Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 7-Day Trial for You or Your Team.

Learn More →

Xylem dysfunction in Quercus: vessel sizes, tyloses, cavitation and seasonal changes in embolism

Xylem dysfunction in Quercus: vessel sizes, tyloses, cavitation and seasonal changes in embolism Abstract The seasonal progression of xylem dysfunction from tyloses and embolism induced both by cavitation and frost was studied in Quercus rubra L. and Quercus alba L. branches. Vessel lengths and diameters were measured in current-year rings of branches of various ages. Vessels in current-year shoots are about the same size as those in many diffuse porous trees, but vessels in older branches are two to six times larger in diameter and typically more than 10 times longer. Large Quercus vessels were more vulnerable to cavitation than small vessels. The small vessels in current-year shoots were more vulnerable to cavitation than vessels of comparable size in diffuse porous species. Earlywood vessels are completely blocked by tyloses within a year of their formation. Tylose growth starts in winter, but the vessels are not fully blocked until the next summer. Many latewood vessels, by contrast, remain free of complete blockage for several years. In Q. rubra, loss of hydraulic conductivity in current-year shoots due to cavitation reaches 20% by August and > 90% after the first hard frost. Both laboratory and field observations confirm that the role of frost in causing loss of hydraulic conduction by embolism is much more dramatic in Quercus than in conifers and diffuse porous hardwoods. This content is only available as a PDF. © 1990 Heron Publishing—Victoria Canada http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Tree Physiology Oxford University Press

Xylem dysfunction in Quercus: vessel sizes, tyloses, cavitation and seasonal changes in embolism

Cochard,, Hervé; Tyree, Melvin, T.
Tree Physiology , Volume 6 (4) – Dec 1, 1990
Download PDF
16 pages

Loading next page...
 
/lp/oxford-university-press/xylem-dysfunction-in-quercus-vessel-sizes-tyloses-cavitation-and-gRzAAx0XIT

References (27)

Publisher
Oxford University Press
Copyright
© 1990 Heron Publishing—Victoria Canada
ISSN
0829-318X
eISSN
1758-4469
DOI
10.1093/treephys/6.4.393
Publisher site
See Article on Publisher Site

Abstract

Abstract The seasonal progression of xylem dysfunction from tyloses and embolism induced both by cavitation and frost was studied in Quercus rubra L. and Quercus alba L. branches. Vessel lengths and diameters were measured in current-year rings of branches of various ages. Vessels in current-year shoots are about the same size as those in many diffuse porous trees, but vessels in older branches are two to six times larger in diameter and typically more than 10 times longer. Large Quercus vessels were more vulnerable to cavitation than small vessels. The small vessels in current-year shoots were more vulnerable to cavitation than vessels of comparable size in diffuse porous species. Earlywood vessels are completely blocked by tyloses within a year of their formation. Tylose growth starts in winter, but the vessels are not fully blocked until the next summer. Many latewood vessels, by contrast, remain free of complete blockage for several years. In Q. rubra, loss of hydraulic conductivity in current-year shoots due to cavitation reaches 20% by August and > 90% after the first hard frost. Both laboratory and field observations confirm that the role of frost in causing loss of hydraulic conduction by embolism is much more dramatic in Quercus than in conifers and diffuse porous hardwoods. This content is only available as a PDF. © 1990 Heron Publishing—Victoria Canada

Journal

Tree Physiology – Oxford University Press

Published: Dec 1, 1990

There are no references for this article.