Download the full-sized PDF
Permanent link (DOI): https://doi.org/10.7939/R3WR6S
This file is in the following communities:
|Renewable Resources, Department of|
This file is in the following collections:
|Journal Articles (Renewable Resources)|
Hydraulic consequences of vessel evolution in angiosperms Open Access
- Author or creator
- Additional contributors
Ecological wood anatomy
Basal angiosperm physiology
- Type of item
- Journal Article (Published)
We tested two hypotheses for how vessel evolution in angiosperms influenced xylem function. First, the transition to vessels decreased resistance to flow-often considered the driving force for their evolution. Second, the transition to vessels compromised safety from cavitation-a constraint emerging from the \"pit area hypothesis\" for vulnerability to cavitation. Data were obtained from branch wood of 17 basal taxa with vessels and two eudicots possessing \"primitive\" perforation plates. Results were compared with previous data from vesselless angiosperms and eudicots with simple perforation plates. Contrary to the first hypothesis, basal taxa did not have significantly lower sapwood-specific resistivity than vesselless angiosperms, despite vessels being wider than tracheids. Eudicot resistivity was ca. 4.5 times lower. On a vessel-area basis, resistivity of \"primitive\" vessels (435 +/- 104 MPa s m(-2)) was lower than angiosperm tracheids (906 +/- 89 MPa s m(-2)) but still greater than eudicot vessels (91 +/- 9 MPa s m(-2)). High resistivity of primitive vessels could be attributed to their being shorter per diameter than eudicots and to high perforation plate resistivity (57% 6 15% of total) in the species with scalariform plates. In support of the second hypothesis, primitive vessels had a cavitation pressure 1.4 MPa more vulnerable than angiosperm tracheids. This \"vulnerability bottleneck\" may have been even more extreme without a shift in vessels to less porous interconduit pit membranes. Vessel evolution was not driven by lower flow resistance, and it may have been limited to wet habitats by cavitation risk. A subtle, context-dependent advantage to primitive vessels is consistent with the distribution of the vesselless condition in the angiosperm tree. The results imply that truly efficient and safe vessels evolved much later than vessels per se, perhaps in concordance with larger radiations among core angiosperms.
- Date created
- License information
- © 2007 University of Chicago Press. This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.
- Citation for previous publication
Sperry, JS; Hacke, UG; Feild, T; Sano, Y; Sikkema, EH. (2007). Hydraulic consequences of vessel evolution in angiosperms. International Journal of Plant Science, 168(8), 1127–1139. DOI: 10.1086/520726.
- Link to related item
- Date Uploaded
- Date Modified
- Audit Status
- Audits have not yet been run on this file.
File format: pdf (PDF/A)
Mime type: application/pdf
File size: 1373043
Last modified: 2015:10:12 11:50:28-06:00
Original checksum: 4a0cce104347f084a821e700760e41eb
Well formed: true
File title: IJPS30462_proof 1127..1139
Page count: 13