, MO, USA
| | - Shih-Hui Liu
- Department of Biological Sciences, National Sun Yat- sen University, Kaohsiung, Taiwan
| | - Chiung-Chih Chang
- Research Museum and Herbarium (HAST), Biodiversity Research Center, Academia Sinica, Taipei, 115201, Taiwan
| | - Chia-Lun Hsieh
- Research Museum and Herbarium (HAST), Biodiversity Research Center, Academia Sinica, Taipei, 115201, Taiwan
| | - Yi-Hsuan Li
- Research Museum and Herbarium (HAST), Biodiversity Research Center, Academia Sinica, Taipei, 115201, Taiwan
| | - Takuro Ito
- The Center for Academic Resources and Archives/Botanical Gardens, Tohoku University, Sendai, Miyagi, Japan
| | - Hyosig Won
- Department of Biological Science and Institute of Natural Sciences, Daegu University, Gyungsan, Gyungbuk, South Korea
| | - Goro Kokubugata
- Department of Botany, National Museum of Nature and Science, Tsukuba, Ibaraki, Japan
| | - Kuo-Fang Chung
- Research Museum and Herbarium (HAST), Biodiversity Research Center, Academia Sinica, Taipei, 115201, Taiwan.
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Genome Size, Cytotype Diversity and Reproductive Mode Variation of Cotoneaster integerrimus (Rosaceae) from the Balkans. PLANTS 2021; 10:plants10122798. [PMID: 34961270 PMCID: PMC8708406 DOI: 10.3390/plants10122798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 12/28/2022]
Abstract
Cotoneaster integerrimus represents a multiploid and facultative apomictic system of widely distributed mountain populations. We used flow cytometry to determine genome size, ploidy level, and reproduction mode variation of the Balkan populations, supplemented by analysis of nuclear microsatellites in order to address: (i) geographic distribution and variation of cytotypes among the populations; (ii) variation of reproduction mode and the frequency of sexuality; (iii) pathways of endosperm formation among the sampled polyploids and their endosperm balance requirements; (iv) genotypic diversity and geographic distribution of clonal lineages of polyploids. The prevalence of apomictic tetraploid cytotype followed by sexual diploids and extremely rare triploids was demonstrated. This prevalence of tetraploids affected the populations’ structure composed from clonal genotypes with varying proportions. The co-occurrence of diploids and tetraploids generated higher cytotype, reproductive mode, and genotypic diversity, but mixed-ploidy sites were extremely rare. The endosperm imbalance facilitates the development and the occurrence of intermediate triploids in mixed-ploidy populations, but also different tetraploid lineages elsewhere with unbalanced endosperm. All these results showed that the South European populations of C. integerrimus have higher levels of cytotype and reproductive diversity compared to the Central European ones. Therefore, the South European populations can be considered as a potential reservoir of regional and global diversity for this species.
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Ďurkovič J, Husárová H, Javoříková L, Čaňová I, Šuleková M, Kardošová M, Lukáčik I, Mamoňová M, Lagaňa R. Physiological, vascular and nanomechanical assessment of hybrid poplar leaf traits in micropropagated plants and plants propagated from root cuttings: A contribution to breeding programs. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 118:449-459. [PMID: 28743038 DOI: 10.1016/j.plaphy.2017.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 07/10/2017] [Accepted: 07/13/2017] [Indexed: 05/03/2023]
Abstract
Micropropagated plants experience significant stress from rapid water loss when they are transferred from an in vitro culture to either greenhouse or field conditions. This is caused both by inefficient stomatal control of transpiration and the change to a higher light intensity and lower humidity. Understanding the physiological, vascular and biomechanical processes that allow micropropagated plants to modify their phenotype in response to environmental conditions can help to improve both field performance and plant survival. To identify changes between the hybrid poplar [Populus tremula × (Populus × canescens)] plants propagated from in vitro tissue culture and those from root cuttings, we assessed leaf performance for any differences in leaf growth, photosynthetic and vascular traits, and also nanomechanical properties of the tracheary element cell walls. The micropropagated plants showed significantly higher values for leaf area, leaf length, leaf width and leaf dry mass. The greater leaf area and leaf size dimensions resulted from the higher transpiration rate recorded for this stock type. Also, the micropropagated plants reached higher values for chlorophyll a fluorescence parameters and for the nanomechanical dissipation energy of tracheary element cell walls which may indicate a higher damping capacity within the primary xylem tissue under abiotic stress conditions. The performance of the plants propagated from root cuttings was superior for instantaneous water-use efficiency which signifies a higher acclimation capacity to stressful conditions during a severe drought particularly for this stock type. Similarities were found among the majority of the examined leaf traits for both vegetative plant origins including leaf mass per area, stomatal conductance, net photosynthetic rate, hydraulic axial conductivity, indicators of leaf midrib vascular architecture, as well as for the majority of cell wall nanomechanical traits. This research revealed that there were no drawbacks in the leaf physiological performance which could be attributed to the micropropagated plants of fast growing hybrid poplar.
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Affiliation(s)
- Jaroslav Ďurkovič
- Department of Phytology, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic.
| | - Hana Husárová
- Department of Phytology, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Lucia Javoříková
- Department of Phytology, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Ingrid Čaňová
- Department of Phytology, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Miriama Šuleková
- Department of Integrated Forest and Landscape Protection, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Monika Kardošová
- Department of Integrated Forest and Landscape Protection, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Ivan Lukáčik
- Department of Silviculture, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Miroslava Mamoňová
- Department of Wood Science, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
| | - Rastislav Lagaňa
- Department of Wood Science, Technical University, T.G. Masaryka 24, 960 53 Zvolen, Slovak Republic
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Plichta R, Urban J, Gebauer R, Dvořák M, Ďurkovič J. Long-term impact of Ophiostoma novo-ulmi on leaf traits and transpiration of branches in the Dutch elm hybrid 'Dodoens'. TREE PHYSIOLOGY 2016; 36:335-44. [PMID: 26843210 PMCID: PMC4885949 DOI: 10.1093/treephys/tpv144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 12/21/2015] [Indexed: 05/07/2023]
Abstract
To better understand the long-term impact of Ophiostoma novo-ulmi Brasier on leaf physiology in 'Dodoens', a Dutch elm disease-tolerant hybrid, measurements of leaf area, leaf dry mass, petiole anatomy, petiole hydraulic conductivity, leaf and branch water potential, and branch sap flow were performed 3 years following an initial artificial inoculation. Although fungal hyphae were detected in fully expanded leaves, neither anatomical nor morphological traits were affected, indicating that there was no impact from the fungal hyphae on the leaves during leaf expansion. In contrast, however, infected trees showed both a lower transpiration rate of branches and a lower sap flow density. The long-term persistence of fungal hyphae inside vessels decreased the xylem hydraulic conductivity, but stomatal regulation of transpiration appeared to be unaffected as the leaf water potential in both infected and non-infected trees was similarly driven by the transpirational demands. Regardless of the fungal infection, leaves with a higher leaf mass per area ratio tended to have a higher leaf area-specific conductivity. Smaller leaves had an increased number of conduits with smaller diameters and thicker cell walls. Such a pattern could increase tolerance towards hydraulic dysfunction. Measurements of water potential and theoretical xylem conductivity revealed that petiole anatomy could predict the maximal transpiration rate. Three years following fungal inoculation, phenotypic expressions for the majority of the examined traits revealed a constitutive nature for their possible role in Dutch elm disease tolerance of 'Dodoens' trees.
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Affiliation(s)
- Roman Plichta
- Department of Forest Botany, Dendrology and Geobiocoenology, Mendel University in Brno, Zemědělská 3, 61300 Brno, Czech Republic
| | - Josef Urban
- Department of Forest Botany, Dendrology and Geobiocoenology, Mendel University in Brno, Zemědělská 3, 61300 Brno, Czech Republic
| | - Roman Gebauer
- Department of Forest Botany, Dendrology and Geobiocoenology, Mendel University in Brno, Zemědělská 3, 61300 Brno, Czech Republic
| | - Miloň Dvořák
- Department of Forest Protection and Wildlife Management, Mendel University in Brno, Zemědělská 3, 61300 Brno, Czech Republic
| | - Jaroslav Ďurkovič
- Department of Phytology, Technical University in Zvolen, T. G. Masaryka 24, 960 53 Zvolen, Slovak Republic
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Hajrudinović A, Siljak-Yakovlev S, Brown SC, Pustahija F, Bourge M, Ballian D, Bogunić F. When sexual meets apomict: genome size, ploidy level and reproductive mode variation of Sorbus aria s.l. and S. austriaca (Rosaceae) in Bosnia and Herzegovina. ANNALS OF BOTANY 2015; 116:301-12. [PMID: 26113635 PMCID: PMC4512196 DOI: 10.1093/aob/mcv093] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/23/2015] [Accepted: 05/07/2015] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS Allopolyploidy and intraspecific heteroploid crosses are associated, in certain groups, with changes in the mating system. The genus Sorbus represents an appropriate model to study the relationships between ploidy and reproductive mode variations. Diploid S. aria and tetraploid apomictic S. austriaca were screened for ploidy and mating system variations within pure and sympatric populations in order to gain insights into their putative causalities. METHODS Flow cytometry was used to assess genome size and ploidy level among 380 S. aria s.l. and S. austriaca individuals from Bosnia and Herzegovina, with 303 single-seed flow cytometric seed screenings being performed to identify their mating system. Pollen viability and seed set were also determined. KEY RESULTS Flow cytometry confirmed the presence of di-, tri- and tetraploid cytotype mixtures in mixed-ploidy populations of S. aria and S. austriaca. No ploidy variation was detected in single-species populations. Diploid S. aria mother plants always produced sexually originated seeds, whereas tetraploid S. austriaca as well as triploid S. aria were obligate apomicts. Tetraploid S. aria preserved sexuality in a low portion of plants. A tendency towards a balanced 2m : 1p parental genome contribution to the endosperm was shared by diploids and tetraploids, regardless of their sexual or asexual origin. In contrast, most triploids apparently tolerated endosperm imbalance. CONCLUSIONS Coexistence of apomictic tetraploids and sexual diploids drives the production of novel polyploid cytotypes with predominantly apomictic reproductive modes. The data suggest that processes governing cytotype diversity and mating system variation in Sorbus from Bosnia and Herzegovina are probably parallel to those in other diversity hotspots of this genus. The results represent a solid contribution to knowledge of the reproduction of Sorbus and will inform future investigations of the molecular and genetic mechanisms involved in triggering and regulating cytotype diversity and alteration of reproductive modes.
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Affiliation(s)
- Alma Hajrudinović
- Faculty of Forestry, University of Sarajevo, Zagrebačka 20, 71000 Sarajevo, Bosnia and Herzegovina
| | - Sonja Siljak-Yakovlev
- CNRS, Université Paris-Sud, AgroParisTech, UMR 8079, Ecologie, Systématique, Evolution, Bât. 360, 91450 Orsay, France and
| | - Spencer C Brown
- Pôle de Biologie Cellulaire, Imagif, Centre de Recherche de Gif (FRC3115), CNRS, Saclay Plant Sciences, 91198, Gif-sur-Yvette Cedex, France
| | - Fatima Pustahija
- Faculty of Forestry, University of Sarajevo, Zagrebačka 20, 71000 Sarajevo, Bosnia and Herzegovina
| | - Mickael Bourge
- Pôle de Biologie Cellulaire, Imagif, Centre de Recherche de Gif (FRC3115), CNRS, Saclay Plant Sciences, 91198, Gif-sur-Yvette Cedex, France
| | - Dalibor Ballian
- Faculty of Forestry, University of Sarajevo, Zagrebačka 20, 71000 Sarajevo, Bosnia and Herzegovina
| | - Faruk Bogunić
- Faculty of Forestry, University of Sarajevo, Zagrebačka 20, 71000 Sarajevo, Bosnia and Herzegovina,
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Ďurkovič J, Čaňová I, Kardošová M, Kurjak D. Seasonal patterns of leaf photosynthetic and secondary xylem vascular traits in current-year stems of three Sorbus species with contrasting growth habits. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16:908-916. [PMID: 24456305 DOI: 10.1111/plb.12150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 12/17/2013] [Indexed: 06/03/2023]
Abstract
Seasonal effects of environmental variables on photosynthetic activity and secondary xylem formation provide data to demonstrate how environmental factors together with leaf ageing during the season control tree growth. In this study, we assessed physiological responses in photosynthetic behaviour to seasonal climate changes, and also identified seasonal differences in vascular traits within differentiating secondary xylem tissue from three diploid species of the taxonomically complex genus Sorbus. From sampling day 150, a clear physiological segregation of S. chamaemespilus from S. torminalis and S. aria was evident. The shrubby species S. chamaemespilus could be distinguished by a higher photosynthetic capacity between days 150 and 206. This was reflected in its associations with net CO2 assimilation rate (PN), maximum photochemical efficiency of PSII (F(v)/F(m)), variable-to-initial fluorescence ratio (F(v)/F(0)), potential electron acceptor capacity ('area') in multivariate space, and also its associations with log-transformed vessel area and log-transformed relative conductivity between days 239 and 268. The maximum segregation and differentiation among the examined Sorbus species was on sampling day 206. The largest differences between S. torminalis and S. aria were found on day 115, when the latter species clearly showed closer associations with high values of vessel density and transpiration (E). Sampling day clusters were arranged along an arch-like gradient that reflected the positioning of the entire growing season in multivariate space. This arch-like pattern was most apparent in the case of S. chamaemespilus, but was also observed in S. torminalis and S. aria.
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Affiliation(s)
- J Ďurkovič
- Department of Phytology, Technical University, Zvolen, Slovakia
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Hodač L, Scheben AP, Hojsgaard D, Paun O, Hörandl E. ITS polymorphisms shed light on hybrid evolution in apomictic plants: a case study on the Ranunculus auricomus complex. PLoS One 2014; 9:e103003. [PMID: 25062066 PMCID: PMC4111349 DOI: 10.1371/journal.pone.0103003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 06/23/2014] [Indexed: 11/18/2022] Open
Abstract
The reconstruction of reticulate evolutionary histories in plants is still a major methodological challenge. Sequences of the ITS nrDNA are a popular marker to analyze hybrid relationships, but variation of this multicopy spacer region is affected by concerted evolution, high intraindividual polymorphism, and shifts in mode of reproduction. The relevance of changes in secondary structure is still under dispute. We aim to shed light on the extent of polymorphism within and between sexual species and their putative natural as well as synthetic hybrid derivatives in the Ranunculus auricomus complex to test morphology-based hypotheses of hybrid origin and parentage of taxa. We employed direct sequencing of ITS nrDNA from 68 individuals representing three sexuals, their synthetic hybrids and one sympatric natural apomict, as well as cloning of ITS copies in four representative individuals, RNA secondary structure analysis, and landmark geometric morphometric analysis on leaves. Phylogenetic network analyses indicate additivity of parental ITS variants in both synthetic and natural hybrids. The triploid synthetic hybrids are genetically much closer to their maternal progenitors, probably due to ploidy dosage effects, although exhibiting a paternal-like leaf morphology. The natural hybrids are genetically and morphologically closer to the putative paternal progenitor species. Secondary structures of ITS1-5.8S-ITS2 were rather conserved in all taxa. The observed similarities in ITS polymorphisms suggest that the natural apomict R. variabilis is an ancient hybrid of the diploid sexual species R. notabilis and the sexual species R. cassubicifolius. The additivity pattern shared by R. variabilis and the synthetic hybrids supports an evolutionary and biogeographical scenario that R. variabilis originated from ancient hybridization. Concerted evolution of ITS copies in R. variabilis is incomplete, probably due to a shift to asexual reproduction. Under the condition of comprehensive inter- and intraspecific sampling, ITS polymorphisms are powerful for elucidating reticulate evolutionary histories.
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Affiliation(s)
- Ladislav Hodač
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
| | - Armin Patrick Scheben
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
| | - Diego Hojsgaard
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
| | - Ovidiu Paun
- Division of Systematic and Evolutionary Botany, University of Vienna, Vienna, Austria
| | - Elvira Hörandl
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
- * E-mail:
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Ďurkovič J, Kardošová M, Lagaňa R. Imaging and Measurement of Nanomechanical Properties within Primary Xylem Cell Walls of Broadleaves. Bio Protoc 2014. [DOI: 10.21769/bioprotoc.1360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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Durkovic J, Canová I, Lagana R, Kucerová V, Moravcík M, Priwitzer T, Urban J, Dvorák M, Krajnáková J. Leaf trait dissimilarities between Dutch elm hybrids with a contrasting tolerance to Dutch elm disease. ANNALS OF BOTANY 2013; 111:215-27. [PMID: 23264236 PMCID: PMC3555532 DOI: 10.1093/aob/mcs274] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 11/13/2012] [Indexed: 05/15/2023]
Abstract
BACKGROUND AND AIMS Previous studies have shown that Ophiostoma novo-ulmi, the causative agent of Dutch elm disease (DED), is able to colonize remote areas in infected plants of Ulmus such as the leaf midrib and secondary veins. The objective of this study was to compare the performances in leaf traits between two Dutch elm hybrids 'Groeneveld' and 'Dodoens' which possess a contrasting tolerance to DED. Trait linkages were also tested with leaf mass per area (LMA) and with the reduced Young's modulus of elasticity (MOE) as a result of structural, developmental or functional linkages. METHODS Measurements and comparisons were made of leaf growth traits, primary xylem density components, gas exchange variables and chlorophyll a fluorescence yields between mature plants of 'Groeneveld' and 'Dodoens' grown under field conditions. A recently developed atomic force microscopy technique, PeakForce quantitative nanomechanical mapping, was used to reveal nanomechanical properties of the cell walls of tracheary elements such as MOE, adhesion and dissipation. KEY RESULTS 'Dodoens' had significantly higher values for LMA, leaf tissue thickness variables, tracheary element lumen area (A), relative hydraulic conductivity (RC), gas exchange variables and chlorophyll a fluorescence yields. 'Groeneveld' had stiffer cell walls of tracheary elements, and higher values for water-use efficiency and leaf water potential. Leaves with a large carbon and nutrient investment in LMA tended to have a greater leaf thickness and a higher net photosynthetic rate, but LMA was independent of RC. Significant linkages were also found between the MOE and some vascular traits such as RC, A and the number of tracheary elements per unit area. CONCLUSIONS Strong dissimilarities in leaf trait performances were observed between the examined Dutch elm hybrids. Both hybrids were clearly separated from each other in the multivariate leaf trait space. Leaf growth, vascular and gas exchange traits in the infected plants of 'Dodoens' were unaffected by the DED fungus. 'Dodoens' proved to be a valuable elm germplasm for further breeding strategies.
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