Drought survival in conifer species is related to the time required to cross the stomatal safety margin

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Anja Petek-Petrik - , Czech Academy of Sciences (Author)
  • Peter Petrík - , Karlsruhe Institute of Technology (Author)
  • Laurent J. Lamarque - , Université de Bordeaux, Université du Québec à Trois-Rivières (Author)
  • Hervé Cochard - , Université Clermont Auvergne (Author)
  • Régis Burlett - , Université de Bordeaux (Author)
  • Sylvain Delzon - , Université de Bordeaux (Author)

Abstract

The regulation of water loss and the spread of xylem embolism have mostly been considered separately. The development of an integrated approach taking into account the temporal dynamics and relative contributions of these mechanisms to plant drought responses is urgently needed. Do conifer species native to mesic and xeric environments display different hydraulic strategies and temporal sequences under drought? A dry-down experiment was performed on seedlings of four conifer species differing in embolism resistance, from drought-sensitive to extremely drought-resistant species. A set of traits related to drought survival was measured, including turgor loss point, stomatal closure, minimum leaf conductance, and xylem embolism resistance. All species reached full stomatal closure before the onset of embolism, with all but the most drought-sensitive species presenting large stomatal safety margins, demonstrating that highly drought-resistant species do not keep their stomata open under drought conditions. Plant dry-down time to death was significantly influenced by the xylem embolism threshold, stomatal safety margin, and minimum leaf conductance, and was best explained by the newly introduced stomatal margin retention index (SMRIΨ50) which reflects the time required to cross the stomatal safety margin. The SMRIΨ50 may become a key tool for the characterization of interspecific drought survival variability in trees.

Details

Original languageEnglish
Pages (from-to)6847-6859
Number of pages13
JournalJournal of experimental botany
Volume74
Issue number21
Publication statusPublished - 21 Nov 2023
Peer-reviewedYes
Externally publishedYes

External IDs

ORCID /0000-0002-1092-3031/work/168208043

Keywords

ASJC Scopus subject areas

Keywords

  • Drought tolerance, embolism resistance, residual transpiration, stomatal closure, stomatal safety margin, tree mortality