Drought‐induced xylem embolism is a primary cause of plant mortality. Although We quantified the vulnerability to drought‐induced embolism, pressure–volume curves, Compared with other major vascular plant clades, cycads exhibited similar embolism resistance to angiosperms and pteridophytes but were more vulnerable to embolism than noncycad gymnosperms. All 20 cycads had both tracheids and vessels, the proportions of which were unrelated to embolism resistance. Only vessel pit membrane fraction was positively correlated to embolism resistance, contrary to angiosperms. Water potential at turgor loss was significantly correlated to embolism resistance among cycads. Our results show that cycads exhibit low resistance to xylem embolism and that xylem anatomical traits – particularly vessels – may influence embolism resistance together with tracheids. This study highlights the importance of understanding the mechanisms of drought resistance in evolutionarily unique and threatened lineages like the cycads.
This content will become publicly available on July 1, 2025
- Award ID(s):
- 2243971
- PAR ID:
- 10511969
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- New phytologist
- ISSN:
- 1469-8137
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Drought events may increase the likelihood that the plant water transport system becomes interrupted by embolism. Yet our knowledge about the temporal frequency of xylem embolism in the field is frequently lacking, as it requires detailed, long‐term measurements.
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T PMdata show that leaf xylem is generally no more vulnerable than stem xylem.
