Turgor loss in vessel-associated parenchyma cells increases xylem vulnerability to embolism
© The Author(s) 2025. Published by Oxford University Press on behalf of the Society for Experimental Biology.
| Publié dans: | Journal of experimental botany. - 1985. - (2025) vom: 24. Okt. |
|---|---|
| Auteur principal: | |
| Autres auteurs: | , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2025
|
| Accès à la collection: | Journal of experimental botany |
| Sujets: | Journal Article VAC black poplar drought embolism resistance osmotic potential pit membrane plasmolysis vessel-parenchyma pit |
| Résumé: | © The Author(s) 2025. Published by Oxford University Press on behalf of the Society for Experimental Biology. Drought-induced depletion of non-structural carbohydrates has been reported to impact xylem hydraulic vulnerability, which in turn is frequently correlated with water potential at turgor loss point. Considering that non-structural carbohydrate depletion can impair osmoregulation, we hypothesised that vessel-associated parenchyma cells (VAC) that undergo drought-induced turgor loss and plasmolysis could facilitate gas movement and xylem embolism formation. Plasmolysis was induced in wood parenchyma of Populus nigra stems of mature trees and potted plants by radial injection or axial perfusion with a polyethylene glycol solution at low osmotic potential. The effect of polyethylene glycol on embolism resistance was assessed with the gas injection technique followed by classic hydraulic quantification of embolism, as well as with flow-centrifuge measurements. Light and transmission electron microscopy confirmed the occurrence of plasmolysis of VAC in osmotically treated samples, while hydraulic measurements revealed an increase in xylem vulnerability to embolism upon induction of plasmolysis, rising loss of hydraulic conductivity by about 20 to 40%. The results support the hypothesis that the maintenance of cell turgor in VAC is critical for xylem hydraulic integrity under drought. We speculate that plasmolysis of VAC could promote gas movement to functional vessels via vessel-parenchyma pits, increasing the likelihood of embolism propagation |
|---|---|
| Description: | Date Revised 24.10.2025 published: Print-Electronic Citation Status Publisher |
| ISSN: | 1460-2431 |
| DOI: | 10.1093/jxb/eraf470 |