Abstract
C2 photosynthesis is characterised using recapturing photorespiratory CO2 by RuBisCo in Kranz-like cells and is therefore physiologically intermediate between C3 and C4 photosynthesis. C2 can be interpreted as an evolutionary precursor of C4 and/or as the result of hybridisation between a C3 and C4 lineage. We compared the expression of photosynthetic traits among populations of the Salsola divaricata agg. (C2) from humid subtropical to arid habitats on the coasts of the Canary Islands and Morocco and subjected them to salt and drought treatments. We screened for enhanced C4-like expression of traits related to habitat or treatment. We estimated species trees with a transcriptome dataset of Salsoleae and explored patterns of gene tree discordance. With phylogenetic networks and hybridisation analyses we tested for the hybrid origin of the Salsola divaricata agg. We observed distinct independent variation of photosynthetic traits within and among populations and no clear evidence for selection towards C4-like trait expression in more stressful habitats or treatments. We found reticulation and gene tree incongruence in Salsoleae supporting a putative hybrid origin of the Salsola divaricata agg. C2 photosynthesis in the Salsola divaricata agg. combines traits inherited from its C3 and C4 parental lineages and seems evolutionarily stable, possibly well adapted to a wide climatic amplitude.
Original language | English (US) |
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Pages (from-to) | 1876-1890 |
Number of pages | 15 |
Journal | New Phytologist |
Volume | 234 |
Issue number | 5 |
DOIs | |
State | Published - Jun 2022 |
Bibliographical note
Funding Information:Funding for this project came from the German Science Foundation (Deutsche Forschungsgemeinschaft e.V.; DFG grant no. KA1816/9-1) and the University of Minnesota Twin Cities, St. Paul, MN, USA. We thank the collectors of seeds of Salsola divaricata agg. for their great help in starting this project, in particular R. Barone, V. Boehlke, H. Freitag, J. Gil González, F. Hernández, M. Olangua Corral, S. Scholz and E. Voznesenskaya. We are grateful to C. Wild for cultivating and maintaining the plants for this project. For conducting a part of the carbon isotope measurements, we thank M. Maus (Geology Department, University of Mainz, Germany). The Minnesota Supercomputing Institute provided access to computational resources. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Funding Information:
Funding for this project came from the German Science Foundation (Deutsche Forschungsgemeinschaft e.V.; DFG grant no. KA1816/9‐1) and the University of Minnesota Twin Cities, St. Paul, MN, USA. We thank the collectors of seeds of agg. for their great help in starting this project, in particular R. Barone, V. Boehlke, H. Freitag, J. Gil González, F. Hernández, M. Olangua Corral, S. Scholz and E. Voznesenskaya. We are grateful to C. Wild for cultivating and maintaining the plants for this project. For conducting a part of the carbon isotope measurements, we thank M. Maus (Geology Department, University of Mainz, Germany). The Minnesota Supercomputing Institute provided access to computational resources. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Salsola divaricata
Publisher Copyright:
© 2022 The Authors. New Phytologist © 2022 New Phytologist Foundation.
Keywords
- Amaranthaceae
- C photosynthesis
- CO compensation point
- Salsola divaricata agg
- carbon isotope values
- hybridisation events
- phosphoenolpyruvate carboxylase
- phylogenomics
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't